Growing leeks in 3 seasons: summer, autumn and winter 15 growing tips

The quality of home-grown leeks from your own soil with plenty of compost, organic matter, and humus is like comparing the Champions League to amateur football class D. The same thing, yet incomparable. You can prepare young leeks like asparagus, fried in sizzling butter. The tasty white shafts of mature leeks can be delicious stewed, and the blue-green part of the leek plant adds flavor to any vegetable broth or soup. Growing leeks is easy. You can sow leeks at intervals from January to April and harvest leek plants from late August through the winter until February.

Like most other vegetables, you harvest better, more beautiful leeks in a sunny position with soil packed with organic matter, compost, and humus. Follow the various basic principles of growing leeks here.

In this blog, I will show you step by step how to set up a small fruit row: from preparing the soil and planting the bushes to caring for and, of course, harvesting in the summer.

📹 Extra fun: I have added videos in which you can watch the setup, planting, and harvest.

You can grow leeks in three different crops: summer, autumn, and winter leeks. Pre-growing young leek plants from seed takes 80-90 days for all crops. For a good cultivation schedule, it is important to know that the growth duration after planting varies enormously.

Summer leeks are ready in 80 to 100 days, autumn leeks take 80-180 days and are suitable for late autumn, and winter leeks remain in your vegetable garden for about 180-300 days.

Autumn and winter leeks can be harvested until the end of winter. If you sowed and planted late, it may be that your leeks are still too small before winter. No worries, after the winter the leeks will continue to grow, and you will have winter leeks very early in the season.

Leeks can be pre-sowed in a tray under glass, which is especially useful for early cultivation.

Leeks are closely related to the onion family (allium) and let's admit it, the smell of a freshly cut leek... does indeed resemble an onion. And sometimes when you clean leeks, you get emotional and tears come to your eyes.

Leeks usually only flower in the second year, but under certain conditions, the plant can bolt and flower in the first year. This happens more often due to a lack of nutrients, good soil structure, or water. It is important to avoid those three deficiencies for a good harvest.

Here is a brief summary of the nutritional values in 100 grams of leeks:

• 130 kilojoules
• 2 g protein
• 0.3 g fat
• 5 g carbohydrates
• 250 mg potassium
• 5 mg sodium
• 60 mg calcium
• 1 mg iron
• 30 mg phosphorus

The levels of vitamins and nutrients vary enormously between the white and green parts of the leek, with the most vitamins found in the green parts. So don't throw them away in the kitchen, but process them into a hearty soup. Hmmm, delicious to drink when you take a break in the vegetable garden. You'll be ready to go again right away.

The varieties can be classified into summer leeks, with a light green leaf color, a relatively long white shaft, and a soft texture. This makes them quick to use, as summer leeks do not handle autumn weather very well. Examples include Swiss Giants and Bulgarian Giants. The latter should be eaten immediately because it deteriorates quickly in the autumn. Bulgarian Giants are in some cases slightly more susceptible to viruses, but they are less sensitive to thrips.

Tip: Like other leafy crops, leeks are often included in crop rotation with, for example, cabbage or celery. This helps keep the soil healthy and optimizes yield.

In general, autumn giant types are primarily used and recommended. Autumn leeks have a fairly short to moderately long shaft, and the leaf is broad, gray-green, and thick. The autumn type is the Blue-Green Autumn; these also have an upright leaf posture and are less sensitive to diseases.

Finally, there is the winter leek, with dark gray-green leaves that are not too broad. It has a moderately thick and short shaft, but possesses good winter hardiness. For winter leeks, it is best to use the Blue-Green winter because this variety is well-resistant to cold.

The soil must be loose, meaning good access to air and moisture-retentive. Leeks require deeply loosened soil; a compacted layer is always undesirable. 65% of leek roots are in the top 25 cm, 25% in the 25-50 cm layer, and 10% deeper than 50 cm. Sandy soil is also fine for leeks, provided it can retain sufficient moisture. In sandy soil, you can get by with a broadfork; in heavier soil, you may choose to dig deeply if you are so inclined. Heavy clay soil can always be lightened with 2 kg of lava grit per m², which you work in well.

