Fresh green kale leaves with frost in a winter kitchen garden

Kale

Learn how to grow kale successfully with proper seeding and care techniques so you can enjoy nutritious green leaves in the winter.

Kale is a traditional Dutch winter vegetable that grows excellently in the cool, humid climate of the Netherlands. By sowing on time, fertilizing the soil well and weeding regularly, you will develop sturdy plants with fresh green leaves. After a few cold nights the taste becomes milder and sweeter, ideal for stews or stir-fries. With a little attention and planning, you can enjoy a healthy, winter-hardy harvest for months.

Preparation and cultivation

Sowing and soil preparation

Sow kale directly in the open ground or in a seed tray from mid-May to the end of June. Choose a sunny spot with nutritious, well-drained clay or loam soil. Work compost or well-decomposed manure into the top layer in advance to make the soil airy and rich in nutrients. Keep the soil moist but not wet so that the seeds can germinate evenly. After emergence, thin out the seedlings into sturdy plants with sufficient space to grow.

Prick out and harden off

When the young plants have four to six leaves, you can transplant them to separate pots or plant them out immediately. Give them a few days to get used to outdoor conditions by putting them outside during the day and bringing them in at night. This hardening off prevents growth stress and makes the plants stronger against wind and temperature fluctuations. Make sure the root ball remains moist and only plant out on cloudy days or in the evening to avoid burning.

Planting out and early care

Plant the kale at a distance of about 50 centimeters, so that each plant receives sufficient light and air. Press the soil firmly around the roots and water immediately. In the first weeks, regular weeding is important to avoid competition with weeds. A mulch of straw or compost helps retain moisture and keeps soil temperatures stable. Check for snails and caterpillars and remove them manually to limit damage to young leaves.

Planting and care

Plant out in open ground

Place the young kale plants outside in June or July as soon as they are sturdy enough and the risk of night frost has passed. Choose a sunny spot with nutritious, well-drained soil. Plant them about 50 centimeters apart so that the leaves have enough space to grow. Press the soil well around the roots and water immediately. A mulch of straw or compost helps retain moisture and limits weed growth, which promotes the plants' starts.

Care during growth

Keep the soil moist but not soggy, especially during dry periods. Water regularly at the base of the plant to prevent mold on the leaves. Remove weeds in a timely manner so that the kale does not have to compete for nutrients. Check for caterpillars and aphids weekly and remove them by hand or rinse with water. Light fertilization in mid-summer stimulates new leaf growth and keeps the plants vital.

Protection and maintenance in autumn

When the days get shorter and temperatures drop, kale becomes stronger and more flavorful. Protect the plants from strong winds with a low edge or net and remove damaged leaves to prevent mold. Feel free to leave the plants outside, because light frost improves the taste. Check for snails regularly and remove them manually. By keeping the soil loose and removing fallen leaves, the crop remains healthy well into the winter.

Harvest and store

When to harvest kale

Kale is ready to harvest when the leaves are firm and dark green, usually from November to February. Preferably wait until after a few night frosts, because the cold makes the taste softer and sweeter. Harvest from the bottom up by cutting off the outer leaves so that the plant can continue to grow. Use a sharp knife and avoid damaging the trunk. This way you can pick fresh kale several times a season without the plant becoming exhausted.

Store kale and keep it fresh

After harvesting, kale can be stored in the refrigerator for several days, wrapped in a damp cloth or in an open plastic bag. Freezing is ideal for longer storage: blanch the leaves briefly in boiling water, cool them quickly and freeze them in portions. This way the vegetable retains its colour, taste and nutritional value. You can also dry or ferment kale for a different taste experience. Always store in a cool, dark place to prevent spoilage.

Tips for a longer harvest period

To enjoy kale for longer, you can protect the plants in winter with fleece cloth or a low tunnel. This prevents frost damage in severe cold and keeps the leaves tender. Harvest regularly, but always leave the heart of the plant intact so that new leaves continue to grow. In mild winters you can cut fresh kale until March. By cleverly spreading different varieties and planting times you can significantly extend the harvest period.