Add it to your home screen and it opens full screen: no browser bars, one tap away, and everything stays signed in. Free, nothing to download from an app store.
- Tap the Share button in your browser
- Scroll down and choose “Add to Home Screen”
- Open GrowSomeFood from your home screen
- Open your browser’s menu
- Choose “Add to Home screen” or “Install app”
- Open GrowSomeFood from your home screen
Leek
The elegant, hardy allium: a long-season crop grown for its mild, tender white shank - deep-planted and hilled to blanch it, and cold-hardy enough to dig from frozen ground.
Safety notes Safe for people; like all alliums, toxic to dogs and cats in quantity. The tough dark-green leaf tops are edible but usually cooked into stock rather than eaten whole.
Overview
Leeks are the patient gardener's allium: no bulb to wait on, just a thick, tender, mild-flavored shank that takes most of a season to build but rewards you with a vegetable far more refined than onion. They're the backbone of leek-and-potato soup, and prized wherever a gentle onion flavor is wanted without the bite.
The one thing to knowFirst, the blanched white shank is the prize, and you create it by planting deep and hilling soil up the stem so the buried portion stays pale and tender.
Quick facts
- Sprouts in
- 12 daysRange: 7–16 days
- Soil temperature
- 70 °FRange: 50–77 °F
- Start indoors
- 10 weeks before transplantRange: 8–12 weeks
- Height
- 24 inRange: 12–36 in
- Spread
- 4 inRange: 3–6 in
- Cold
- Takes hard frostdamaged below 0°F
- Heat
- Struggles above 85°F
- Life cycle
- Grown as an annualBotanically a biennial
- Save seeds
- Second yearafter overwintering a few plants
- Soil
- Well-drained
- Water
- Medium
- Plant spacing
- 6 inRange: 4–8 in
When to plant
Nothing is open today. Spring transplanting opens 5 months, Mar 13 to Apr 24.
- Transplant Mar 13 – Apr 24 Opens in 145 daysAbout 4 weeks before to 2 weeks after your last frost (Apr 10 here)Spring transplants for a fall-into-winter harvest; choose overwintering varieties for standing crops.
Frost here: last around Apr 10 (Mar 27 to Apr 24 most years), first around Oct 25. Zone averages, your own yard may run a week or two either way.
Life stages
From the first start to harvest
Follow the growing sequence. Choose a stage to see its care and signs to watch for.
Stage 1 of 4 · The growing sequence
Germination
Day 0 to 12 from sowing
Care at this stage
-
Keep the mix evenly moist
Leek seed is slow, like all alliums. Start indoors 8-12 weeks before your transplant date and keep the surface damp at 65-75°F.
-
Expect grassy, looping sprouts
Seedlings emerge as a single looped thread, then straighten into a chive-like blade. Fresh seed matters - allium seed dies within a year or two.
Stages can overlap; weather, variety, and growing conditions change the pace.
Harvest
- White shank at least 1 inch thick and 6+ inches long
- Firm, upright plant with healthy blue-green fans
- No central flower stalk (harvest bolted plants first)
- Lift as needed once shanks are usable
- Overwinter hardy types with mulch
Per plant 1 leek, 4 to 16 ozPicking pull once
Cook with leeks
Watch out for
5 to know. 1 is high-risk: White Rot (Allium). None are active in October.
White Rot (Allium)Severity High DiseaseSeason: Apr–JunYellowing, wilting plants that pull up far too easily because the roots have gone, and - on the rotted bulb base - white cottony fungal growth with tiny black poppy-seed-like dots through it.
Leeks are fully susceptible where it is present. Use clean seed and plants, and avoid moving infested soil into the bed.
Yellowing, wilting plants that pull up far too easily because the roots have gone, and - on the rotted bulb base - white cottony fungal growth with tiny black poppy-seed-like dots through it.
There is no viable garden treatment. Remove and bin infected plants, never compost them, and do not grow alliums in that soil again. This is why clean planting-stock discipline matters more here than for any other allium problem.
This is entirely about never introducing it. Buy certified disease-free seed stock, sets and plants, never plant grocery-store bulbs or cloves, quarantine new stock, and do not move soil, bulbs or tools between an affected bed and a clean one. Once it is in, it is essentially permanent.
