AlliumAllium

Allium

Allium

1. ornamental onion
2. onion
3. onion genus
4. onions

1. ornamental onion
2. onion
3. onion genus
4. onions

1. Allium

1. Tracheophyta
2. Liliopsida

Amaryllis family

1. bulbs
2. leaves
3. flowers

Leek (Allium) is a versatile and robust plant, valued in many cuisines worldwide. With its mild, oniony flavor and health benefits, it is an asset to any garden and diet. From sowing to harvest, leeks are relatively easy to care for and forgive minor mistakes.

1. TaskHarvesting

   Label

   Harvest winter leeks

   Prioritymedium

   Months

   1. 1

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Harvest only the required amount to leave the plant in the bed.

2. TaskProtection

   Label

   Frost protection for overwintering plants

   Prioritylow

   Months

   1. 1

   ConditionSevere frost expected

   Estimated effortlow

   Notes

   Cover with brushwood or fleece.

1. TaskHarvesting

   Label

   Harvest winter leeks

   Prioritymedium

   Months

   1. 2

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Harvest only the required amount to leave the plant in the bed.

2. TaskSoil preparation

   Label

   Loosen soil

   Prioritylow

   Months

   1. 2

   ConditionSoil is workable

   Estimated effortmedium

   Notes

   If not already done, prepare the soil for the upcoming season.

1. TaskSoil preparation

   Label

   Prepare soil for sowing

   Priorityhigh

   Months

   1. 3

   ConditionSoil is workable

   Estimated effortmedium

   Notes

   Loosen soil deeply, incorporate compost.

2. TaskSowing

   Label

   Sow leeks (open ground)

   Priorityhigh

   Months

   1. 3

   ConditionSoil temperature suitable

   Estimated effortmedium

   Notes

   Early varieties for an earlier harvest.

3. TaskHarvesting

   Label

   Harvest winter leeks

   Prioritymedium

   Months

   1. 3

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Last harvest of late winter leek varieties.

1. TaskSowing

   Label

   Sow leeks (open ground)

   Priorityhigh

   Months

   1. 4

   ConditionSoil is workable

   Estimated effortmedium

   Notes

   Continue sowing for summer and autumn harvest.

2. TaskPlanting out

   Label

   Plant out young plants

   Priorityhigh

   Months

   1. 4

   ConditionPlants have 4-5 true leaves

   Estimated effortmedium

   Notes

   Plant pre-grown plants into the open ground, pay attention to spacing.

3. TaskWeeding

   Label

   Weed

   Prioritymedium

   Months

   1. 4

   ConditionWeeds are visible

   Estimated effortmedium

   Notes

   Keep young plants and sowings free of weeds.

1. TaskSowing

   Label

   Sow leeks (open ground)

   Prioritymedium

   Months

   1. 5

   ConditionSoil is workable

   Estimated effortmedium

   Notes

   Late sowing for a late harvest.

2. TaskPlanting out

   Label

   Plant out young plants

   Priorityhigh

   Months

   1. 5

   ConditionPlants have 4-5 true leaves

   Estimated effortmedium

   Notes

   Plant pre-grown plants into the open ground.

3. TaskCultivation

   Label

   Loosen soil and water

   Prioritymedium

   Months

   1. 5

   ConditionDry weather

   Estimated effortmedium

   Notes

   Hoe regularly and water well during dry periods.

1. TaskSowing

   Label

   Sow leeks (open ground)

   Prioritylow

   Months

   1. 6

   ConditionSoil is workable

   Estimated effortmedium

   Notes

   Very late sowing for a late harvest.

2. TaskPlanting out

   Label

   Plant out young plants

   Priorityhigh

   Months

   1. 6

   ConditionPlants have 4-5 true leaves

   Estimated effortmedium

   Notes

   Plant pre-grown plants into the open ground.

3. TaskCultivation

   Label

   Hill up for blanching

   Prioritymedium

   Months

   1. 6

   ConditionPlants are growing well

   Estimated effortmedium

   Notes

   Earth up around the stems to lengthen the white shaft.

1. TaskHarvesting

   Label

   Harvest summer leeks

   Priorityhigh

   Months

   1. 7

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Start harvesting early summer leek varieties.

2. TaskCultivation

   Label

   Hill up for blanching

   Prioritymedium

   Months

   1. 7

   ConditionPlants are growing well

   Estimated effortmedium

   Notes

   Continue hilling up for better blanching.

