The Flowering of Monte: Going ‘Viral’ During a Pandemic

 

When will it actually flower?  Once people got passed the, ‘What is ‘that’ question?’, this is what they wanted to know.  When would it actually flower? by which they meant the individual petalous flowers open.   More than a few times I responded snarkily…it’s flowering right now!  Agave are among a wide ranging group of plants whose flowering includes a relatively large inflorescence, a supporting structure, which can rival the rest of the plant in terms of size.  An Agave montana flowering here is foreign to our experience.  The idea that such a large structure  could arise so quickly, is to most people’s minds, strange, if not surreal…but for experienced gardens, who observe and strive to understand, there are links and connections, shared purpose and processes with all flowers.  Gardeners and botanists, horticulturists and evolutionary scientists, they see the wonder in it all.  When does flowering begin?  When a plant commits to its purpose.  Flowering should not be taken for granted.  It does not occur to meet our aesthetic need.  It is also much more than a simple result of a plant’s life.  It is a fulfillment of one well and fully lived, projecting oneself into the future.  Flowering and the production of one’s seed is a commitment to a future that will go on beyond oneself…and it begins from where every plant begins.

It is not a ‘giant asparagus’!  The ‘spike’ you see growing upwards is the ‘peduncle’, the main flowering stem which carries and supports the individual flowers, the penultimate act of an Agave. As it nears its maximum height ‘branches’ will form near the top, forming and extending out from beneath the ‘bracts’, the tightly adpressed leaves, on which will form the yellow flowers. It will form a panicle, a ‘candelabra’ like structure. The vast majority of Agave are monocarpic, yes, there are always exceptions in nature, meaning they only flower once, producing seed and then die. ‘Monte’ is about 23 years old, grown from seed. Many Agave produce ‘offsets’ or ‘pups’ that can be grown on into mature plants, a slightly shorter process than when beginning from seed.  A. montana was only being grown from seed then.  Today it can be produced in a commercial ‘lab’ via tissue culture, TC, under sterile conditions, a method commonly used today to ‘quickly’ produce commercial numbers of plants, when other methods are too slow or not possible.  For a plant that produces seed only after many years of growth it may not be readily available to a grower or its progeny too variable.  TC produces genetically identical ‘clones’.  Seed will always be important to maintain genetic diversity within a species improving its chances of maintaining a population’s overall health, but TC can supply an ‘industry’.  I bought this as a gallon plant about 19 years ago.

When most people think of Agave, if they think anything at all about them, they think of them as desert denizens. Not this one! This is a mountain species from Mexico’s eastern Sierra Madre, where it is found between 6,000’ and 10,000’…..I’ve been told that this might be the first one to flower in the NW. Its native range experiences a temperate climate and receives its heaviest rains late summer-early fall during the hurricane season common to the Gulf Coast of Mexico. It can experience freezing temperatures and even some snow there in open Oak-Pine forest. This species is relatively new to the nursery trade and was only formally described in 1996, 24 years ago. Because of its relatively recent ‘discovery’ and propagation there have been few to bloom to date in the US.

Agave montana, typically begin their flowering process in Fall, then ‘stop’ for a period during winter, finishing in the following Spring/Summer. Most Agave are tropical/sub-tropical plants from deserts and are grown here in pots. There are 200+ species, 3/4 of which are endemic to Mexico, found only there, none are native outside the Americas though they have become common in landscapes around the world from Hawai’i to the Mediterranean, South Africa to Australia and the warmer parts of Asia. Twenty-two species are native to the US, from California into Nevada, Utah, Arizona, New Mexico and Texas. Three are native to Florida.

Portland and the Maritime Pacific Northwest provide challenges to growing any Agave species and hybrid. For many of the tropical species the cold alone can be a death sentence.  Here we have dry summers and wet cool/cold winters…this is not what most Agave need and can lead to rot and/or fungal foliar diseases that can disfigure or kill most Agave species. Species choice and siting considerations are extremely important when growing them under such marginal conditions. They generally require full sun and excellent soil drainage, though some, native to the tropical/low desert benefit from a little shade, shade not necessarily needed when grown here with our less intense sun. Good air circulation helps foliage dry in winter. Sloping sites help with soil drainage. Tilting the plant when planting is helpful as it helps the crown stay dry as the rosette structure tends to ‘focus’ the water toward its roots. Some Agave gardeners here will plant with the rosette somewhat above the soil level on a mound of gravel with their roots in native soil. Agaves, contrary to what many might expect, will do better with some summer water whether in pots or planted out.  In their home range summer is when they receive rainfall though it may be little.  This is when they grow.

[Sept. 12-14  The estimated beginning of flowering, 
I have logged the apparent fall and spring ‘rise’ of the sun over its flowering for comparative purposes, curious about its role in ‘signaling’ the stages of flowering.  On this date, in Portland, OR, its elevation was 48º above the horizon at solar noon, day length 12hrs 39mins; in Monterrey, MX, relatively close to its natural range, the sun reaches an elevation 20º higher in the sky – 68º, at this date with a day length of 12hrs 23mins.  The intensity of the sun in its home range is considerably higher though at this stage day length is fairly close.  Was that a factor?   Day length at more northern latitudes can vary across a much wider range than those to the south.  I don’t have the statistical ability to determine what role solar data may have in flowering and with only one plant by which to judge, I’m not sure that it would be very relevant.  For information on day length and sun elevation for locations around the world go to this link.]

Taken Sept. 29 this closeup shows the different pattern as the primary peduncle begins to shoot up with its pink/red coloring, the congested pattern of thinner, narrower, bracts crowding around it and the closely gathered, less substantial leaves.


[Sept. 29, 2019  Height to tip of growing peduncle, 60″.]