The ideal pH for leeks is between 5.8 and 6.8, with a humus percentage of 5% to 8%. Leeks can grow well in all types of soil, but they prefer loose, moisture-retentive soil.

Leeks prefer soil with "old strength." This is soil rich in organic matter where leek growth is possible even without new fertilization. Nitrogen then becomes available through the breakdown of the organic matter already present in the soil. You achieve this by sowing a green manure crop in the year preceding the leek cultivation. Alternatively, you can also apply a layer of rich compost in the autumn to the bed where you will be growing leeks the following year.

Leeks love well-fertilized soil with plenty of organic matter. If you have access to cow manure in the autumn, you can apply about 1 wheelbarrow of stable manure per 15 m2 before winter. Uncomposted organic material should always be worked into the soil well in advance. Leeks do not grow as well if uncomposted stable manure or many plant residues are added to the soil in the spring. If you do not have stable manure available, you can also purchase compost via the Plukkers webshop.

If the leeks start to look light in color, an additional nitrogen-containing fertilizer should be added; blood meal is excellent for this. Leeks also appreciate being fertilized a little extra several times during growth. This is especially important in sandy soil. If you have wood ash available, you can also sprinkle this over the soil before planting and work it in. Leeks like some extra potassium. You can also use Vinasse potash if you don't have clean wood ash available.

Three sowing periods can be distinguished. Like other crops, leeks can be sown in different ways. In early January, indoors in warmth, summer leeks are sown (grow lights are useful here to raise them well). You can use a deep root tray with 45 cells of 9 cm deep for this to separate the seeds and easily move the young plants later. It is also possible to raise leeks in a pot indoors, which is especially useful if you have limited space. Thin sowing is important so that young plants have enough room to germinate. Keep the seedbed weed-free for better leek growth. In March, outdoors under cold frames or tunnels, you sow for autumn leeks and in April outdoors for winter leeks. Note that leeks need at least eight hours of bright sunlight per day for good growth.

Summer leeks are planted out in March when they are 3 to 4 mm thick. The other (autumn and winter) leeks are planted 13 weeks after sowing (+/- 90 days, see earlier in this article). The plants should be approximately 6 mm thick by then. Every week of deviation from the 13 weeks costs about 5% in yield! The seed requirement is about 3 grams of seed per m2.

Leeks have high demands regarding water management! A few days of waterlogging already results in clearly poorer leeks, and drought is not good either. Leeks need 380-400 mm of water over the entire growing period. Watering is therefore usually necessary. If leeks only get 220 mm, the yield will almost halve! At more than 400 mm, the yield decreases again. Therefore, using a simple rain gauge is important to keep an eye on rainfall volumes. 1 mm less water results in 20 grams less leek per m2. Give 10 mm (10 liters of water per m²) immediately after planting, or pour 100 ml per dibble hole into the holes. If you don't have an abundance of water in your vegetable garden, opt for dibble holes with a leek planter instead of planting by hand.

Irrigation should be well distributed over the entire period; do not give a lot of water once and then stop for a while. You should definitely not wait until the soil is dry. There is a simple test. You can tell when to water in sandy soil when the soil still feels slightly moist at a depth of 25 cm. That is the depth where most of your roots are. With loamy or clay soil, you should still be able to knead 'sausages'. After September, you don't need to water anymore.

Tip! The first 2 mm when watering evaporates immediately and is of no use. It is best to give between 10 and 15 mm of water at a time in small drops. In planting holes, that is 100 to 150 ml; if you are watering the entire surface, that is 10 to 15 liters per square meter.

A system that sets you up for success regarding watering is an irrigation system with soaker hoses or drip hoses. In this article, you can read how you can easily install one.

Earthing up leeks means mounding soil from beside the planted leek rows up to the base of your leeks. Many say this gives you longer white shafts on your leeks. But earthing up leeks is also strongly discouraged by many seasoned vegetable gardeners. By creating a ridge where your leeks stand, a lot of soil ends up between the leaves of your leek. Many growers in the vegetable garden also tell me that while shafts do get longer with earthing up, they also become less thick. So, your gain in height is lost in the thickness of your leek.

