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

Lemon-Yellow Maximilian Sunflower

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What a lively stem of pale October daisies, and so tall that I'm only able to pick some by using an eight-foot stepladder.  'Lemon Yellow's the daisy to grow when you need flowers twelve feet in the air—you never know when you, too, will have such a niche need—and you need them into October.  Everyone has that need.

 

Here's the view looking north through the 'Lemon Wave' to the two-story carriage house.  My eyes are level with its eaves. 

 

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After lugging that same stepladder to the terrace, I can see 'Lemon Yellow' waving at me from the back of the "Winter" garden bed, which is twenty feet deep and thirty wide.  ("Winter" garden?  This is a bed that's easy to see from the house year-round, so it has more than the usual number of shrubs and trees and evergreens that have even a modest presence in the cold months.) 

 

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A bit closer.  'Lemon Yellow' stems wave in the wind, a nice contrast to the variegated evergreen foliage of the standard euonymus in front of it, which looks the same—colorful but immobile—year-round.

 

helianthus-maximiliani-lemon-yellow-terrace-closer-6

 

'Lemon Yellow' is just one of my gangly group of ultra-tall Fall daisies that will debut on 'Geek' this month.  Stay tuned for 'Sheila's Sunshine' and 'Mellow Yellow'.

 

 

Here's how to grow this sky-high October daisy:

Latin Name

Helianthus maximiliani 'Lemon Yellow'

Common Name

'Lemon Yellow' Maximilian Sunflower

Family

Asteraceae, the Aster family.

What kind of plant is it?

Hardy flowering perennial.

Hardiness

Zones 4 - 9.

Habit

Unbranched very tall stems from a spreading colony of roots, with flowers up the top three-to-five feet of each stem.

Rate of Growth

Fast once established.

Size in ten years

A colony five feet wide and twelve or more feet tall.

Texture

Open and almost bamboo-like, until the bright-yellow daisies emerge in very late Summer and early Fall, spectacularly outing this plant as a daisy not a grass.

Grown for

its rarity:  Maximilian sunflowers normally have school-bus-yellow flowers.  Lemon Yellow's pale-tipped clear-yellow flowers are unique, and especially welcome when the other high-altitude daisies in your garden besides the species of H. maximiliani (e.g.: Silphium, Inula, and other Helianthus) are also likely to be school-bus yellow or, at lower altitudes, the white, pink, blue, and purple of asters and mums.

 

its foliage:  The leaves are nearly nine inches long but barely an inch wide; the leaf is folded longitudinally upward on either side of the center vein, too, making it look even narrower.  Leaves curve up, out, and down from the stems. 

 

its size and scale as a perennal:  A colony twelve feet tall and four or five feet wide at the base could (and will unless gently supported) arch outward to twelve feet and farther.  If you planted a lot of Maximilian sunflower along the south edge of a terrace, you could sit in its shade by August. 

 

its flowers: single pale-yellow daisies, about two inches across, are paler still at the petal tips, and are without even a drop of the red that, in the species, makes its flowers school-bus yellow.

Flowering season

Late Summer, early Fall: The end of September into October here in Rhode Island.

Culture

Full sun and almost any soil.

How to handle it

Maxmilian sunflower thrives in soils from heavy and poorly-drained to sharply-drained and out-and-out dry.  The plant will be shorter and more self-supporting in dry soil, which is a convenience but, then, again, doesn't provide the vertiginous and sky-scraping wonder of twelve-foot stems teetering in beds of rich soil that get plenty of water. 

 

Growing your 'Lemon Yellow' in New Mexico?  I bet it will be five to six feet tops, and a dense, sturdy, and high-octane show.  East of the Mississippi, though, eight to twelve feet or even higher is what you should expect.  In the way of so many giant perennials, the stems are self-supporting only until their thoughts turn to flowers and setting seed, when they can sway and swerve alarmingly.  Best to be pro-active:  I have a ten-foot length of rebar pounded deep into the ground at either side of my colony.  By early August the stems are getting to eight feet and then ten, so I tie twine around each rebar and then around the entire colony at about six feet, to keep the still-growing upper reaches of the stems nodding outward gracefully instead of falling over disgracefully.

 

Let the flowers mature to seeds for the birds.  I haven't noticed self-seeding at all; if it's a problem for you, then dead-head by cutting the stems off at, say, eight feet as soon as the flowers fade.

 

This is a very hardy perennial, so you can cut it to the ground—every last inch—in late Fall instead of waiting until Spring, as you would if it were only marginally hardy.  The colony doesn't need division, but if you want to pot up hunks for plant sales and friends, Spring is the time to do that.  (In general, everything that flowers in the Fall doesn't want to be transplanted or divided until Spring.) 

 

Because I'm crazy about the height of 'Lemon Yellow', I've never tried to pinch the stems back in May or June to keep it shorter.  Maximilian is supposed to be able to branch, but unpinched stems (at least for me) are straight and single their entire length.

 

Giant perennials need creative handling if they're not to look like awkward stunts.  I grow 'Lemon Yellow' at the back of a bed that's twenty feet deep and thirty feet wide.  And it's next to the vertical Magnolia 'Sun Spire', which is already sixteen feet tall and looks as if it intends on twenty, so 'Lemon Yellow' is not the tallest guy on the team by any means.  The colony is fronted by "low" stuff of six to eight feet: An evergreen euonymus grafted up to make an enormous standard, and a young PG hydrangea that's already eight feet tall.  Some day—in a decade, I'm hoping—everything will be backed by a ten-foot hedge of yew.  Its dark needles will be a sensational backdrop to the bright flowers, and its strict (again, I'm hoping) wall-like form will be a stunning counter to 'Lemon Yellow's arching informality. 

 

Given that 'Lemon Yellow' looks vaguely bamboo-like, at least before it blooms, huge late-Summer ornamental grasses (let alone true bamboos) would only be repetitive.  Instead, think tall woody shrubs with round or broad leaves (like the 'Sun Spire') or huge banana-leaved tropicals like cannas and elephant ears.

Downsides

You only get the tallest growth in the very same situations—rich soil and plenty of water—that enable the colony to flop miserably.  But staking is easy if you don't wait to do it until the flopping has already been torturing you for a couple of weeks. 

Variants

Helianthus maximiliani itself is the same scale as 'Lemon Yellow', but with boring yellow-orange flowers.  It needs the same commitment to staking.  Other stratospheric late-Summer-and-Fall-blooming daisies to consider include Helianthus verticillatus (to fourteen feet), Helianthus angustifolius (rosemary-like foliage to only seven feet, and pretty much self-supporting), Helianthus giganteus (to eight feet with boring two-inch foliage), and Helianthus grosseserratus (which, to me, is much like H. giganteus.)  All have single deep-yellow flowers, so these pale-yellow variants are prized:  H. angustifolius 'Mellow Yellow' and H. giganteus 'Sheila's Sunshine'.  

Availability

On-line.

Propagation

By division in Spring.

Native habitat

Heliopsis maximiliani is native to Eastern North America, but is happy growing in the drier and colder Rocky Mountain as well as Mediterranean-mild West Coast climates, too.

 
 
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