I’ve been taking advantage of people, striking when they are most sensitive, hungry for anything that is outside of their homes and families…I’ve been hanging informational signage amongst Monte’s floral neighbors as they come into bloom, not all of them. Some will remain anonymous like my Aristolochia semperivirens, an unassuming Dutchman’s Pipe, that is only noticed by the more discriminating of visitors. Others issue stronger ‘calls’ and so signage seems appropriate. Many people are taking the time to read them or take pictures of them for later consumption or to make sure they don’t forget. Many thank me for them. Who thought ‘school’ could be so cool! Anyway here is what I’ve hung out in the garden. Some will come down as their season ends, like the Pacific Coast Iris, others are waiting in the wings.
My Agave is flowering. The ‘spike’ you see growing upwards is the ‘peduncle’, the main flowering stem. As it meets its maximum height ‘branches’ will form near the top, from beneath the ‘bracts’, the tightly adpressed leaves, on which will form the yellow flowers. It will form a panicle, a ‘candelabra’ like structure. Agave are monocarpic, meaning they only flower once and then die, after it produces seed. It is 20 year old. Many Agave produce ‘offsets’ or ‘pups’ that can be grown on into mature plants…not this one!
This is a mountain species from Mexico’s Sierra Madre Orientale, where it is found between 6,000’ and 10,000’…not from the desert. This species is relatively new to the trade and was only formally described in 1996, 24 years ago. 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. It can experience freezing temperatures and even some snow there in open Oak-Pine forest. It begins its flowering process in Fall, then ‘stops’ for a period during winter, finishing the process in Spring/Summer. Most Agave are tropical/sub-tropical plants from deserts and are grown here in pots. There are 200 or so species, 3/4 of which are endemic to Mexico, found only there, none are native outside the Americas. Only 22 species are found in the US, from California into Nevada, Utah, Arizona, New Mexico and Texas. 3 are native to Florida.
Portland and the Maritime Pacific Northwest provide challenges to growing any Agave species and hybrid. Agave are native where climates tend to have most of their rainfall in summer. Here we have dry summers and wet cool/cold winters…this is the opposite of what most Agave need and will lead to rot and/or fungal foliar disease that can disfigure or kill most Agave species. Siting considerations are extremely important. They generally require full sun and excellent soil drainage. Here good air circulation helps foliage dry in winter. Sloping sites also help with soil drainage. Tilting the plant when planting is helpful as it helps the crowns stay dry. Some gardeners plant these under their eves or erect shelters over their plants to keep the crowns dry over winter. Agaves will require some summer water to grow well especially if they sit in dry soil all winter and spring….
Many Agave are becoming rare across their natural ranges in Mexico because of development and agriculture, a cause which threatens so much of our own natural flora in the US and around the world.
This species is not used to make Tequila! In its home range Agave are pollinated by hummingbirds, insects and nectarivorous bats, bats which are non-native here.
(False Red Yucca)
There are seven species of Beschorneria, from forests of the higher mountains of Mexico down into Guatemala. This is the most northerly species occurring in NE Mexico, not far from the range of Agave montana. Unlike their cousins, the Agave, all but one of these are ‘polycarpic’, they can flower year after year. These form a substantial rhizome which spreads gradually when the plant is well sited, forming colonies. This one does so only slowly.
Another Asparagus family member, hardy through our zn8a, down to 10º for short periods, if you can keep the crown dry enough. This one struggles a bit and I have to remove a fair amount of rotting leaves every spring…I should move it and it would do better, but I haven’t…it wants better drainage. This particular site is a little wet close to our house which tends to concentrate rainfall a bit without any eave over hang to catch it.
As an open pine/oak forest dweller these are tolerant of relatively shady sites. Mine get some shade.
It’s inflorescence typically form these bright red stems with its sparse branching and hanging, narrow, bell shaped flowers. Part of their corolla is green.
At the top of my stone steps is a selection of another species, Beshorneria yuccoides ‘Flamingo Glow’, which has a buttery colored mid-rib on each leaf. from forests of the mountains of central/eastern Mexico.