•My Agave is flowering.  We first noticed Monte beginning to flower at the end of last September. The leaves had begun to narrow and thin, crowding, uncharacteristically, in the center. Normally, during its many juvenile years, new growth emerges from the center of the basal rosette from a tightly bound, vertical, narrow ‘cone’ of leaves, at the center, very substantial, almost ‘solid’, unfolding and extending one at a time in the same radial pattern that defines everything about this plant. As leaves develop they begin to separate from the ‘cone’ expanding to their full size, ‘imprinted’ with the patterns of the leaves that sandwiched them in the cone. As flowering begins, this structure is replaced by a loose bundle of narrow and thinner leaves. From within this rises the peduncle a distinctive and thickened ‘shaft’ on which form all of the bracts, the modified leaves, to come.  All of an Agave’s top growth arises from the meristem tissue at the base of this ‘cone’.  The rising flowering stem, the primary peduncle, grows upward from cells produced by the same meristem ‘through’ this ‘cone’.  In late September it emerged just below the upper tips of the loosely gathered leaves at the center. The peduncle then added 5 1/2’ more by the end of October, rising at its full width, an average of 2”-3″ per day. Think of this stage of its growth as similar to a tall building rising up, it does not shoot up thin and add diameter later, but rises skyward at full size.

[Oct 28, 2020  The primary peduncle reached 122″, 10′ 2″, the height from which the first branch, or secondary peduncle, would much latter emerge, to form the first tier of the ‘crown’ of the panicle structure.}

• Flowering is mostly powered by the plant’s starchy ‘heart’ or piña, although the basal growth of the leaves probably continue to photosynthesize.  This phase is distinctly different than growth during its long formative stage.  Agave all utilize CAM, Crassulacean Acid Metabolism, which is a conservative photosynthetic process, very efficient regarding its use of water, it is also the slowest of the three recognized metabolic paths. It reduces its losses by separating some of its processes in time, delaying those steps not directly driven by sunlight until night time hours. Night is when their leaves open their stomata to take in CO2 .  Because it’s also cooler at night, there is less water loss out the stomata.  The vast majority of plants follow what botanists call the C3 pathway utilizing a 3 carbon acid during their photosynthetic process.  C3 is the oldest form of photosynthesis in plants developed more than a billion years ago in a very different world.  Water was not a significant limiting factor then and so this pathway is relatively wasteful in its use.  An earlier form of photosynthesis began in algae and bacteria that were always suspended in water.  The chemical ‘work’ the C3 process accomplishes, its metabolites created, can be subject to reversal as its processes are rather ‘open’ and can be readily reversed in the presence of Oxygen in the wrong ‘stages’, through oxidation.  CAM evolved in response to both higher temperature and aridity. (Agave are relatively recent arrivals to the plant world thought to have first evolved some 12-26 million years ago, concurrent with the desertification of North America.)  The several Ice Ages that occurred in the last million would have forced Agave south, the retreating ice slowly drawing them back north.  The other path, C4, not the explosive, is intermediate, utilizing a four carbon acid in the process, while physically separating the stages of photosynthesis within the leaf and thereby reducing losses.  C4 is a relatively rare process and is most commonly found in drought tolerant grasses again developing with rising aridity.  Agave sacrifice the speed of C3 to reduce water loss and to conserve their valuable metabolites by effectively separating the process into two stages.  As a result of this Agave grow slow. 

As one result of this Agave have evolved an ingenious strategy to flower and reproduce.  For twenty plus years Monte’s basal rosette grew expanding its photosynthetic capacity and storing energy in the form of starches, which are complex long chains of sugar molecules, in its dense, potato like heart or piña. Once it ‘recognized’ that it had surpassed its energy requirement for successful reproduction, and our September rains came, a pattern it recognizes from its native region, Monte flipped a hormonal switch and began to utilize its rosette and heart as a ‘chemical battery’, water supply and ‘storehouse’ of raw materials with which it could build its massive inflorescence…quickly.  There is no way that an Agave could produce this inflorescence any other way.  An organism’s DNA provides the ‘blueprint’ for growth and the ‘specs’ for its component parts, as well as the means to create them. The hormones and enzymes work within established biochemical pathways as both switch and signaling system to redirect growth from one process and pattern to another.

With the onset of flowering, the growth of the massive peduncle, the process of the sequestration of carbohydrates is reversed and the Agave’s cells begin breaking the stored starches down into simple sugars to power growth. To do this it must also change the concentration and balance of enzymes which catalyze, or speed up this process. The plant is then producing enzymes that are essentially digesting its old structure, its leaves and the carbohydrates stored in its piña.  It is a metamorphosis akin to, but not as total as that of a caterpillar transforming into its adult butterfly stage.  The Agave’s now amped up growth rate is no longer limited by photosynthesis, nor by a low concentration of the necessary enzymes. Whatever water it requires it draws from the soil and its own tissues.  Additionally, to provide the ‘materials’ large molecules like proteins, no longer needed in the old structure, can be broken down by other normal functions within cells, into their building blocks, amino acids, polypeptides and simpler proteins, which are then carried via the plant’s vascular system to the Agave’s growth center, in its apical meristem, atop the rising peduncle.  It is efficiently and organically recycling and repurposing its own tissues.  It doesn’t have to synthesize all of these from ‘scratch’.  The meristem and the accompanying zone of ‘differentiation’, is where the reforming process takes place.  All in all this is a magnificently balanced, on demand, system of cellular, biochemical processing plants and ‘factories’, housed in its cells, transforming its original structure into the inflorescence, while utilizing the energy it has scrupulously stored.

[Nov. 30 The peduncle has radically slowed, reaching 128.5″ as measured on the 28th, having grown about 6″ over the last month, while our pattern of a drier than normal Fall continues.  On this date we will experience our coldest temperature of the winter at our garden, 26.4ºF.  It will be a milder than normal winter, for us…and drier! Sept. saw only .81″, half of normal, Oct. 1.55″, again half of normal, and Nov. 1.34″, about 1/4 of normal!]

