Download Alliums All Season Long

Alliums All Season Long
Deer resistant and dynamic, these bulbs provide color from the first showers
of spring to the last leaves of fall
by Stephanie Cohen
Fine Gardening issue 127
‘Jeannine’ golden onion, Allium moly‘Jeannine’
Photo/Illustration:
David Cavagnaro
Alliums are often overlooked as one of the best bulbs for constant color throughout the
seasons. Part of the problem is their common name: ornamental onion, which conjures up
images of supermarket onions in shades of lime green or red. Alliums actually come in oval,
spherical, or globular flower shapes, blooming in magnificent colors atop tall stems.
Because good perennial-garden designs are often made up of contrasting shapes, alliums’
rounded blooms make them great components for interesting garden combinations (not to
mention that deer generally avoid them—to escape onion breath). Pair them with spikes or
other large-leaved perennials to hide any decaying foliage.
It’s easy to think of alliums simply as colorful summer plants, but these easy-to-grow bulbs
have options that will keep the blooms coming right up to the first frost. You’ll find
outstanding choices here that will make you reconsider alliums as your new seasonal
companions.
ORNAMENTAL ONIONS
Allium spp. and cvs.
Hardiness: Alliums can be grown in Zones 3 to 9, depending upon the species and cultivar.
Alliums aren’t too picky: In most cases, alliums grow in average garden soil and need full
sun and good drainage. The drainage is critical because so many of the bulbs are huge and
will rot with too much moisture.
Aside from that, they are easy to grow and come back year after year with almost no
maintenance. Occasionally, they need dividing after a few years, when you start to notice a
decrease in flower production (usually this pertains to those with small bulbs). One of the
best things about alliums is that most animals, especially deer, find the taste unappealing
and won’t nibble on the leaves.
Plant them in fall: Alliums go in while leaves are falling. Average planting depth should be
about three times the diameter of the bulb. I have planted alliums late in fall right up to
Thanksgiving. Just be sure the ground hasn’t frozen yet so that the bulbs have time to take
root.
Video: How to Plant Alliums
SPRING IS FOR MORE THAN JUST DAFFODILS AND TULIPS
Giant onion, Allium giganteum
Photo/Illustration:
Jennifer Benner
In late spring, ‘Jeannine’ golden onion (USDA Hardiness Zones 3–9) emerges, growing a
scant foot tall. It has two stems of individual, star-shaped, golden yellow flowers forming a
circular floret. I love ‘Jeannine’ for the ease with which its soft, straplike, blue-green leaves
tuck between the wonderful blue flowers of late spring to early summer. To get any kind of
display, plant at least a dozen bulbs. ‘Jeannine’ multiplies continuously and, in a few years,
will put on quite a show. If you love large drifts of golden daffodils, you will be equally
impressed with this small golden treasure.
After viewing this average-size garden gem, moving on to something that looks like a giant
lollipop on a stick is a shocker. Giant onion (Zones 5–9) is all that its name implies,
peeking out in late spring and growing up tall and bold. The 4-inch-diameter flower is a
pretty shade of lilac, but the large leaves are troublesome, turning yellow even before full
flowering is complete. If this plant is not placed in the back of a border, it will need a hardy
perennial to cover its dying foliage. Giant onion’s flowers are long blooming and are
excellent to use as cut flowers. When planting, leave plenty of room for these large bulbs to
grow.
Turkestan onion, Allium karataviense
Photo/Illustration:
Bill Johnson
In late spring, the short, squat Turkestan onion (Zones 5–9) flowers. This is my kind of
plant, standing a mere 1 foot tall. The thick leaves on this onion are a showy gray-green
mottled with shades of purple and a sort of reddish edge. The long-blooming flower is a pale
silver-lavender. Even after flowering, do not remove the spent flower because it dries well.
During a previous year, I spray-painted one to make a fairy wand for my daughter’s
Halloween costume. For those who dare to be different, try spray painting them in your
garden; it creates a funky effect. Plant Turkestan onion in groups of three or five for
maximum impact. It looks great with ‘Caradonna’ blue sage (Salvia nemorosa‘Caradonna’,
Zones 5–9) in the background—a dramatic combo.
A handsome plant that has been grown since Victorian times is tumbleweed onion (Zones
4–9). The flowers are rose purple and begin to form on short stems. The infertile flowers
shoot out, giving the effect of fireworks. Tumbleweed onion has an open, airy look rather
than a compact head. The leaves go fast after flowering, but the seed head will look good
for a while. It will eventually drop off and begin to roll around the garden, just like a
tumbleweed in the Old West.