3. TaskNutrition

   Label

   Fertilize

   Prioritymedium

   Months

   1. 7

   ConditionPlants are growing

   Estimated effortlow

   Notes

   Liquid fertilizer or compost tea to promote growth.

1. TaskHarvesting

   Label

   Harvest summer leeks

   Priorityhigh

   Months

   1. 8

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Main harvest time for summer leek varieties.

2. TaskCultivation

   Label

   Hill up for blanching

   Prioritymedium

   Months

   1. 8

   ConditionPlants are growing well

   Estimated effortmedium

   Notes

   Continue hilling up for better blanching.

3. TaskSowing

   Label

   Sow leeks (late varieties)

   Prioritymedium

   Months

   1. 8

   ConditionSoil is workable

   Estimated effortmedium

   Notes

   Sow varieties intended for autumn and winter harvest.

1. TaskHarvesting

   Label

   Harvest leeks

   Priorityhigh

   Months

   1. 9

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Harvest summer and early autumn leek varieties.

2. TaskCultivation

   Label

   Hill up for blanching

   Prioritymedium

   Months

   1. 9

   ConditionPlants are growing well

   Estimated effortmedium

   Notes

   Continue hilling up for better blanching.

1. TaskHarvesting

   Label

   Harvest autumn leeks

   Priorityhigh

   Months

   1. 10

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Main harvest time for autumn leek varieties.

2. TaskCultivation

   Label

   Hill up for blanching

   Prioritymedium

   Months

   1. 10

   ConditionPlants are growing well

   Estimated effortmedium

   Notes

   Last opportunity to hill up before winter.

3. TaskStorage

   Label

   Prepare leeks for storage

   Prioritymedium

   Months

   1. 10

   ConditionHarvested leeks

   Estimated effortlow

   Notes

   Store leeks cool and dark, e.g., in sand or damp sawdust.

1. TaskHarvesting

   Label

   Harvest leeks

   Priorityhigh

   Months

   1. 11

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Harvest autumn and early winter varieties.

2. TaskCultivation

   Label

   Hill up for blanching

   Prioritymedium

   Months

   1. 11

   ConditionPlants are growing well

   Estimated effortmedium

   Notes

   Last opportunity to hill up before winter.

1. TaskHarvesting

   Label

   Harvest winter leeks

   Priorityhigh

   Months

   1. 12

   ConditionPlants are mature

   Estimated effortlow

   Notes

   Harvest winter leek varieties, depending on the weather.

2. TaskProtection

   Label

   Frost protection for overwintering plants

   Prioritylow

   Months

   1. 12

   ConditionSevere frost expected

   Estimated effortlow

   Notes

   Cover with brushwood or fleece.

Sunny to partial shade

Sheltered

A sunny location promotes growth, but leeks also tolerate partial shade. Protection from strong winds is beneficial.

Deep, loose, humus-rich, nutrient-rich

Well-drained, no waterlogging

Prefers deep, loose soils well-supplied with nutrients. Avoid waterlogging at all costs.

High, consistent

Directly at the base, avoiding wetting the foliage

The soil should be kept consistently moist, especially during dry periods. Avoid waterlogging.

1. Compost

2. Well-rotted manure

3. Organic slow-release fertilizer

4. Liquid fertilizer (during the growing season)

Before planting/sowing, during the growing season

Leeks are heavy feeders and require sufficient nutrients, especially nitrogen for leaf growth and potassium for bulb formation. Good base fertilization with compost or manure is recommended.

Leeks can be grown well in mixed culture with carrots, celery, tomatoes, and strawberries. Do not plant next to legumes or cabbage.

1. Legumes
2. Root vegetables
3. Leafy greens

1. Other Alliums (onions, garlic)
2. Cabbage family

A crop rotation of at least three years is important to prevent the spread of diseases and pests, especially leek moth and leek rust. For white rot, an even longer break (8-10 years) is necessary.

1. Insects (Leek Moth, Onion Fly, Leek Miner, Thrips)

1. Fungal diseases (Leek Rust, Downy Mildew, White Rot)

1. Adherence to a wide crop rotation (at least 3-4 years, 8-10 years for white rot).
2. Use of insect netting during the flight periods of leek moth and leek miner.
3. Selection of resistant or tolerant varieties.
4. Ensuring good soil hygiene and removal of infested plant debris.
5. Optimal plant spacing for good air circulation.
6. Consistent water and nutrient supply to strengthen plants.
7. Companion planting with suitable partners (e.g., carrots).

Pay attention to early signs of pests or diseases. Regular inspection of leaves (top and bottom) and the stem base is crucial. Consider weather conditions and the planting history of the bed.

