Growing guide
How to grow leeks in Ireland
Leeks make a useful standing larder when summer beds have finished. A couple of timed plantings can supply autumn and winter meals without lifting the whole crop at once. The challenge is patience during the slow seedling stage. Transplanting is a manageable beginner method because directly sown final rows need more weed control and careful watering.
On this page
At a glance
- Start with
- Seed raised in modules or a nursery bed, or young transplants
- Best position
- Moisture-retentive, workable ground prepared with compost or manure
When and where to start
Indoor sowing. Early crops are sown in January or early February; the main crop in March; late crops in late April or early May. Seedlings often need eight to twelve weeks to reach planting size.
Direct sowing. An outdoor nursery bed can be sown in April. Direct sowing into final positions is possible, but adds weed and irrigation demands.
Planting out. Early crops go out in April, main crops in May or June, and late crops from late June into July. Aim for sturdy plants around 15–25 cm tall; adjust to their development and soil conditions.
Planting and spacing
For single plants, use 30 cm rows with 15 cm between plants, or 20 × 20 cm. For modules containing several seedlings, plant the cell intact at 30 × 30 cm rather than separating it.
For single bare-root plants, make holes around 15–18 cm deep. Drop a plant into each and water to settle soil around the roots; let the holes fill gradually. This works only when soil is suitably moist, not saturated or very dry.
Alternatively use a trowel to plant 10–15 cm deep. Deep planting excludes light from the lower shank, producing the pale section valued in cooking.
Routine care
Water after planting in dry weather and during later dry spells. Leeks bulk up substantially in autumn, so a winter crop still needs attention during establishment.
Long-held seedlings may need nourishment rather than remaining in exhausted compost. If a longer white shank is wanted, earth up established plants carefully, keeping soil out from between the leaves.
What to watch for
Rust can slow growth without necessarily killing the crop; varieties differ in susceptibility. Note recurring problems when choosing the following year’s seed.
Bolting limits the late season. How long a plant stays useful depends on variety and weather, not a guaranteed final date. Check leaves and stems rather than judging health only by size.
Harvest and storage
Early plantings can be ready from July; later ones supply autumn, winter and potentially spring. Loosen the soil to lift only what you need.
Established leeks can remain in the ground for months where conditions permit. Consider severe frost and access to the bed. Use lifted leeks promptly; winter-standing plants reduce the need for a large kitchen stock.
Common questions
Why plant leeks so deeply?
Excluding light whitens the lower shank and gives a milder section.
Should multi-sown modules be split?
No. Plant the group intact and use the wider spacing between groups.
Must all leeks be lifted in autumn?
No. Sound established plants can stand for later picking, subject to local weather and their eventual flowering.