How To Grow Allium or Ornamental Onion
Allium or ornamental
onions are fantastic spring blooming bulbs that more and more savvy
gardeners are tucking into their gardens. What's not to like
about these cheerful bloomers? They are bone hardy if grown in well
drained soil (sorry you clay garden folks – this is not your
plant) and given a shovel of compost in the spring. They bloom
regularly and if you control the early slugs, you are not likely to see
any problems with this plant. And you have over 500 varieties to choose
from – what could be better?
there are several different sizes of bulbs here, remember the general
guideline to plant a bulb as deep as twice its length. So if the giant
allium bulb is three inches high, then the bottom of the bulb goes six
to nine inches deep.
all time favourite of all ornamental onions is the Star of Persia or
Allium christophii. Now, sometimes this one is sold under the name of
A. albopilosum but it's the same plant. It is called the Star of Persia
because of the fantastic seed pod that looks like a multi-pointed star.
flower is a metallic purple and beautiful and if you plant the bulb out
in the full sun about four to six inches deep, this star will flower
for years in your garden. Plant them four to six inches apart
– and yes, you'll want more than one so just give
in and order at least three to grow in a clump.They'll be about twenty
four inches tall so do plant them where they will be easily seen.
Allium 'His Excellency'
truly spectacular show-stopper ornamental onion is Allium
This is truly a huge flowering bulb reaching forty
eight inches tall on the stalk and producing a massive six inch
This one is quite hardy, is never bothered by pests (unless
these pests are human or slugs) and easily grown.
Plant the bulbs four
to six inches deep in a very sunny spot.
You want full sun with this
one so the stems will stay stiff and upright.
Shade gardens will
produce weak stems that flop over and there are few sights sadder than
a flopped over allium when the flower is too heavy for the stem.
have to plant more than one of these ornamental onions, plant them at
least eight inches apart. The plant breeders are using A. giganteum to
give extra height and flower size to other hybrid bulbs. The best known
of these is the cross between Allium giganteum and Allium stipitatum
(native to Afghanistan) that is sold as 'Globemaster'. 'Globemaster'
has a ten inch, silvery-violet blossom and will be a hit in any garden.
Allium moly is a smaller species that is
well worth growing. A. moly is bright yellow and about ten inches tall.
It begins blooming at the end of May to early June in local gardens and
if planted in the full sun and 3 inches deep, it will live happily in
your garden for years.
Allium moly 'Jeaninne'
In fact, if happy it will not only live where
you plant it, it will live just about anywhere you don't want to weed
it out of. (which accounts for why I haven't grown it before in my
This is a bit of a spreader so do plan on weeding it out after
a few years (I am). If you can find the cultivar 'Jeannine' purchase
this because it has two flowering stems on each stalk rather than the
single of the species. You'll get twice the blooms and twice the seeds.
This native of Southern Europe should be planted four inches apart.
Plant about six in a small clump to get you started - after that move
them around your garden or allow them to self sow to give a cheerful
yellow show after the tulips are finishing.
for hot and dry
Allium neapolitanum is a
cheerful little bulb producing glistening star-shaped flowers held on
15 inch stems (give or take a few inches). The nodding buds open up to
upward facing, glistening white flowers with yellow anthers. This is a
bulb of the dry, open sunny spaces in Portugal and the Mediterranean.
Do not put it in clay soils and do not grow it where it will get much
summer moisture. Moist soils in the summer will simply kill it; it
wants full, hot sun and baking, well-drained soils with no clay. While
the flowers have a pleasant fragrance to them, as a native of southern
climates, they can be a bit miffy in colder climates. Many gardeners do
find however that they make excellent forcing bulbs.
The last, but not least, is Allium
karataviense. This strapped-leaf shaped plant is well worth a place of
honour in any rock garden or the front of a sunny perennial border. At
eight inches tall, the four to six inch blossom is a bit unexpected but
quite welcome in the early spring garden. There are a range of
available colours - from pinks through violets - so grow them all.
Plant these Alliums or ornamental onions three inches deep and three
inches apart (you'll want lots of these) to give you a great show in
the spring. If you've never grown them before, you'll be surprised by
the almost lack of flower stem - the flower looks as if it were resting
directly on the leaves.
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