Allium is a group of plants that include many ornamental plants with attractive flower heads and also several well known edible plants such as garlic and onions. The ornamental alliums are of great value in the garden displaying globe flower heads in spring and early summer. They are good as cut flowers and can also be dried.
How to choose alliums
To choose the right alliums you need to consider some aspects. In terms of plant size there are alliums such as ‘Gladiator’ or Allium stipitatum ‘Mount Everest’ that can grow to 1m tall. These alliums are great to give height and shape to your border where they will absolutely play an important role.
Smaller alliums such as Allium sphaerocephalon can be planted in groups in front of borders, in rock gardens or in pots adding detail and a special interest to a specific area in the garden.
Consider that most of the alliums produce flowers in spring and early summer. They have no particular interest during a great part of the year.
Flower color varies from white and pinks to deep blues and purples. White flowering varieties goes well in the “white gardens” when combined with other pale color plants. The more vibrant ones, blues and purples, create a great impact when combined with early flowering perennials that produces orange or yellow flowers.
In terms of cultivation, what you need to consider when choosing alliums is your type of soil. If you have heavy soil with poor drainage you will need to to improve it.
When to plant alliums
The best time to plant allium bulbs is early to mid autumn.
Where to plant alliums
There are two things you absolutely need to consider when planting allium bulbs: soil drainage and sunlight.
Alliums, as most of the bulbs, need a good draining soil otherwise they can easily rot. A full sun position is the other aspect you need to provide them. If you meet these two requirements you are in good position to have great alliums in your garden.
Also, take in consideration to avoid windy positions as allium heads are heavy and can be easily destroyed. Don’t forget that alliums can also be grown in pots.
How to plant alliums
Prepare the soil removing any weeds. Plant the bulbs at a depth of about 3 to four times the bulb size. Smaller bulbs can be planted at a distance of 10cm from each other, while bigger species need at least 20-25cm in between.
Next, we will show step by step how to plant alliums in a pot. We are planting two bulbs of Allium Gladiator that produce plants to 1m high.
40 Allium sphaerocephalon bulbs which produce smaller flowers.
And a mix of 5 other allium bulbs.
We are using a big deep container with good draining holes.
Then we add some crocks over the holes and a generous layer of grit at the bottom.