(Tower of Jewels)
There are 70 different species of Echium and several subspecies, in the same family as the commonly grown Borage. 27 species are endemic (occur no where else) to macronesia, the Canary, Madeira, and Cape Verde archipelagos lying in the eastern Atlantic close to Portugal, Morocco and west Africa. While the continental species are all herbaceous, dying to the ground over the winter, all but two of the island species are woody, with permanent stems. Echium wildpretii is one of these two.
Echium wildpretii can grow as high as 10’ in its home territory. It is generally a biennial, flowering in spring here, though sometimes, it can ‘wait’ and bloom the third spring. It is monocarpic, dying after producing seed. This plant is just under 9’ and is the tallest individual I’ve ever had in the 15 years of growing this. The plant grows in the ravines of Mount Teide, 12,198’, a volcano on Tenerife, 28ºN latitude, in the Canary Islands, so it has a very restricted range. It requires full sun and arid/dry conditions. With our much wetter winters it is best that you provide this with very good drainage as growing them in cold winter wet soil will decrease their cold hardiness and could lead to rot. Plant on south facing slopes and retaining walls with good air circulation. It is marginal, said to be hardy down to 23 °F.
The species E. pininana, the other Macronesian herbaceous grower, goes to 13’ having much the same form with blue flowers. E. candicans is a short lived woody shrub, which grows to 6’, both are grown here as well. In California these two and others are common some often escaping into the wild and crowding out native species. Here, these are marginal and survive only in protected areas killed by normal to colder winters.
Check my blog at Garden Riots. Annie’s Annuals sells several of these: https://www.anniesannuals.com/search/?q=echium
Grevillea x ‘Pink Pearl’
Grevillea is a genus of 360 species of flowering plants native to Australia and north and west to the Wallace Line. They vary from ground huggers to a tree over 100’ tall. They belong to the Protea family which includes many bizarre and large cut flowers used in the florist industry. They are pollinated by many Lepidoptera, butterflies and moths as well as by Honeyeaters, a group of nectar feeding birds native to their home range related to South African Sunbirds, but not at all to our Hummingbirds. Hummingbirds and bees visit these here.
Most Grevillea are not hardy here in the NW so choose judiciously. To find reliable plants check out the offerings of Xera Plants on SE 11th and or take the trip out Sauvie Island to Cistus Nursery, they have a section of Australian plants. There is a great review of NW hardy Grevillea at Desert Northewest’s site, https://www.desertnorthwest.com/articles/grevilleas_revisited.html
Grevillea readily hybridize. This is thought to be a hybrid of G. juniperina x G. rosmarinifolia. If you give it what it wants it is hardy down to 20ºF, maybe lower. I planted this one 6 years ago here. One winter, ’16/’17, I lost about 1/3 of the top. That was Portland’s fifth coldest winter ever in terms of number of days with freezing temperatures…so not typical. (https://weather.com/storms/winter/news/portland-oregon-worst-winter-city-2016-2017) I suspect another degree colder or with another day of sustained freezing, I would have lost the entire plant.
These are relatively fast growing and can take a hard pruning. In Australia these are often used as hedge plants causing them to grow densely with their pokey needles, quite a barrier! I prune mine regularly to limit its size while retaining its softer look with drooping branch tips.
These are sun lovers and require well drained soil here. They are drought tolerant in the Pacific NW requiring no water after establishment. It is essential that should you choose to fertilize that it include NO PHOSPHOROUS!!! Phosphorous is plentiful in our soil already and adding anymore can prove deadly to Grevillea and also to most all members of the larger plant family. These come from regions with phosphorous poor soils and are very well adapted to searching it out, so…don’t add any!
x Halimiocistus wintonensis ‘Merrist Wood Cream’
This Rock Rose is a hybrid between two different genera Halimium and Cistus, a relatively rare even as species from different genera aren’t generally capable of crossing successfully. The parents are both Mediterranean plants and this plant benefits from growing under like conditions, warm to hot, dry summers and cool/mild and relatively wet winters.
This plant has grown here for 10+ years on this south facing slope in unamended soil. It benefits from a light cutting back after flowering to help keep it compact and to keep it from falling/splaying open. All of the Rock Roses have a tendency to splay open with time here as our rich soil tends to push them to produce extensive soft growth. Don’t cut these hard, below healthy growth, if you do you are likely to end up with dead stubs unable to resprout. I’m planning to take cuttings of this, root them and replace this plant as it has gotten rather ‘leggy’ over time.