Agave, like all plants, can sense their surroundings as well as their internal ‘state’, their level of health, readiness and fitness. It then uses this information to signal its many cells to regulate its growth, all of its metabolic processes. They ‘have to’ do this to live. They are responsive to both their own environment and their internal state. This ability is not unique to Agave, but is shared by all organisms. Organisms are incredible self-regulating organic structures…its expression in Agave is unique.

All of this transformative process puts the entire structure under stress.  Because photosynthesis is not the central driver of all of this even chloroplasts, with their chlorophyl, are not as essential and maybe sacrificed.  When they are the underlying anthocyanins, which provide defensive capacities to the plant, can begin to show through and their red color becomes more prominent. In Mexico the entire structure of this species often turn bright red during flowering.  Anthocyanins are not suddenly created, but are there all along masked by the chlorophyll.  This change in coloration is much like that of leaves of many deciduous plants with the arrival of Fall when chlorophyll and its constituent ‘parts’ are drawn back into the permanent structure of the plant, conserving resources.  How ‘red’ Monte turns may be lessened because of our richer soil, the capacity of its starch rich storehouse, its ‘heart’ or piña, available soil water and/or the intensity of the sun, which is significantly less at our more northern latitude, some 20º or so further from the equator.  These may work  together preventing the plant from suffering so much stress during the flowering process and, consequently, result in less loss of chlorophyll…a speculation.

• Monte added an additional 2 1/2” by the end of January.  All chemical reactions, such as those involved in growth, slow with the cool temperatures.  During its winter ‘hiatus’ another pattern of growth is set into place, this time to produce the far more complex structure of the branches and buds that will form the ‘crown’ of the panicle.  Plants, produce embryonic structures, sometimes quite early in the flowering process, tiny ‘models’ which will be released at the appropriate time to form the ‘branches’ and flowers to follow.  Agave are determinate growers, they have a ‘preset’ size and will not continue expanding over time.  (Other plants can be ‘indeterminate’ and will continue expanding as long as resources and conditions permit.)  I don’t know whether these form while the primary peduncle is shooting or during this winter ‘hiatus’.
Agave montana has a very stocky inflorescence for an Agave. I suspect this is because of its high mountain origins, near the hurricane prone Gulf of Mexico, a taller, ‘flimsier’ structure might topple and the individual would fail to produce seed, its only means of reproducing itself.

[Dec. 6 
Monte has ‘climbed’ another 1/2” over the last eight days, 129”…wohoo! Our temperatures have continued to be in the normal range having dropped below freezing only twice in that period.  Precipitation continues on the miserly side as well having received only .07” in the first week of December…we should be averaging about 1/6 of an inch, or .177” per day…so we continue to be dry.  (December would turn out to be only a half inch shy of normal at 5.05″ as we received the benefits of a 4 day ‘atmospheric river’, still less intense than predicted.) Those of you who don’t know, the Maritime Pacific Northwest is famously dark, dank and gloomy over the winter months, not that we are that wet, but the wet can be unrelenting, often ‘misting’ for days on end, the sun lost behind dense cloud cover, ‘perfect’ for those suffering the depression of Seasonal Affective Disorder and for fatal extremes of several foliar and soil borne fungal diseases many winter/dry loving succulents are subject to.]

[Dec. 22 
The winter solstice arrived with our shortest day of the year.  At 46º north latitude we are north of Chicago, Detroit, Minneapolis, Montreal…almost 2.5º north of Portland, ME, all those places with frigid winters due to the arctic air dropping down out of Canada.  On that day we survived on  8hrs and 42mins of sun, which at noon reaches up only to 21º above the horizon.  Compare this to the conditions that hold in its more southerly native range on that same day, with a day length of 10hrs 32mins and a noon time solar elevation of 42º, twice as high, and you can begin to understand the impact. 
(Portland won’t reach an angle of 42º until March 12!  An elevation we dropped beneath back on Sept. 28 when we first noticed flowering!!!  At the end of October, when most of the primary peduncle growth was completed, the sun had its height reduced to 31º above the horizon.) 
Along with these ‘numbers’ comes our lowest light intensity and insolation, or daily gain of energy.  This has to effect photosynthesis and likely effects the plant’s metabolic activity, beyond mere temperature, recall that plants are highly responsive/sensitive to, the conditions they grow under.  In some, like Onions, flowering is strictly tied to day length and late planting can result in the production of small bulbs.]

Christmas Day

• At the end of January we noticed that the terminal section of the peduncle had begun to ‘swell’ slightly, the covering bracts being ‘pushed’ outward gradually making the top look more bulbous and irregular. This mountain species never went dormant, the cold only slows its rate of growth.  January was oddly wet for us, which is normal in its own way, as we swing between maritime and continental influences.  We received 8.66″ of rain for the month, about 175% of normal.
• At this stage the overall height was 131”. Over the next month it would only add 1” while the early bud development continues.

Growth of the panicle’s crown

The first ‘branch’, secondary peduncle, emerges from the main stem at 10′ 2″, 122″, a height the peduncle reached on Oct. 28th…though active extension of the secondary peduncles didn’t begin to show until Jan. 30, when it was another 9″ taller.  Remember that undifferentiated cells are produced by the meristem, which later develop into the specific cells needed and attain their ultimate size.  Embryonic buds and tissues form, preceding secondary peduncle extension.  These develop slowly, their more active extension and development delayed while the internode between them lengthens separating them along the still rising main stem.  The branches and buds develop progressively upward, all the embryonic buds initially held in a greatly compressed structure.  As it grows the meristem continues ‘riding’ upward, initiating each branching, with determinate, limited, meristem, associated with each branch and bud, growing out a ‘pre-set’ distance or pattern to completion, while ‘preparing’ for the next round upwards in a spiraling pattern, initiating in sequence.  The number of branches and buds are determined by genetics and growing conditions.  Buds cannot just keep forming and developing indefinitely.  

