When to sow leeks?
- Botanical name
- Allium ampeloprasum
- Family
- Amaryllidaceae
Leeks are sown outdoors from March to June, 1.5 cm deep. They germinate in 20 to 25 days. They are harvested from August to March.
Leeks are biennial plants. The edible parts are the bulbs, leaves and flowers.
Leeks through the year
- indoor sowing
- transplanting
- outdoor sowing
- harvest
In short
The last frost is not on the same day everywhere, so the recorded weeks are a guide and not a date.
Growing conditions
Companions in the bed
Companion planting is tradition and not an agronomic claim. What is recorded is which pairs sources recommend and which they advise against.
Next to cucumbers the neighbours go to the edge of the bed.
- “Cited” means the pair is named by one source or two.
Pests and diseases
Listed here is every problem for which the sources name this plant as a host. The problems are not listed in order of how common they are.
White rot of alliums
disease- Signs
- Growth is stunted and the leaves yellow and die. Pulled up, the underground part is coated in a white to grey mould or crust holding thousands of tiny black fruiting bodies.
- Prevention
- Plant only stock confirmed healthy. Pull out infected plants and take them away, not onto the compost. The fruiting bodies stay in the soil for years, so do not plant alliums in an infected bed for four to five years. Rotation on its own does not wipe the disease out.
- What to do
- For the home garden there is no product. The measure is the bed: remove the infected plants, work compost into the soil and leave a long break without alliums.
Keep track of your plants with Tendask
Log the task and set a reminder for the next one. Every plant keeps its own history, so there is nothing to guess at.
Related plants
The plants below are in the same botanical family (Amaryllidaceae).
Sources about the plant: ASPCA Toxic and Non-Toxic Plants, Bayerische Landesanstalt für Weinbau und Gartenbau, GBIF Backbone Taxonomy, KGZS Kmetijsko gozdarska zbornica Slovenije, KGZS Zavod Ljubljana, KGZS Zavod Nova Gorica, NC State Extension Plant Toolbox, Royal Horticultural Society, Semenarna Ljubljana, Smernice za strokovno utemeljeno gnojenje (Mihelič et al., MKGP 2011), University of California Agriculture and Natural Resources, Utah State University Extension, Wikidata. Checked between 14 and 28 August 2026. The problem descriptions also draw on: EPPO Global Database, University of Maryland Extension.