Description
The type species of the genus is Allium sativum which common garlic, and the genus also contains onions and other related vegetables. Now widely cultivated species include Allium cristophii and Allium giganteum which are grown for their spherical flower heads that are borne on the end of long and strong stems. The spheres are made up of many small star shaped flowers and have a beautiful architectural quality.
Key Facts
- Common Name(s):Round-headed Leek
- Hardiness:Fully hardy
- How big will I get? Allium sphaerocephalon can grow to a height of 1m and a spread of 0.5m.
- Did You Know That:If grown in soil with no sulphur present at all, all Allium species will lose all their typical scent?
Plant Calendar
A rough guide to how this plant will change through the year.
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| J | F | M | A | M | J | J | A | S | O | N | D |
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Care Guide
Soil Requirements
Allium sphaerocephalon is a versatile plant and can cope with wet or drier soils, but prefers there to be decent drainage. This plant can grow in soil with a wide range of pH levels, it is not picky about the pH level of the soil.
Best Position
Allium sphaerocephalon prefers a sheltered position and requires full sun to thrive, this consists of more than six hours of direct sunshine per day.
Maintenance
Allium sphaerocephalon is fairly low maintenance and doesn’t require any pruning. Alliums are often kept untouched through Autumn and Winter due to the attractive shape of their seed head which is reminiscent of the flowers just without the colour. Any remaining growth can be cut back in early Spring to encourage fresh growth or immediately after flowering if you are wanting more space in your borders.
Pest, Diseases and Wildlife
Allium sphaerocephalon is generally pest free, it can be vulnerable to certain diseases such as downy mildew. It is also known to attract bees, butterflies and other pollinators. It is toxic to cats, dogs and horses.
