Potatoes Nicola

Planting: Potatoes need a light, deep, and rich soil. Choose a sunny location. Add well-rotted compost in the previous autumn by scratching it 5 cm (2in) deep after loosening the soil. Planting takes place under shelter in February-March for early varieties. For other varieties, plant them from mid-March to May, depending on the climate. Wait until the soil is at least 10°C (50°F). The flowering of the lilac is often a landmark for starting the planting. Plant several varieties in your vegetable garden to vary the crops!

Loosen the soil deeply and form rows 10 cm (4in) deep, spaced 70 cm (28in) apart. Place the tubers, sprout facing upwards, every 40 cm (16in) (or 30 cm (12in) for early varieties). Cover with fine soil when the plants reach 15 cm (6in), hill up by bringing fine soil to the base of the stems, up to 20 cm (8in) in height. Hilling up will promote tuber formation and water drainage. You can hill them up again a month later. Mulch around the plants with thin successive layers of mixed grass clippings, if possible, with dead leaves. This protection, which keeps the soil moist, also limits weed growth.

Potato cultivation does not require watering, except in case of hot weather. In this case, water the base without wetting the foliage to prevent the appearance of fungal diseases.

Diseases and pests: Potatoes are susceptible, just like tomatoes, to late blight. This is a fungal disease caused by the Phytophthora infestans fungus. Late blight develops in warm and humid weather. Small spots appear, white on the underside of the leaves and brown on the top. As a preventive measure, here are some tips to limit the risk of late blight:

• do not grow several plants from the Solanaceae family (potatoes, tomatoes, aubergines, peppers, chilli peppers, etc.) in neighbouring rows, as they are susceptible to the same diseases

• in terms of crop rotation, wait four years before growing another Solanaceae plant in the exact location

• space the plants, both within and between rows, to promote air circulation and prevent rapid disease spread

• if you need to water, do not wet the foliage

• spray a fungicide or use preparations such as horsetail decoction or garlic purée

The Colorado potato beetle, an insect of the order Coleoptera, can also hinder harvesting. You will recognise it by its yellow head and its yellow and black striped body. The best solution, although time-consuming, is to remove them as they appear. As a preventive measure, sow blue flax seeds between your rows of potatoes. Sow from April to June in shallow furrows. In addition to being repellent to Colorado potato beetles, flax will brighten up your vegetable garden with its pretty little blue flowers. You can also interplant peas between your rows of potatoes.

Other planting methods: The detailed planting method above is the most common. Different methods exist, such as mulch planting and tower planting.

Mulch planting involves placing the tubers on the soil and covering them with mulch. This protection is added as the plant grows, with the tubers always kept away from light.

Tower or container planting is practical for small spaces but requires regular watering. The tower can be built from various materials (wood, wire mesh, bags, tyres, etc.). The tubers are placed on a layer of potting soil or compost. As the plant grows, it is covered with more potting soil, leaving only the top leaves exposed, and so on until the top of the tower, allowing the tubers to form throughout the height of the container. Harvesting is done when the foliage has withered.