Allium hollandicum 'Purple Sensation'
You can find this plant throughout the garden but it is a major wow factor in the Hot Garden where it is planted en masse to harmonise with drifts of blue/purple Salvia x sylvestris 'Mainacht' AGM, contrast with yellow Euphorbia Excalibur ('Froeup') (PBR) AGM and interspersed with accents of deep purple Sambucus nigra f. porphyrophylla 'Eva' (PBR). The balls of intense purple flowers bob about in the breeze on long stalks above the other plants looking so perfect they look unreal. They are loved by gardeners and visitors alike and we would not be without them.
Vital statistics
- Common name
- Dutch garlic 'Purple Sensation'
- Family
- Alliaceae
- Height & spread
- 1m (3ft) x 7cm (3in)
- Form
- Bulbous perennial.
- Soil
- Fertile, well-drained soil.
- Aspect
- Full sun.
- Hardiness
- Fully hardy but may be tender when young.
Allium
The name Allium is from the ancient name for garlic, which is part of the genus. There are estimated to be around 700 species within the genus, and many cultivars. There are perennials and biennials, ranging in height from 10-150cm (4in- 5ft) or more.
They are mainly from dry and mountainous areas, all from the northern hemisphere, and they have adapted to live in almost every plant habitat on the planet, from ice cold tundra to burning, arid deserts.
They have upright to spreading linear-shaped leaves. The flowers are bell, star or cup-shaped, borne in spherical umbels 1-10cm (1/2in-4in) across.
In most species, a single bulb produces clusters of offset bulbs around it, which gradually form clumps.
Taller species look good in groups in a border. The flower heads dry well.
Several species have culinary uses, including A. sativum (garlic), culinary onions, shallots and chives. Many members of the genus give themselves away with the distinctive smell of onions when the bulb or foliage is bruised.
The whole group was prized by the ancients as possessing medical and aphrodisiac qualities as well as flavour. The Romans are sometimes held responsible for their wide distribution by taking them wherever they went.
Allium hollandicum 'Purple Sensation'
This bulbous perennial has long, strap-shaped, grey-green basal leaves 30-60cm (12in-24in) long. In early summer it bears umbels 8cm (3in) across of 50 or more star-shaped, deep violet flowers. Remove immature seed heads to prevent paler-flowered self-sown seedlings.
Flower stalks dry well and can be used in arrangements or they can be left outside to provide winter interest as they look good covered in frost.
Contact with bulbs may irritate skin.
Cultivation
- Grow in fertile, well-drained soil in full sun. Plant bulbs 5-10cm (2-4in) deep in autumn.
- Plant clump-forming species with rhizomes at, or just below, the soil surface in spring.
- Alliums are susceptible to white rot, downy mildew and onion fly.
Propagation
- Propagate by offsets, removed when dormant. Keep moist and well ventilated, and dry progressively as foliage dies back.
- Seed can be sown in spring at about 13°C (55°F) but plants may not come true to the parent.
- Divide clumps of spring flowering species in summer.
AGM
The RHS Herbaceous Plant Committee awarded Allium hollandicum 'Purple Sensation' an Award of Garden Merit and described it as a:
'Bulbous herbaceous perennial to 90cm, with short basal leaves dying down by flowering time. Flowers small, vivid rosy-purple, in crowded spherical umbels. Attractive seed heads.'