Thursday, July 2, 2009

Ornamental Allium - Fireworks In The Summer Garden

Ornamental onions and garlic are from the genus Allium (AL-lee-um). Allium is classified in family Alliaceae although some classifications have included it in the lily family (Liliaceae). With about 1250 species, it is one of the largest plant genera in the world. These perennial bulbous plants produce chemical compounds that give them a characteristic onion or garlic taste and odor. Many are used as food plants. Ornamental allium has its origins in Central Asia and the Mediterranean area.

When I was growing up, our neighbors planted rows of ornamental Allium along the fence that divided our yards. Every spring we could see glimpses of these flowering fireworks through the chain link fence. We had no lack of bees and butterflies that these perennials attracted.

Allium has shiny, glossy foliage and produces 12" - 48" high leafless stalks upon which sit tufted globes of color. The late spring and early summer blooms typically have great potential for cut flower production. The blooms last much longer in a vase than your typical flower. This plant attracts bees, butterflies and birds, but disinterests deer and rodents. It doesn't have any pest problems. The dried flower heads can provide winter visual interest.

Before you plant this carefree item let's go over the basics. Allium has average water needs so it will need regular watering but it doesn't swim. Allium is very heat tolerant, but if it wilts it's in trouble. It requires sun to partial shade, like full p.m. sun. In general, Allium is hardy in USDA Hardiness Zones 3 -10. Only in zones 3 and 4 do they require mulch to get through the winter. If you plant them in containers where the bulbs are more exposed, just bring them in so they're not outside below 10°F. I haven't heard of Allium being unable to grow in any pH soil types.

When you plant Allium in the fall you must focus on the variety and the size of the bulb to ensure it is spaced correctly. With those details in mind, choose a site that receives proper sun exposure and where the soil drains well. Prepare a hole three times the circumference of your bulb. Therefore, a 2" bulb should be planted 6" deep, a 3" bulb planted 9" deep, etc... If planting a group of bulbs, space the holes 4" to 12" apart depending upon the varieties' sizes. Position the bulb in the hole with the pointed end up and cover it with the soil. After soaking it in, you may spread mulch over the entire planting area if you'd like. Compost or wood chips also work well. Synthetic fertilizer should not come into contact with the bulbs because it will burn them. Similarly, fertilizer placed on the soil just above the bulbs will cause damage.

Deadhead flowers to encourage more blooms unless you want the seeds or wish to dry them to use in dried flower arrangements. Although ornamental alliums are edible I wouldn't eat them. Just enjoy their beauty.

With nearly 400 ornamental allium species to choose from, it's easy to find one that fits into any garden. These sun-loving flowers look like cheerful lollipops bouncing in the wind, or fireworks displays in the garden. I've listed my favorites (the best ones) below.

A. aflatunense: Produces purple flowers in May and that last two to three weeks. Plants are 24" - 36" inches tall with large, multi-flowered umbels. Planting them 3" apart, or nine per square foot. Full sunlight to PM only sunlight. Only those of you in Zone 3 will need to mulch.

A. christophii: Also known as the Star of Persia. As the bootstrap leaves wither, A. christophii sends up stout stems topped by 8" -10" airy amethyst spherical heads that are almost too big and too beautiful to be real. If you plant them in a group surrounded by leafy long lasting green foliage of another perennial, passersby will have to stop to look. Blooms June and is hardy to Zone 4.

A. caeruleum: These 12" to 24" high plants produce vivid blue multi-flowered umbels that look stunning in front of a white picket fence or white siding. It flowers in May or June and blooms last two to three weeks. The bulbs usually aren't big and can be planted 2" apart with 15 - 25 bulbs per square foot. Hardy in Zone 4 with mulch, Zones 5 to 7 hardy without mulch. Zone 3 misses out. Full sunlight only.

A. giganteum: A spectacular beauty of lilac-purple flowers on 3' to 4' tall stalks. Flowers in June and July and blooms for up to three weeks. It is native to the Himalayas. These giant 6" - 9" flower-heads open green, then turn deep violet. Easy to grow and very heat-tolerant. Plant them 12" apart or one bulb per sq. ft. in full sunlight to PM only sunlight. USDA Climate Zone 3 with mulch, Zones 4 to 7 without mulch.

A. x Gladiator: Another fantastic one with 4" to 5" bluish-purple globe shaped flowers. Blooms in summer on strong 36" to 48" stems in full sun, well drained soil and with minimal water. A great cut flower. Grow happily in Zones 4 - 8. They are dramatic planted at the back of the border behind lower growing perennials.