[Feb. 13
I’m keeping an eye on Monte and pulling the ladder out once a week to examine it more closely. Progress is still slow, but the pictures show an increase in the reddening of the bracts around the terminal…it is also ‘swelling’ slowly, adding another 1″ to its circumference at its widest point. At the tip, the apexes of the substantial and somewhat rigid, bracts are ‘opening’, spreading wider, no longer able to stay closed with the activity beneath. They hug the swollen belly of the terminal as tightly as they can, while below the bracts gape, slightly, here and there. People keep coming by asking when it will actually be in flower…I don’t know, but change is afoot, as day length continues to increase bringing gradual upticks in the average daily temperature.

Feb. 21
Breaking Monte report: Still alive…and growing. 132”, 11’ tall and has added 2” to its circumference making it 25.5”. A high of 60F today!

Feb. 29 (Leap Year!)
Progress is still slow with Monte adding maybe a 1/2” To its circumference.  It does seem fuller, rounder, with the tips of the bracts on top in a slightly more open position.  Here at my house rainfall has been slightly less than half typical for February with the temperatures weirdly normal, only one freezing day down to 30°.]

Over March Monte added another 4” reaching 136” in height. Extension of the panicle’s ‘crown’ continued adding another 2” over the following two weeks. The pace is increasing. By April 25th the ‘crown’ has extended another 20” to 158”! I measured it at 168” five days later on the 30th and 170” four days later. There is still room for more as the top most bracts and their contained buds continue to develop. In the wild these don’t ever quite reach 15’ or 180”…this one here, with our richer soil, is on its way to besting that!
• The bracts are modified leaves. As in the rosette they emerge in a spiraling pattern.  As the stem extends upward each successive bract reflects the same ‘rotation’ only there is a substantial extension of the internode, in between, spacing these out several inches. On this species the bracts are large, overlapping, imbricate, uniform, along the entire length of the peduncle. On many or most other Agave, especially the desert species, the bracts are much smaller, attenuated, and don’t come close to ‘sheathing’ the rising peduncle shaft.  Some botanists speculate that the thick bracts serve an insulation function protecting the buds and dividing/growing meristem tissue just below the terminal from which all growth is initiated.

[Mar. 4
Monte is coming down the back stretch, preparing for the final kick. The top most bracts are spreading open, but not enough to see beneath, especially on the south side.  You still can’t see the buds and expanding secondary peduncles!
We’ve had a mild/normal winter, temperature wise here, with scattered freezing temps, the coldest in late November and only once, at 30, in February.  As I’ve said before most of Portland tends to have lower lows than we have here locally in winter true again this last winter. Days are markedly longer and the sun significantly higher in the sky in comparison to that experienced on the winter solstice 73 days ago, the sun 17º higher at 38º at our solar noon today with a day length of 11 hours and 20 minutes vs. 8 hours and 42 minutes then. What’s the determining factor in the restarting of flowering?]

[Mar. 14
A bit of snow last night, just enough for the wet gloppy stuff to stick on plants, and bend them over. Not Monte though, the sturdy specimen that ‘he’ is, is still unperturbed! 33.8ºF was our low. The Oleanders, being pliable evergreens, were weighted down.]

[Mar. 25
I haven’t measured Monte for awhile…and he’s grown! Now at 136” tall, thats 4” taller than it was a month ago on Feb. 21st. The terminal is definitely swelling as it is now 31” in circumference, up 4” from 2 weeks ago. There’s an older Tom Waits song, ‘What’s He Building in There?’ that comes to mind….]


[April 21
Pivotal moment here for Monte! Last evening the light was wrong to really see, so I went out this morning and found this. A southeast facing bract has separated enough that I could climb up and see inside! Day 205 from first notice.  Agave bloom progressively from the bottom up in a spiral pattern. This will be the first flowering branch, or secondary peduncle, in the inflorescence! The buds in this cluster are tightly closed and should remain so until the branch is fully extended. On my other flowering Agave all the flowers on a given branch opened on the same day. So flowering itself should follow a spiral pattern upward! Individuals of this species have variable inflorescences with regard to the length of their secondary peduncles, some stubby others less so…time will tell.]

• I measured the circumference of this expanding ‘bulb’ at roughly 43”, about 13.7” in diameter. It was 23” around, 7.3” in diameter, when we first noticed its ‘expansion’ in late January.

An artist, and new friend, made this homage to Monte and we drove up into NE on a pilgrimage of our own to see it!


[April 28
Monte’s rise to minor local celebrity status keeps increasing.  It has become a bit of a phenomenon with more people making daily visitations now to check its progress, one family, with two young girls, come every evening, a pattern that would continue. This has become a teaching moment!  Monte has risen to 158″!]

[April 30
Monte is growing noticeably everyday! Measured this morning at 14’ even, 168″. The crown (the ‘bulb’) of the inflorescence is 4’4” tall (I was measuring from the ‘base’ of the flare, below the lowest branches, so if someone’ is checking my numbers they may not seem to add up.  The position of the branches, however, do not change…they are not ‘pushed’ up higher by a lengthening lower stem.  Height is determined at their emergence from the meristem.) The ‘oldest’ individual buds are beginning to separate and elongate from the others in the cluster (Did I just contradict myself? New ‘undifferentiated’ cells form from the meristem.  There is then a ‘zone’, if you will, where these new cells elongate and differentiate, becoming their ultimate type and size!  This involves a complex process of methylation in which particular gene sequences are ‘turned’ off to form specific cells, an epigenetic process, ‘beyond or above genetics’, most common in the cell development of almost all organisms.) The cooler north side is ‘lagging’ behind the south by a week or week and a half.]

[May 2 
We’re glad today, Saturday, is rainy!  That should limit visitors a bit, though they’re already coming by this morning. It’s been kind of like having an open garden…every day and most visitors are non-gardeners, though many are. Word of mouth, FB, Instagram, Tweets, Next Door and local Portland Reddit pages…social media is abuzz and it’s just accelerating! I’m hanging more signs and trying to keep people out of the beds!!!]