The truth likely lies somewhere in the middle, and I am convinced that whether you earth up or not, you can always grow beautiful leeks with the instructions in this article. I will not be earthing up this year; I suffer a lot from the leek moth and leaf miner, so the less I have to lift my insect netting, the better.

Harvesting leeks, loosen your soil before pulling

Leeks grow best if you take crop rotation into account in your vegetable garden. This means that you put leeks in a different place every year so that the soil does not become depleted and diseases have less chance to build up. Because leeks are a biennial plant, they can bolt in the second year if you leave them standing, which you prefer to avoid. Prevent leeks from bolting by sowing the right varieties and planting at the right time. By applying crop rotation, you ensure that the leek grows optimally every season and that the soil structure remains healthy. It also prevents pests and fungi from settling in the soil and striking again the following year. Good crop rotation of 4 to 5 years for members of the Allium family also helps in controlling pests. Therefore, ensure that leeks only return to the same spot after at least two years. This way, you get the best results from your soil and your leeks remain strong and healthy.

So, you plant leeks in the cabbage bed of the previous year, and after leeks, you can grow fruit crops such as zucchini, pumpkin, or artichokes. Read more here about crop rotation in the vegetable garden:

In 2017, I filmed my summer leek crop from seed to harvest. You can see what happens during the different stages of cultivation. But like every gardener, I learned quite a bit that I would definitely do differently this year.

Harvesting leeks requires the right moment and a careful approach. Once the stems have reached a good thickness and length, usually around 20 cm long and from 2 cm (summer leeks) up to 6 cm (winter leeks) thick, it is time to harvest.

Preferably use a garden fork to lift the leeks from the ground. Insert the garden fork next to the leek and push gently so you don't damage the roots. In loose soil, you can often simply pull the leeks out by hand, which is called 'pulling from the ground,' while in firm soil you use a garden fork to loosen the plant before removing it. Pull the leek out slowly, taking care to keep the long white stem intact. By using this technique, the leek remains firm and you can process it immediately in the kitchen. Try to harvest when the soil is dry so that less earth sticks to the roots, making the leeks easier to clean. This ensures the best result and keeps the quality of your leeks optimal.

Depending on the harvest time and your goals, there are several ways to store leeks. Since your home-grown leeks usually come fresh from the field, it is worth storing them smartly so you can enjoy them for as long as possible.

• In the refrigerator: fresh leeks will keep for 1 to 2 weeks in the vegetable crisper. Wrap them loosely in a damp cloth or store them in a perforated plastic bag to prevent drying out.
• In a cellar or box with sand: traditionally, leeks can be 'heeled in' upright in slightly damp sandboxes or soil in a cool, dark room (0–5 °C). This keeps them fresh for several weeks to months while retaining their flavor.

Freezing:

• Wash and cut the leeks into rings or pieces.
• Blanch briefly (boil for 2–3 minutes and then cool quickly in ice water).
• Drain well and pack into freezer bags or containers.
• Shelf life: 8–12 months.

Drying: use a dehydrator or a low temperature in the oven. Dried leeks are great for later use in soups or stews.

Fermenting: just like sauerkraut, you can ferment leeks with salt and herbs. This gives a tangy flavor and allows them to be kept for months in Mason jars.

Winter-hardy varieties can simply be left in the ground until you need them. Leeks are quite frost-resistant (sometimes down to -10 °C), although covering them with straw or garden fleece is useful during severe frost. In this way, you are basically using the ground as a natural refrigerator.

Hopefully, you are fully motivated to pop those leek seeds into the ground. I am certainly starting soon, and I hope you do the same. If you find the information in this article valuable, please share it with your friends and acquaintances. Who knows, they might catch the gardening bug too.

You can give the site a boost if you decide to purchase your gardening supplies in our webshop. Good luck with your leek cultivation and see you next time.