The most serious allium disease there is. A soil fungus (Sclerotium cepivorum) rots the roots and the base of the bulb, growing a white fluffy mold over it studded with tiny black sclerotia like poppy seeds. Those sclerotia survive in the soil for twenty years or more and germinate whenever an allium is planted above them, so a bed that gets it is finished for alliums within a home gardener's timescale. It arrives on infected planting stock and on moved soil.
Onion MaggotSeverity Medium PestSeason: Apr–JulIndividual plants yellowing and wilting while their neighbors look fine, and - on pulling one - small white maggots with brown, slimy rot in the bulb base, shank or stem.
The maggots work in the shank base - the part you actually eat - so an infested leek is a write-off rather than a trimming job.
Individual plants yellowing and wilting while their neighbors look fine, and - on pulling one - small white maggots with brown, slimy rot in the bulb base, shank or stem.
There is no rescue for a maggot-riddled bulb. Pull and destroy infested plants rather than composting them, and never save affected bulbs for replanting. Beneficial nematodes drenched into the soil help suppress the larvae in a bed you have to keep using.
Rotate alliums yearly, cover the crop with row fabric through the fly's spring egg-laying window, space plants out rather than growing them in dense rows, and never plant into fresh manure, which draws the flies in.
The larvae of a small gray fly - the onion fly is the same insect - that lays its eggs at the base of allium plants. The white maggots tunnel into the bulb, shank or stem base, and the damage they leave opens the door to soft rot, so the plant yellows, wilts and collapses into a mush. It is worst in cool, wet springs, in unrotated allium beds, and in dense rows where the maggots can work from one plant to the next.
Leek MothSeverity Medium PestSeason: May–SepRows of tiny holes and pale windowpane patches on leaves, tunneling into the central leaves and shank, and small cream-and-brown caterpillars or their silk cocoons on the foliage.
Rows of tiny holes and pale windowpane patches on leaves, tunneling into the central leaves and shank, and small cream-and-brown caterpillars or their silk cocoons on the foliage.
Remove and destroy infested leaves; Bt or spinosad timed to young larvae helps. Parasitoid wasps (Trichogramma) are being used as biocontrol where the moth is established.
Cover the crop with row fabric during the moth's flight periods (spring and late summer) - the single most effective defense; rotate alliums and clean up debris where pupae overwinter.
A small brown moth (Acrolepiopsis assectella) whose caterpillars mine and tunnel into leek leaves and down into the shank, causing 'shot-hole' and windowpane damage and opening the plant to rot. Now established in the northeastern US and eastern Canada, with two or three generations a year.
Rust (Allium)Severity Medium DiseaseSeason: Jun–SepOrange-red raised dots and streaks on the leaf blades, worst in humid spells and on crowded, poorly spaced or congested plantings.
Leeks are especially prone to rust, and it is the standard late-season complaint on them. Strip the worst leaves and the plants still crop, since the shank itself is rarely affected. Bandit and Tadorna are among the rust-tolerant varieties.
Orange-red raised dots and streaks on the leaf blades, worst in humid spells and on crowded, poorly spaced or congested plantings.
Strip or shear off the worst-affected leaves early and let clean growth come back, improving airflow at the same time. A bulb crop usually still matures, so harvest on schedule rather than writing it off - rust rarely reaches the bulb itself.
Give wide spacing and full sun so the leaves dry quickly, avoid overhead watering and excess nitrogen, divide congested perennial clumps, and rotate alliums on a three-year cycle. Rust-tolerant varieties are available in some allium crops.
A fungal disease that raises bright orange pustules on allium leaves. The pustules destroy green tissue, and since those leaves are what feed the bulb, a heavy infection shrinks the crop or weakens the clump. It builds in humid weather, in crowded plantings and in high-nitrogen soil, and it rarely reaches the bulb itself.
ThripsSeverity Low PestSeason: Jun–AugSilvery-white streaks and fine speckling on leaves and petals, brown discolored patches, distorted buds and blooms that fail to open properly, and tiny sliver-like insects that drop out when you shake foliage or a flower over a sheet of white paper.
Leeks tolerate moderate thrips levels without complaint. Heavy feeding through a hot dry summer reduces vigor and shows as silvery scarring down in the leaf axils.