• Flowering, like all other growth in Agave, develops from the bottom up in a spiraling pattern, normally, following the Fibonacci series of mathematics, as do many structures in nature, from the Nautilus Shell to the arrangement of seeds in the head of a Sunflower. There are differences, glitches, which commonly occur in living organisms, while the underlying pattern remains true.  Here, the warmer south side, advanced about a week and a half ahead of growth on the north/shaded/cooler side, causing the lopsided appearance of the flowering panicle structure. This caused the ‘crown’ to curve northward, the entire south side outgrowing the north. I expect that the structure will even out over time, as the north ‘catches up’, the branching  eventually taking on a more radially symmetrical structure.

[Side note: The structural pattern of development is called ‘phyllotaxy’.  There are several different patterns  each following specific ‘rules’.  Spiral phyllotaxy exhibits a structure in which each successive branch or leaf/bract along the stem forms 137.5º passed the previous.  Looking down, this ascending pattern rotates counter-clockwise.  This follows a ratio based on the Fibonacci series, a set of numbers, beginning with 1 each successive number the sum of the two previous numbers, 1, 1, 2, 3, 5, 8, 13, 21, 34 etc.  The ratio is written 2/5, then 3/8, next 5/13 and on.  The first number is the number of rotations, the second the number of branches ‘passed’.  So, 5/13 means that as you ascend the spiral when you complete 5 full rotations you have passed 13 branches.  The higher you go the more precise the ratio becomes.  Monte has 34 ‘branches’ including the terminal.  This means there are 13 rotations as the branches ascend. Nature repeats successful patterns.]

There are still differences.  On May 14 the more northerly peduncles were still slightly shorter, and, seemed to be ‘bending’ toward the south, toward the more intense light as they extend. The lowest most branch curved severely downwardly and to the south, pointing almost southerly. This branch developed more than a week late so the progression was uneven. The buds/flowers in this lowest cluster arcing even more southerly and upward giving them an odd flaring pattern that is not repeated in any of the more pillow like clusters. I suspect this may be due in part to our more northerly latitude with the sun rising to a relatively low elevation above the horizon during this stage. In its native Mexico the sun never retreats so far south nor is it so limited in its elevation, rising to nearly straight up overhead in summer. A ‘higher’ sun would tend to support a more symmetrical development around the entirety of the inflorescence.  I suspect that other Agave, particularly the paniculate flowerers with longer branching, will exhibit this same characteristic at northerly latitudes, at least the larger ones.


• Each secondary peduncle holds a cluster of three bunches of flower buds. Before these flower, they will have to extend and separate, at least a little, to give each bud enough room to open. This may involve another, tertiary branching, to separate the three bunches. At first I thought that this speculation was wrong. It wasn’t until early July, when I climbed up and was able to clear away the aborted ovaries that the underlying structure was visible. Two short branches, maybe an inch, split off.  While not as pronounced as I thought it would be, it was there. Separation is also accomplished in two other less expected ways, first by the lengthening of the pedicels, corolla tube and flower parts, which tend to flare individual flowers out and, secondly, separating them ‘temporally’, in time, through the more random ‘staging’ of each bud’s opening allowing flowers to go through the various stages of their flowering while others wait, literally, below. From the ground, this gives the effect of a longer bloom period. In reality each flower has a relatively short life, its anthers beginning to shrivel and dry in four days or so, their pistils, the styles and their stigmas, within a few later, making room for the next wave of flowering below. The process is somewhat ‘random’ as it does not occur in organized waves or a pattern in a cluster. From above and close this staging is obvious.

Many visitors were curious about whether this could successfully self-pollinate as there are no other Agave of any species in bloom here.  I, of course, offered them a long answer.  Agave flowers are ‘protandrus’, their pollen bearing anthers ripen first, declining before the female pistil matures. An agave flower cannot pollinate itself. It requires another flower in the proper stage. This does not mean another Agave plant.   This species does not form clonal colonies and can be quite widely separated so it has adapted to these conditions.  The flowers of an individual Agave open and mature over an extended period. Somewhere on a flowering Agave there will be mature anthers and stigma at the same time permitting pollination and successful fertilization. 

To aid in this there are 20 some Hummingbird species in this Agave’s home range and they may play a pollination role. There are also two species of nectarivorous bats that may. Some visitors new about the bats.  (One visitor works with Bat Conservation International on a project with government agencies and farmers to educate and conserve the threatened species and their required habitats.)  The bats fly a migratory route which I suspect wouldn’t put them in this Agave’s range during its bloom period, but….Bright flowers such as this Agave has tend to serve more to attract hummingbirds, bees and other day time flyers.  Lighter, more reflective blossoms, tend to be more attractive to bats and moths which fly at and after dusk (This is not always true). Bees and lepidoptera may play a role, and I expect that they will be important here for successful pollination. (We have very few butterflies here in the city and though I only went out a couple of evenings to watch, we didn’t see any moths.)