1. Sluglauchmotte

   Severityhigh

   Conditions

   1. Warm, dry periods
   2. Multiple generations per year

   Affected parts

   1. Leaves
   2. Stem

   Prevention

   1. Insect netting
   2. Crop rotation
   3. Remove infested debris

   Organic control

   1. Promote beneficial insects (parasitic wasps)
   2. Pheromone traps
2. Slugzwiebelfliege

   Severitymedium

   Conditions

   1. Moist soils
   2. Spring and late summer

   Affected parts

   1. Roots
   2. Stem base

   Prevention

   1. Insect netting
   2. Crop rotation
   3. Companion planting with carrots

   Organic control

   1. Remove infested plants
   2. Nematodes (against larvae)
3. Sluglauchminierfliege

   Severityhigh

   Conditions

   1. Flight periods in spring and late summer

   Affected parts

   1. Leaves

   Prevention

   1. Insect netting
   2. Adjusted sowing/planting times

   Organic control

   1. Remove infested leaves
4. Sluglauchrost

   Severitymedium

   Conditions

   1. Humid weather
   2. High air humidity

   Affected parts

   1. Leaves

   Prevention

   1. Resistant varieties
   2. Good air circulation
   3. Crop rotation

   Organic control

   1. Remove affected leaves
   2. Plant strengtheners (e.g., horsetail tea)
5. Slugfalscher_mehltau

   Severityhigh

   Conditions

   1. Cool, humid weather
   2. Leaf wetness

   Affected parts

   1. Leaves

   Prevention

   1. Resistant varieties
   2. Good air circulation
   3. Crop rotation
   4. Avoid leaf wetness

   Organic control

   1. Remove infected plant debris
   2. Plant strengtheners
6. Slugweissfaeule

   Severityhigh

   Conditions

   1. Moist, heavy soils
   2. Soil-borne fungus

   Affected parts

   1. Roots
   2. Stem base

   Prevention

   1. Long crop rotation (8-10 years)
   2. Soil hygiene
   3. Healthy planting material

   Organic control

   1. Dispose of infected plants (do not compost!)
   2. Soil improvement
7. Slugschossen

   Severitymedium

   Conditions

   1. Extreme temperature fluctuations
   2. Drought stress

   Affected parts

   1. Stem

   Prevention

   1. Bolt-resistant varieties
   2. Consistent watering

   Organic control

   1. Early harvest

1. Symptom

   Tunnels in leaves and stems

   Possible causes

   1. lauchmotte
   2. lauchminierfliege

   First checks

   1. Check for larvae or pupae inside tunnels.
   2. Note the type of tunnels (straight vs. zigzag).
2. Symptom

   Wilting and yellowing of leaves, rotting base

   Possible causes

   1. zwiebelfliege
   2. weissfaeule
   3. stickstoffmangel

   First checks

   1. Check plant base for larvae or white fungal growth.
   2. Check soil moisture and fertilization.
3. Symptom

   Orange-brown pustules on leaves

   Possible causes

   1. lauchrost

   First checks

   1. Check humidity and air circulation.
   2. Verify plant spacing.
4. Symptom

   Yellowish spots on leaves, greyish-purple mold

   Possible causes

   1. falscher_mehltau

   First checks

   1. Check weather conditions (cool, humid).
   2. Examine the underside of leaves closely.
5. Symptom

   Leaves pale green to yellowish, stunted growth

   Possible causes

   1. stickstoffmangel

   First checks

   1. Check fertilization history.
   2. Consider soil analysis.
6. Symptom

   Leaf margins yellow and die back

   Possible causes

   1. kaliummangel

   First checks

   1. Check fertilizer for potassium content.
7. Symptom

   Purplish leaves, poor root growth

   Possible causes

   1. phosphormangel

   First checks

   1. Check soil temperature and moisture.
8. Symptom

   Flower stalk formation in the center of the plant

   Possible causes

   1. schossen

   First checks

   1. Check weather history (cold snaps).
   2. Verify variety for bolt resistance.

1. Germination
2. Seedling development
3. Vegetative growth (shaft formation)
4. Bolting (flower stalk formation)
5. Flowering
6. Seed maturation

Leek is a biennial plant that forms the edible shaft in its first year and flowers and produces seeds in its second year. For harvest, leeks are picked before bolting, as the stem becomes woody afterwards.

June - August (in the second year)

White to pink-purple

Umbellate flower clusters

Leeks flower in the second year after sowing. The flowers are attractive to bees and other insects.