Silvery-white streaks and fine speckling on leaves and petals, brown discolored patches, distorted buds and blooms that fail to open properly, and tiny sliver-like insects that drop out when you shake foliage or a flower over a sheet of white paper. Worst in hot, dry spells and on drought-stressed plants.
A strong water spray dislodges light infestations, and on a plant that can take it a hard shear and clean regrowth clears them outright. For heavier pressure use insecticidal soap, neem or spinosad, aimed down into the leaf sheaths and buds where thrips actually shelter, and repeat at intervals since eggs and pupae escape a single spray. Spinosad is a registered insecticide: use only a product labeled for the crop you are treating, follow the label exactly, and observe its pre-harvest interval.
Scout early, before the damage reaches the part of the plant you care about. Start with clean planting stock, keep plants well watered since drought-stressed plants suffer worst, avoid heavy nitrogen, clear weedy hosts nearby, and hang blue or yellow sticky traps to catch the first arrivals. Reflective mulch deters them, and predatory mites, lacewings and minute pirate bugs do real work outdoors.
Tiny slender sap-sucking insects that rasp at leaves, buds and petals and drink what runs out, leaving silvery-white streaking and fine flecking, brown scorched patches, and new growth that comes out twisted or fails to open. They breed fast in hot, dry weather, shelter deep in leaf sheaths, folds and unopened buds where sprays struggle to reach, and several species also transmit plant viruses - which is often more damaging than the feeding itself.
Good & bad neighbors
Plant nearby
-
The classic allium-carrot pairing: leek scent is credited with masking carrots from the carrot rust fly, and carrot scent with confusing onion/leek flies. No competition.
- Traditional pairings, thin evidence
-
Beets and leeks grow well side by side with different needs and root depths.
-
Alliums are traditionally credited with deterring cabbage moths from brassica beds.
-
Long-season row-mates with matching moisture and feeding needs; a traditional and practical pairing.
-
Often interplanted; some growers report the allium scent discourages pests around strawberries.
Varieties · 6
You pick one when you add Leek to your garden. Its days to maturity set your harvest window.
American Flag (Broad London)
The classic garden heirloom: thick, uniform shanks with blue-green flags, good flavor, and reliable cold tolerance for fall and early-winter harvest.
Variety details for American Flag (Broad London)
Medium-long white shanks topped with broad blue-green leaf fans.
heirloomstandardcold-hardyA dependable all-purpose leek.
King Richard
The fastest, most tender leek: extra-long, slender white shanks ready weeks ahead of most.
Variety details for King Richard
Very long, slim, pale shanks with light-green tops.
earlylong-shankfastIdeal for baby leeks and an early crop - but not winter-hardy, so harvest before hard freezes.
Bandit
The go-to overwintering leek: short, thick, dark blue-green plants bred to stand through hard winters for fresh digging into spring.
Variety details for Bandit
Stocky, thick shanks with very dark blue-green, frost-hardy leaves.
overwinteringcold-hardystorageResists Rust (moderate)
Slow to bolt and rust-tolerant.
Bleu de Solaize
A beautiful French heirloom whose blue-green leaves flush violet in cold - very hardy for overwintering, with thick shanks and rich flavor.
Variety details for Bleu de Solaize
Thick shanks with dramatic blue-green leaves turning purple in cold weather.
heirloomoverwinteringcold-hardyA gardener's favorite for looks and toughness.
Giant Musselburgh
A big, mild Scottish heirloom (since the 1830s): fat, tender shanks that grow to impressive size, cold-hardy and forgiving.
Variety details for Giant Musselburgh
Very thick, short white shanks with broad fan-shaped green leaves.
heirloomlargecold-hardyA great beginner leek for size and reliability.
Tadorna
A dependable fall and early-winter leek: uniform, thick, dark blue-green shanks with good standing ability and rust tolerance.
Variety details for Tadorna
Uniform medium-thick shanks with dark blue-green upright leaves.
fallcold-hardyuniformResists Rust (moderate)
A market-grower favorite that suits home gardens well.
Grower tips
Notes from growers, tagged with the zone they grow in. A person reads every post before it appears.
Nobody has posted about Leek yet. The first one usually saves someone a season.
Free account. Your post shows your grower name and zone, never your email.