[May 4 (crowd frustration beginning)
Imagine that you were growing the world’s biggest turnip in your garden, the root top bulging up out of the ground like an exaggerated ottoman, the tops waving above your head like green stemmed trees and everyone came to see it…crowds of people 10, 50, 60 people at a time, in a never ending parade, all vying for their moment to pose next to your turnip!  And their questions! 
Is it yours? Did you plant it? How big is it?  How did you grow it so big? How far down into the ground does it go?  Will it get bigger? Wait…it dies?  You mean the top?  The whole thing? So, it won’t come back?  You try to be patient, but it gets harder and harder as you keep answering the same questions.  You remind yourself that this is a teachable moment, only the moment doesn’t seem to ever end…and you tire…especially when the question askers don’t seem to pay attention, as if you’re explaining an impossibility…and they ask it again!
And then you get up the next day and do the same thing all over again…with even more people. 
Many of them thank you, and that’s good…for growing it and opening the garden to everyone and this seems a little weird to you.  You tell them that you didn’t do this for them.  That you just like growing turnips and would grow them whether anyone came at all.  And to some of these people, you say that this has all become a circus and a bit too much and you appreciate how truly amazing your turnip is, but the public reaction strikes you as a bit crazy, its become a thing with a life and momentum of its own that doesn’t seem to have anything to do with the turnip, and you wonder why people don’t grow their own turnips.
You shake your head at the almost manic behavior of some. You’re more than a little incredulous…and, you’re getting tired.  You’re losing your enthusiasm.  You’d rather just measure your turnip as it grows and make notes.  Many of these people don’t seem very interested in what’s going on, they’re merely caught in the current…some are though, interested I mean, and you try to spot them and focus on them so that the others don’t keep asking the same question.  You wish that some would just listen, but you tell yourself that some people really have no understanding of turnip growth, or even growth of any plant and you sigh and answer again and wish the world were different.
You begin to question the phenomenon of celebrity, especially of turnips, and how wonder and awe, something you regularly feel, gets somehow lost, transformed into…whatever this is, by social media FB, Instagram, NextDoor and Reddit, amplifying, accelerating, exponentially the public reaction to your turnip, as magnificent as it is, it is still, after all, just a turnip.

And then I wonder what tomorrow will bring?]

[May 6
The Monte story began slowly this morning, at 6:30am when I went out to find four visitors already here…the numbers kept increasing, especially once the drizzly rain relented. 
By mid-morning it was a crowd, I told a woman to leave, that she was not welcome.  She had been yelling at my neighbor, calling her a bitch, and not in the familiar, social way, you sometimes hear today.  More was said, angrily.  My neighbor is immune compromised and has placed signs all around her place….As the visitor stomped away to her car, she flipped us off!
I’ve just come in from talking to a PBoT inspector, Portland Bureau of Transportation.  Their office has been receiving traffic safety complaints! The inspector was stunned.  He was sent out to observe and report back to his office.  He wasn’t sure what could be done or even what I could do, Monte is in the parking/hell-strip which is owned by the City.  Julie later pointed out that the city could cut it down to remove the hazard…but they aren’t normally so clumsy and blunt…but with the pandemic?  Buses have had to stop, honking to clear people from the street.  Jerks with blasting car stereos have driven slowly by.  Bikes, we have painted bike lanes here, often have to brake and swerve to avoid people.  Others stop in the traffic lane to take pictures, impeding those behind….Some have even stopped their cars in the traffic lane and gotten out to take their pictures!  The inspector left after also taking pictures with his phone for his wife!
I haven’t been to a grocery store in well over a month…..I was going to set up for a time-lapse of some opening flowers, but I didn’t want to go out again, setup and leave my camera up on the ladder with all of the people around and I wasn’t going to stay on the ladder to babysit/guard it.  No time-lapse.

(sigh)

Oh yeah…Monte’s lowest secondary peduncles are beginning to pop!]

• When actually flowering the three red sepals of each flower, which enclose the bud, separate. All of their flower parts are in multiples of three.  As they open a sliver of bright yellow/green expands to fill it, the sepals curving outward to reveal the small yellow petals within. The pollen bearing anthers extend their filaments, from the folded positions they held inside the bud, to well above the flower’s corolla. Later the stigmas, the ‘fertile gateway’ to the ovary, emerges, and later still, matures, opening and releasing a sticky wet substance to help capture pollen. Flowering proceeds progressively, but somewhat unevenly, up and around the plant. By the time the flowers at the top of the panicle are open, those at the bottom, will have finished long before.

[May 8
Monte, at 6:00am…getting out before the crowd…nope, people were already coming.
The flowers started opening two mornings ago… this plant is defying my expectation. While the overall structure is developing symmetrically and progressively upward in a radial pattern, it’s timing is much more random. This morning flowers are open in the clusters on four different south facing branches though not even on the earliest one have all the buds opened. It’s hard to focus on a single set of anthers but in the oldest cluster some have dehisced this morning splitting and turning inside out to reveal their sticky pollen. I hadn’t checked the formal description and was expecting anthers longer than the 3/4″ length of these. I am curious when the bees will discover it and when or if the Anna’s hummingbirds will. At some point I will climb the ladder again if there looks like there’s activity and set up a video or time lapse.]

[May 9
Second morning in a row with a typical summer low temperature, yesterday 62° this morning 65°. Combined with yesterday’s high of 82° and an expected 87° today, progress has really sped up.
The highest section of the inflorescence is really separating and defining itself. Pictures show the ascending radial pattern of the branching structure with the lengthening of the internodes. We saw neither hummingbirds nor bees around it anytime we’ve checked. Many more of the anthers have matured this morning so I’m hoping pollinators will be attracted, though because of the flowers protandrous nature, none of the female stigmas are yet ready. Still, it would be nice to see pollinators.]

[May 10
Monte has reached 180”, 15’, today and still has potential to go higher! I climbed up to measure a typical cluster at the end of a ‘branch’. They are looking very ‘pillowy’. An individual flower with its pedicel, tubular corolla, exserted stamens and pistil is about 6”. They arc out forming a pillow roughly 12” long, 8” across and 8” high at the lower ‘levels’. Weirdly, one peduncle on the north has decided to curl curiously downward.  Flowering is proceeding unexpectedly and rather erratically, in what is to become the normal pattern.]

[May 13
This morning Monte has stretched up to 15’2”. At its widest the crown is about 50” across and 60” tall…with some to go!  It’s cooled down into the 60’s with a low of 49 this morning and has been showery. We had almost hit 90ºF and flower development was proceeding rapidly.  Still no sign of pollinators….Don’t really want to climb up and spend the time hand pollinating!