Tumbleweed onion, Allium schubertii
Photo/Illustration:
Courtesy of Dutch Gardens
WATERWISE BULBS KEEP SUMMER ROLLING
Nodding onion, Allium cernuum
Photo/Illustration:
David Cavagnaro
Summer-flowering alliums display quite a bit of diversity. Nodding onion (Zones 4–8) is a
northeastern native bulb. Light pink and dainty, it gets its common name because its flowers
hang down. Nodding onion starts flowering in early summer and has a long bloom period.
Because this allium stands only 18 inches tall, it easily tucks in between spring- and
summer-flowering perennials. For those who have never grown this bulb, be aware that it
always nods. This does not mean it needs water.
One of the colors that people love in perennial borders is blue. Blue globe onion (Zones 4–
10) is an exceptional combination of dark and light blues melded together. The spherelike
flowers reach 24 inches tall and work well for cut arrangements. Pair this variety with
‘Becky’ Shasta daisy (Leucanthemum × superbum‘Becky’, Zones 5–8) or ‘Silver Moon’
Stokes’ aster (Stokesia laevis‘Silver Moon’, Zones 5–9), both of which have daisylike white
flowers that are a great color contrast. This bulb loves to grow hot and dry, so avoid
sprinkler systems that keep the soil moist.
Blue globe onion, Allium caeruleum, syn. A. azureum
Photo/Illustration:
Steve Aitken
Stars of Persia, Allium cristophii, syn. A. albopilosum
Photo/Illustration:
Michelle Gervais
Another allium with the wow factor is stars of Persia (Zones 5–8). It has a 10-inch-diameter
globe of striking light amethyst with silver shadings and green eyes. It is a large bulb, so
leave space to optimize its full potential. The leaves are covered with white hairs—hence,
it’s other common name: downy onion. It’s a great dried flower, but don’t plant it in the front
of the border, unless deteriorating foliage turns you on. It’s tall and needs full sun, so place
it behind any plant 10 inches or shorter.
ROUND OUT THE GROWING SEASON WITH THESE COLORFUL
ODDBALLS
Black onion, Allium nigrum, syn. A. multibulbosum
Photo/Illustration:
Susan A. Roth
Drumstick allium, Allium sphaerocephalon
Photo/Illustration:
Michelle Gervais
One of my favorite summer bulbs is black onion (Zones 5–8). The star-shaped flowers are
white, but the centers are dark black to dark green, providing great contrast. Some
designers don’t like the often-washed-out appearance of white flowers, but the black
centers of this allium are strong enough that even picky gardeners will like it. Its striking 4to 6-inch-diameter flowers bloom for several weeks, but even afterward, the seed heads
look fine for a while (for those of you nondeadheading enthusiasts). Pair this with some of
the chocolate-colored heucheras (Heuchera spp. and cvs., Zones 3–8) or any other darkleaved plant for some subtle color echoing.
Drumstick allium (Zones 4–9)—I assume “drumstick” refers to a drumstick on a chicken
rather than the kind used to play drums—is a great summer favorite of mine. I love this eggshaped flower, which tends to naturalize in my garden. When other full-sun flowers fade,
this beauty maintains its hot color. The crimson-purple flowers are very compact. Because
they flower in midsummer, when golden daisies are rampant, you have an easy, no-fail
combo. I like the extended bloom time of about three to four weeks, but once again, the
foliage begins to turn yellow while the flowers still look great.
‘Hair’ allium, Allium‘Hair’
Photo/Illustration:
Bill Johnson
Circle onion, Allium senescensssp. glaucum
Photo/Illustration:
Bill Johnson
If you haven’t seen ‘Hair’ allium (Zones 4–8), it looks like it put its roots in an electric
socket. Each stem produces several thin, tentacle-like green flowers from a purple base.
Pair ‘Hair’ with anything that you think is rather boring because this bulb will catch your
attention (even if you are not partial to such a weird plant).
Circle onion (Zones 4–9) is a very cool plant. The blue-green leaves give a corkscrew
effect—hence, its nickname. Circle onion’s flower is a deeper pink than the species and,
with its showier foliage, is more desirable. Try it in rock gardens or the front of the border;
the curly onion looks most dramatic in Japanese-style gardens.
‘Ozawa’ Japanese onion, Allium thunbergii‘Ozawa’
Photo/Illustration:
Jennifer Brown
Read more: http://www.finegardening.com/alliums-all-season-long#ixzz45Bf0YRPO
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