Louis Raymond experiments in his own gardens like

a mad scientist, searching out plants that most people have

never seen before & figuring out how to make them perform.- The Boston Globe

…Louis Raymond ensures that trees can grow in Brooklyn…

or just about any other place where concrete consumes

the dirt and skyscrapers shield the sunshine.- USA Today

 
 

NEW Trips to Take!

Myrtle's easy when the conditions are right.

 
 
 
 

NEW Plants to Try!

Louis tries to capture the exact words to describe the fleeting but deep pleasures to be found in these Summer-into-Autumn incredibles.

 
 
 
 

New Gardening to Do!

Allergic to bees? You can still have an exciting garden, full of flowers and color and wildlife.

 
 
 
 

Plant Profiles

Thread-leaved Helianthus

helianthus-angustifolius-mellow-yellow-flower-640

 

Demure daisies in front of the frankly-fabulous purple foliage of cannas.  The weeks before frost are some of the most exciting of the year.  'Mellow Yellow' daisies are stylish, indeed, with icy-yellow petals that are only buttery at the base. 

 

The dark centers of the flowers echo the dark canna leaves, but pair just as handsomely with the shady recesses in the bright-yellow foliage of Chamaecyparis 'Fernspray Gold' planted at the other side of the colony.

 

helianthus-angustifolius-mellow-yellow-flower-cham-640

 

These congenial and stylish flowers are the October thrill of 'Mellow Yellow', but the plant is just as exciting before bloom, May through September, thanks to its thread-leaf foliage and strong straight stems.

 

helianthus-angustifolius-mellow-yellow-foliage-640

 

Back-lit in the picture above, they are as bright as the 'Fernspray Gold' foliage, and a ferny contrast to the white-veined leaves of Forsythia 'Kumson' at the front.  These three are doing the close harmony of a country-music girl group:  All the notes are in the same chord, and everyone's flawlessly on pitch. 

 

Looking through the colony from the other side, the huge leaves and thick stems of the purple cannas are the ultimate in contrast.  This purple canna still keeps some green at the center of its leaves; it's the only note of harmony amid all the bombast. 

 

helianthus-angustifolius-mellow-yellow-canna-640

 

The canna's flowers are the color of discord, though.  I thought I'd planted my 'Russian Red' cannas, whose small "species" canna flowers are (despite the name) a softer tomato bisque.  And anyway, 'Russian Red' is eight to ten feet tall, so the flowers would be out of view. 

 

But what I'd planted instead—see below—were 'Wyoming' cannas, with large "hybrid" flowers in bright orange.  Worse, 'Wyoming' only gets five to six feet tall, so its flowers are jangling right there with those of 'Mellow Yellow'. 

 

helianthus-angustifolius-mellow-yellow-overall-640

 

'Wyoming' isn't mellow at all.  Yuck.  Next year, 'Russian Red' will return, and 'Wyoming' will get planted where it belongs, in the Red Gardens.

.

 

Here's how to grow this elegant and easy all-season daisy:


Latin Name

Helianthus angustifolius 'Mellow Yellow'

Common Name

'Mellow Yellow' helianthus

Family

Asteraeae, the Aster family.

What kind of plant is it

Flowering perennial.

Hardiness

Zones 6 - 9

Habit

Clumping and amazingly upright.

Rate of Growth

Fast.

Size in ten years

Eight to ten feet tall and five feet across.

Texture

Thrillingly delicate, especially for a perennial this size.  Only Helianthus salicifolius provides an equal—although differently arrayed—volume of thread-leaf excitement.

Grown for

its foliage.  The leaves are as long as seven inches, but only a quarter-inch wide at the most.  They arise from tall and unusually self-supporting stems, each leaf a third of the way around the stem from the previous.   

 

its flowers.  'Mellow Yellow' flowers are conspicuously mild in hue compared to the school-bus yellow of the straight species: a butter-and-sugar that even those who eschew yellow can enjoy.

 

its ease.  Helianthus angustifolius succeeds a wide range of soils and exposures; see "Culture" below. 

 

its popularity with wildlife.  H. angustifolius attracts both birds and butterflies.

Flowering season

Late: Stems bud-up excitingly in late September, and start into bloom in mid-October.  My colony is in fully bloom as I write, this first week of November.

Culture

Good soil, full sun or light shade, with anything from average water to loads of water; tolerant of seasonal flooding as well as salt spray.  Not tolerant, though, of brackish water.

How to handle it

Helianthus angustifolius is refreshingly easy and reliable.  My source assured me that the plant would grow to six feet tall the first season of planting, as well as bloom heavily.  It did.   

 

As with all the late-season daisies, the exceptional height is at once a temptation and a caution.  You'll inevitably need to provide some support if you want the plant to grow as tall as possible, but it's never very successful to try righting a colony after it's started to sprawl.  Instead, put in six-foot pea stakes in August, while the colony is still as flawlessly upright as in my picture above, and discretely tie around the colony with twine near the top of the stakes.  If you have backed the colony with a much taller (and sturdier) plant or structure or hedge, you can also anchor the colony to it even higher.  The stems are strong, so if you've tied around the whole colony with twine at about five feet, and you then tie a couple of the individual stems to the higher support at the back, you may have handled everything.

 

As exciting and exceptional as the tall height of 'Mellow Yellow' is, there's no question that it's easier to cut the entire colony down by half in June.  The stems branch very generously, and flower from every stem-tip, so the overall amount of bloom is, if anything, increased.  But the colony never achieves the full height it would if it hadn't been cut back.

 

The colony can be divided in early Spring, which is fortunate in that, with such tasteful flowers and delicate foliage, many friends and visitors will also want to grow it.  As with my own experience, replanted sections will grow people-high and bloom beautifully by October. 

Downsides

Gardeners below Zone 6 will want to grow 'Mellow Yellow', too.  One experiment would be to grow it in rich soil that has excellent drainage—on a slope or a mound—and to mulch heavily.  Or, because the plant establishes so readily in Spring, you could dig up the colony (or at least convenient portions of it) in the Fall, pot them up and then overwinter them dormant in your basement, replanting them outside in early Spring.  For such exceptional foliage and flowers, why not?

Variants

Helianthus angustifolius itself is as exciting in habit and in foliage as 'Mellow Yellow', although the flowers themselves won't add a new element to your Fall garden: Deep yellow daisies are the norm for all the sky-high daisies, and not all the species provide the option of paler-yellow cultivars.  If you grow a lot of tall daisies, then, school-bus yellow will be in good supply.

 

Even so, there are many Helianthus species to consider, both annual and perennial, with heights from a foot to almost fifteen feet.  Helianthus annuus is the annual sunflower, with flowers in the widest range of color and size, from deepest burgundy to near white, and from four- or five-inch daisies to heavy huge disks a foot across and more. 

 

I'm exploring all the tallest Helianthus species, let alone other stratospheric daisies.  Members of this stepladder-friendly group of perennials appear regularly here on 'Geek'.   

Availability

On-line and at retailers.

Propagation

By division of the clump in early Spring.

Native habitat

Helianthus species are all native to North and South America.  H. angustifolius is broadly native to the Eastern United States; 'Mellow Yellow' was discovered near Covington, Louisiana .

 
 
FacebookTwitterRSS Feed

Stay in touch!

 

Sign up for twice-monthly eNews, plus notification of new posts:

 

* indicates required