[May 15
Signs of collapse as Monte continues to consume itself recycling materials and mining carbohydrates for the energy they provide to power growth. The margins at the base of the rosette’s leaves are waving, undulating, as their tissue loses water, the surface cracking and a few of the leaves are starting to collapse onto the ones below. It would appear that this is not gonna be a ‘pretty’ or graceful way out. Additionally, as the plant loses more chlorophyll, it will lose its green color and the red, throughout the plant, will become more prominent, or so I suspected.]

[May 16
The honeybees have found Monte! The first individual buds opened in the lowest cluster on May 6 so it’s taken 10 days for the bees to find the agave flowers. I’m sure the last two or three cool wet days added difficulty to their locating it.   The lowest cluster, as well as many of the other flowers, probably won’t get pollinated as they’re stigmas have already passed maturity. Now that they’ve found it, as long as the weather continues favorably, most of the ovaries should get fertilized.  Seeds should be on its way assuming nothing happens to interrupt its maturation.]

[May 18
Monte’s ‘show’ isn’t about it’s individually gorgeous flowers, it’s the mass effect of their inflorescence, it’s size, contrasting colors and structure. A Single flower, with it’s spare, cup shaped corolla forms a simple crown with its shriveling and darkening sepals. Each has six anthers and a single tripartite stigma on the end of its style. The style is attached at its base to the flower’s long ovary, which I show here roughly split with my pocket knife. When pollinated a pollen tube grows quickly from the stigma down through the style to one of the chambers within the ovary where fertilization happens.  The seeds then go on to mature here swelling the ovary.]

[May 19 (inspired by a FB interchange)
Do not shed any ‘tears’ for Monte! I think it’s interesting that so many Monte followers are way more worked up about this than I am. I’ve lived with it for about 19 years, watched it all of the way. It has lead a good life. survived a car accident, which completely uprooted leaving it damage in the middle of the sidewalk, and is flowering beautifully as intended. Like all living things, it will now pass and I’m okay with that. It’s passing opens a path for what come next. It feels right and is the natural way of things.
If you feel it proper to memorialize Monte in some way then do something notable in your own garden, something along the public edge for others to appreciate!
Think of Monte as the plant version of a Salmon that lives its life in the ocean and then returns home to spawn, not feeding once after it re-enters freshwater, spending everything it has to reach the waters of its birth. It will never know its progeny!  A complete and utter act of faith!!!
Flowering and death are inextricably linked in an Agave and many plants, as they ‘spend’ their energy and ‘flesh’ to produce their massive inflorescence in a single burst of exuberant promise.
Gardening offers us lessons for our own lives, if we are open to them.  It is not just about creating something pretty or producing something good to eat, though that is part of it.  Any plant is wholly committed to its way of life, sadly, unlike so many humans.]

[May 20
Some more Monte shots on yet another drizzly morning giving you some views of the crown of the panicle up close. Up at the top the branching is much shorter than I thought and so we are arriving closer to the end with one of the highest most clusters displaying open buds. Yesterday some visitors spotted an Anna’s hummingbird feeding. Sadly, I didn’t get to see it.]

[May 22
Whoa! The sun actually came out this morning for a few scattered moments!  Blue sky and Monte!
Those of you who have been following Monte, might want to check out this page on the flowering of the Agave montana at the Ruth Bancroft Garden, in ’18.  It is the first/only other one of its species that I’m aware of to bloom in the continental US and its performance was very different in multiple ways.  Seedling variation? Growing conditions? Latitude?  I don’t know why!  Ruth Bancroft was an intrepid and knowledgeable collector of succulents, among them Agave.  Her garden, her legacy, is amazing and is open to the public in Walnut Creek down in the Bay Area!]

[May 23
Monte report: While the flowers in the bottom clusters are completely collapsed, the top most have yet to begin on this the 17th day since the first bud broke! It is hard to accurately measure with a tape measure from the top of a ten foot ladder, but I think I’m within an inch…Monte has reached 190”, 15’ 10”!]

A friend did a little ‘fly by’ for me, a drone shot from overhead! Thanks Grant Joseph

[May 26
Monte continues to bloom out. Buds are beginning to show at the very top while the lowest cluster is completely bloomed out, male and female parts collapsed, drying and twisting, intact, but even there many of the cups at the base of the corolla are, apparently, still functional containing nectar. I could see bees crawling down inside to feed.]

[May 28
The highest cluster is opening. My measurements aren’t super precise, but it would appear that Monte has reached 16’2”…from the lowest branch to the tip top, the ‘crown’ itself measures right at 6’, 72”!  Recalling its spiral phyllotaxy, its 34 secondary peduncles, branches, are separated vertically by a little more than 2″ as they wind up the crown 13 times each rotating 137.5º.]

[May 31
Monte on a cool, lazy Sunday, it’s spent flower parts hanging on! Even many of the collapsed anthers are still heavy with pollen. Topped out at 16’4” to the anthers at the very top.
At the same time there are large flies everywhere! In the flowers, the bracts and leaves of the rosette below. Dave, my friendly neighborhood beekeeper, tasted it and pronounced that the flies are feeding on the nectar spilled from the flowers! Meanwhile Monte’s decline continues sacrificing tissue to the great flowering above!]

It wasn’t until May 31 that I first noticed that ovaries are being aborted and are falling to the ground in large numbers…but it is what I expected!  These often hung up in the clusters for several days, weeks, their tangled, leathery, flower parts caught up in one another, before dropping.  As noted previously, pollinators, in the form of European Honey Bees from my neighbor’s hives, were late to the pollen ‘party’, the first flower emerging on May 6, the first bees not arriving until May 16, well after the first wave of flowers in the lower clusters had completed their process.  Previously there were plenty of bees around, many of them swarming over my two Echium plants in full bloom 60′ to the east.  Eleven of the remaining 16 days of May had measurable rainfall.  Much of the period was overcast and cool even when it wasn’t raining, five of which were at or above 70º.  Five of the eleven flowering June days had measurable rain as well.  High temperatures in June then ranged between 61º and 83º.  So much of the time the bees had was not very supportive of pollination.  Much of the time they were no where to be seen.