There are many fine Rock Roses available from these two genera that can be grown here.
Lobelia laxiflora ssp. angustifolia
This Lobelia, with its narrow hot red tubular flowers, from Mexico, is reliably evergreen here except over our coldest winters, which can kill it to the ground, but from which it springs back. It often blooms for 7 months or more in the year. As you might guess it is attractive to hummingbirds. This plant is rhizomatous and in too good of conditions with summer water, has a tendency to spread, though it does so compactly. It is better ‘behaved’ under drier, more spare, conditions.
Lobelia are a large and varied genus with 415 species occurring primarily in tropical to warm temperate regions. I also grow the less commonly grown species type, sometimes called ‘Candy Corn Flower’ with broader leaves which is less robust for me here, but showy in its own way.
I grow Lobelia tupa on the east side of our house. It’s a large growing Lobelia from the Andes of Chile with hooking dark red large flowers. I have others on my list including the large pink flowering species, L. bridgesii, to acquire and am somewhat enamored with the ‘Tree Lobelias’ limited to the Hawaiian Islands.
Mimulus aurantiacus ‘Jeff’s Tangerine’
Sometimes known as “Sticky” or “Bush Monkey Flower” this plant is native from SW Oregon down through most of California into Baja. A ‘sub-shrub’ this has a somewhat woody base from which sprouts softer herbaceous stems that carry the leaves and flowers. Found from coastal bluffs east into the Siskiyou and Sierra Nevada mountains, these are ideally suited to our mediterranean climate with its summer dry/winter wet precipitation pattern.
Typically, where I’ve seen it growing in situ it is taller than my plant with a much more substantial woody base. At Point Lobos, on the central California coast, these can be over 4’ tall and form impenetrable thickets. Here with our rich soil it grows more lushly and flops. My plant is ten years old and will bloom all May through September in waves, almost never completely out of flower.
Place it in full sun. Mine receives only sporadic summer water. It grows in unamended soil on a south slope so it has good surface drainage. It benefits from free air movement and good soil drainage. There are several color forms available from specialty nurseries.
Pacific Coast Iris
There are 12 Iris species in the group native to our region stretching from southern California northward into Washington state, in a narrow band between the ocean and the Cascades and into California’s western Sierra Nevada. Most of these are limited to California and southern Oregon to areas that receive enough rain and are often limited to places closer to the coast. The Willamette Valley and Washington is mostly limited to one species, the deciduous, woodland edger, Iris tenax.
Hybridizers have taken advantage of their tendency to cross and are found in a wide range of jewel like colors, white, to yellow, red, russet, blue and purple. The hybrids are evergreen. These must generally be searched out as their production is relatively low because these Irises are difficult or impossible to grow anywhere else in the country because of soil and climate differences too far out of their ability to adapt.
The hybrids are drought tolerant in our western gardens. Plant them with plenty of sun, then water to establish. Don’t plant them anywhere where the soil remains soggy into the summer, they need to dry out. It is important to leave them undisturbed after planting. If you choose to move or divide them, wait until the fail rains, when they are producing new roots. They will likely die if messed with during the summer. See my blog: gardenriots.com.
Sphaeralcea x ‘Newleaze Coral’
The genus Sphaeralcea is native/endemic to the intermountain west of North America, occurring between the Rocky Mountains and the Cascades and east of the Coastal mountains of California. Some can be found in eastern Washington, Oregon and Idaho on south into northern Mexico. They like sun, heat and thrive in poorer mineral soils and are drought tolerant here once established.
‘Newleaze Coral’ earned its garden pedigree in the UK and is a stellar performer here in xeric beds. Sphaeralcea is a member of the large Mallow family which contains 244 genera with 4,225 known species. Well-known members of economic importance include okra, cotton, cacao and durian. There are also some genera containing familiar ornamentals, such as Alcea, Hibiscus, Malva and Lavatera, as well as the genus of trees, Tilia. Commonly called Globe Mallows, this Sphaeralcea will easily bloom for 5 months bookending the summer months.