1. July
2. August
3. September
4. October
5. November
6. December
7. January
8. February
9. March
10. April

Year-round, depending on variety and sowing time

Carefully pull the plant from the soil or loosen with a digging fork and remove.

Harvesting can take place from summer until the following spring, depending on the variety and sowing time. Winter-hardy varieties can remain in the bed over winter and be harvested as needed. Harvest before the plants bolt, otherwise the stem will become woody.

As needed, once the desired size is reached.

1. Shaft has reached desired diameter (approx. 2-5 cm)
2. Leaves are vigorous green and upright
3. Before a flower stalk forms (bolting)

Remove soil from harvested leeks, trim outer, damaged, or very green leaves. Shorten roots. Wash thoroughly, especially between leaf layers, to remove soil.

1. Overwinter in the ground (winter-hardy varieties)
2. Cool and moist in sand or damp sawdust
3. Refrigerator (short-term)
4. Freezing (processed)

Winter-hardy leek varieties can remain in the ground all winter and be harvested as needed, as long as the soil is not frozen. For cellar storage, a moist environment is important to prevent drying out.

Cool and moist

In the ground: several months; in sand/sawdust: 2-3 months; in refrigerator: 1-2 weeks; frozen: up to 12 months

1. Freezing (blanched or raw)
2. Drying (for soup greens)
3. Pickling (rarely)

1. Fresh consumption
2. Cooking
3. Freezing

1. Drying (as a spice or soup greens)

Leek is a versatile vegetable that can be used raw or cooked. It makes an excellent base for soups, stews, and sauces.

Mild oniony, slightly sweet, earthy

1. Soups and stews (as a base or main ingredient)
2. Gratins and casseroles
3. Vegetable side dish (steamed, fried)
4. Quiches and tarts
5. Raw in salads (especially young, tender shafts)
6. Stir-fries

1. Wash leeks thoroughly, as soil can accumulate between the leaf layers.
2. Use the white and light green parts of the shaft; the dark green part is often tougher but can be used for broths.
3. Slice into rounds, rings, or strips.

1. Potatoes
2. Cheese
3. Cream
4. Bacon
5. Fish
6. Poultry

1. Shaft (white and light green)
2. Leaves (tender, green parts)
3. Flowers (as edible garnish)

1. Roots
2. Very tough, outer leaves
3. Woody flower stalk after bolting

Leek is non-toxic to humans and has been used as food for centuries. Like other Allium species, it can be toxic to pets (especially dogs and cats) in large quantities.

Yes, especially young and tender leek shafts can be used raw in salads or as a garnish. They have a fresh, mild-spicy flavor.

Biennial (flowering and seed production in the second year)

Open-pollinated, insect-pollinated

To obtain true-to-type seeds, sufficient isolation distance from other flowering leek or onion species (Allium genus) is required, as they can easily cross-pollinate. For home gardeners, a distance of 800 meters or staggered flowering times may be sufficient.

1. Flower heads dry out and turn brown
2. Seed capsules open easily
3. Seeds are black and hard

Cut off flower heads when the first seeds are ripe, and allow to dry further in a dry, well-ventilated place. Shake or rub seeds from the capsules.

Separate seeds from chaff and plant debris by winnowing and sieving.

Cool, dry, and dark in airtight containers.

At least 20-50 plants for good genetic diversity.

Not common, as insect pollination is efficient. If necessary, flowers can be pollinated with a fine brush and then isolated with a net.

Select only healthy plants for seed production. Watch for signs of fungal diseases (e.g., leek rust) and remove affected plants. Maintain good crop rotation.

For seed saving, it is important not to harvest the plants in the first year, but to leave them in the ground over winter so they can flower in the second year. Light winter protection can be helpful in harsh climates.

Leek is not a woody plant, so these details are not applicable.

Leek flowers provide a food source for bees and other pollinators. However, the plant itself offers little shelter or food for other wildlife.

In spring, leeks are sown in the open ground or started as pre-cultivation. Pay attention to the correct soil temperature and protect young plants from late frosts if necessary.

Summer is the main growth phase. Regular watering, hoeing, and hilling up are important for developing a long, white stem. The first summer varieties can be harvested.

Autumn is the main harvest time for many leek varieties. Hilling up can continue to promote blanching. Winter-hardy varieties can remain in the bed.

Winter-hardy leek varieties can be harvested directly from the garden bed when the soil is not frozen. Light winter protection may be beneficial.