Many people don’t understand seeds and their relationship with flowering.  They often see them as separate and unrelated as if the plant flowers and then the seeds spontaneously appear…inexplicable and unknowable plant magic….Some thought the aborted ovaries that lay littered all around were the seeds.  One guy asked me, with worried hopefulness, that if the whole structure toppled over wouldn’t the seeds still ripen? as if it was just a process of drying them or, I don’t know, like how many fruits lying around, separate from the plant can ripen.  I told him that at this stage the seeds are undeveloped.  They still must draw from the plant to produce the needed proteins, lipids and starches viable seed requires. These stages of seed development require that the plant is still alive, it is an energy intensive process and so the plant must still be connected and capable of metabolizing and synthesizing the needed molecules. Dead is dead and a seed separated from a plant cannot metabolize what it needs on its own. These materials must be produced, delivered to each seed, and the embryonic plant within the seed, developed first!  The individual flowers, having served their purpose as pollinator attractors, collapse.  Those in which this process was successful, carrying now fertile ovum, will become seed.  The fertile ovaries are what matter now.  All else falls away as the process of seed production, with its energy and resource demands, moves ahead, the remaining plant declining, having served its purpose.  How much fertile seed will be produced?  We’ll have to wait and see!

• Some Agave species may hold their spent inflorescences aloft for several years after they die much like trees…this one won’t as I will remove it once I collect seed.

[June 11
A look back.  It’s 266 days since we first noticed Monte was shooting/flowering. If I can assume that the earliest stage of peduncle extension was at about 3”/day, a rate consistent with its primary, observable, shooting period, then the process began 12 days earlier on or about Sept. 17th, 278 days ago. The last of the filaments, which support the anthers of the flowers at the very top, collapsed a couple days ago. There are only a few pistils still remaining upright.

The leaves of the rosette are also collapsing, still losing starches and proteins, which are now being sacrificed to the development of the remaining ovaries and the seed that they contain. The starchy heart, the piña, which has powered so much of the flowering, is becoming more observable. Measuring down from my twine marker on the peduncle, 5 feet above grade, the piña appears to be approximately 2 feet tall. The remaining leaves of the Rosette still make it impossible to measure the piña’s diameter.

Earlier on in this process I thought my plant, like those that flower in the mountains in Mexico, would turn red, but for whatever reason, Monte hasn’t. Our richer soil, the lower intensity of the sun here at 46° north latitude, the elevation angle of the sun is 68° here while in its Mexican home range it would be around 85°, almost straight overhead! The available soil moisture, or just genetics…it’s impossible to say. ]

Flowering has been completed, with the last pistils collapsing, on June 12.  The ‘show’ over, the crowds gone, the City has removed its traffic controls and Monte continues to slowly collapse.  It’s July 1 the leaves of the basal rosette continue to shrivel while the entire rosette ‘flattens’.  People still come by, some first time visitors, others bringing newbie friends enthusiastically trying to describe how amazing and beautiful it once was.

[July 6
I climbed the ladder a few times again cleaning out the clusters, removing the many aborted ovaries still clinging, to get an idea of how much seed may develop.  I inspected probably half the clusters from one to nineteen and they were quite variable in terms of the numbers of flowers they once held, none had retained more than 25% of their ovaries most of these considerably less.  For example, the south facing number 2 cluster, the second ‘branch’ ascending the stem, but the first to begin blooming, retained 6 ovaries and lost 108.  Just above it and another one of the earliest to bloom, the seventh cluster in the rotation, retained 9 ovaries while 150 aborted.  The first cluster in the rotation, facing NW, and delayed by a couple weeks, retained 19 ovaries.  The 9th, facing west, retained 24 while the 14th, facing nw retained 25.  The 6th, facing north retained 30 ovaries, the most on those that I could access from the ladder, while aborting 92.  Of the 6 clusters on which I counted both retained and aborted ovaries the totals were 65:685, so less than a 10th were successful.  Those averaged 125 flowers per cluster.  The number of flowers tend to reduce going up the spiral, but unevenly.  A generous estimate would be 100 per cluster or 3,400 total.  A ten percent success rate would yield 340 developing ovaries.  I think both of those numbers are high.  I won’t be able to get a more complete count until I cut the peduncle down, as it’s out of reach.]

Over my life as a gardener, and professional horticulturist, I have grown many thousands of plants and while several attracted attention in the large display beds I used to care for in our downtown Parks, none have attracted anything near the attention that Monte has.  The Bananas and Palms, maybe the Gunnera and Hedychium, stood out from the rest in the earlier years when I first started growing them.  People had lots of questions about banana ‘trees’ and how they didn’t think you could grow them here.  This  Agave montana produces one of the more spectacular inflorescences of anything that I’ve ever seen, not perhaps in its details, the flowers are after all individually very simple, but in its presence and the audacity of its growth.  The strategies that it utilizes to grow, mature and flower, aren’t anything particularly special in the plant world, but the speed and scale of its accomplishment is undeniably impressive.  Every plant possesses its own strategies for success, and follow their own particular genetic blueprints in an astounding display of metabolism, bio-synthesis and self-regulation, while being both ‘self-aware’ and coherent in terms of both their internal function and in their coordination with the particularities of their site conditions.  Most of us overlook plants.  But when one with the qualities of ‘Monte’ are present, such ‘Charismatic Mega-Flora’ cannot be denied.  It is one of the reasons I chose to pay particularly close attention to its whole process and did my best to do a little horticultural outreach, to take advantage of a teachable moment, because in our fast paced world, they do not come along everyday.  COVID-19 and the pandemic helped expand this window as so many found themselves with a lot more time on their hands.  Many were simply caught up in the almost carnival/side show nature that dominated much of the more spectacular phase of Monte’s flowering, but there were many also who seemed genuinely curious about what was going on before them.  I tried to meet that need….

 

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