A. aflatunense Globemaster: Can't wait to have fluffy 8" violet poofballs in your garden? Plant in fall 3" apart to have flowers in late spring that last two to three weeks. Plants are 24" - 36" tall with large, multi-flowered umbels. Full sunlight to PM only sunlight. Climatic Zone 3 with mulch, Zones 4 to 7 without mulch. Because it's sterile, it puts all its energy into producing more flowers instead of making seeds - and you enjoy the difference! Ideal combined with low-growing, mounding perennials.

A. sphaerocephalon Hair: For something unique and fun, plant 'Hair'. With its free-form style and bright green color, is a bold addition to any garden.

A karataviense: It has wide, blue-green leaves and short flower stalks with golf ball-sized spheres of white, pale pink or pink. Flowers in May and lasts 2-3 weeks. Plants are 10" - 12" tall and have sweetly scented florets. Plant them 6" - 12" apart. Mulch if you live in Climatic Zone 3 and Zones 4 to 7 without mulch. Full sunlight to PM only sunlight.

A. karataviense Ivory Queen: Broad blue-gray foliage shows off the blooms to beautiful effect. Only 6" to 9" inches tall, the plants have masses of fragrant six inch white florets in early summer. Full sun or partial shade. Because they're small they're good for pots in Zone 3 but don't need mulch in Zones 4 - 8.

A. moly: Yellow flowers appear in spring and lasts 2 - 3 weeks. Plants are 10" - 12" tall with a loose sphere of yellow flowers that have a slight garlic fragrance. They're actually native to Southern Europe. Plant A. moly 2" - 3" inches apart with mulch in Zone 3. Hardy through Zone 4-7. Full sunlight to PM only sunlight and can be grown in dry shade.

A. x Mount Everest: Plant the mountain's majesty in your yard against a dark background. It will highlight the five inch snowy white orbs on their 36" tall stems. Desired by gardeners, butterflies and bees. ‘Mt. Everest's’ long strapping leaves last until flowering time. Blooms May – June. Hardy to zone 4.

A. neapolitanum: Plants are 15" tall with a loose bunch of bright white flowers and last two to three weeks. They like to be about 4"apart. Climatic Zone 7 with mulch and Zones 8 to 10 without mulch. Full sunlight only.

A. oreophilum: Synonymous with A. ostrowskianum, A. oreophilum flowers in spring and also lasts 2 - 3 weeks. Plants are 10" - 12" inches tall with a loose 5" head of red flowers. Climatic Zone 3 with mulch, 4 to 7 without mulch. Planting density: 2" - 3" inches apart. Full sunlight to PM only sunlight.

A. aflatunense Purple Sensation: As the name suggests you'll get deep purple flowers on this May bloomer that will last 3 weeks. Plants are 24" - 36" tall with 3" flowerheads. But no worries, each head has up to 50 blooms! Punctuate your garden with purple! Planting density: 3" apart even in dry, hot soil. Easily self-sows. Full sunlight to PM only sunlight. Climatic Zone 3 with mulch, Zones 4 to 7 without mulch.

A. schubertii: The lilac-pink blooms on these bloomstems are irregular in length and truly look like fireworks, unlike other Allium which have a solid ball of color. Up to 200 miniature star-styled flowers shoot out in all different lengths from the flower's center. And they're famously fragrant. Blooms May – June. Pedicels grow 12" - 18". Give A. schubertii full sun and well-drained, even dry, soil. Plant the large bulbs 4" deep and about 8" apart. Hardy to Zone 5.

A. siculum: Synonymous with A. bulgaricum and Nectaroscordum siculum. A treasured favorite for more than 300 years in southern France. Just the thing for the water-saving garden, this carefree Allium shoots up 2-1/2' to 3' tall and crowns itself with a dozen or more blooms. These full sun flowers are unusual with their green-white base and heavy maroon markings. The large bloom clusters arch and cascade down and out for a great visual effect. Requiring very little summer moisture and grows heartily in Zones 4 - 9.

A. sphaerocephalon: Also known as Drumsticks, this is an eye and bee-catching wonder from its crimson-purple 2 inch wide blooms all the way down to its narrow grassy leaves. Blooms later than most Allium from July–August. Hardy to Zone 5, it gets about 24" to 30" tall.

Need to save water? Plant Allium. Want a carefree plant? Plant Allium. Want color, height and compliments? Plant Allium.

Purchase these bulbs now while quantities last to plant in this Autumn's garden! Next year this time you'll be enjoying nature's fireworks. You'll definitely want a full display.

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1 comment:

Janet, The Queen of Seaford said...

Great list of Allium to plan a bed with constant blooms.