Potatoes Tresor

Planting: Potatoes need a light, deep and rich soil. Choose a sunny location. Add well-rotted compost in the previous autumn, by scratching it into the soil to a depth of 5 cm (2in), after loosening the soil. Planting takes place under cover 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. Install several varieties in your vegetable garden to vary the pleasures!

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

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

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

• Do not grow several plants of the Solanaceae family, such as potatoes, tomatoes, eggplants, peppers, chillies, on neighboring rows, as they are susceptible to the same diseases.
• In terms of rotation, wait 4 years before growing another Solanaceae plant in the same location.
• Space the plants, both in the row and between rows, to promote air circulation and prevent rapid disease spread.
• If you need to water, do not wet the foliage.
• Spray Bordeaux mixture or preparations such as horsetail decoction or garlic purée.

The harvest can also be affected by the Colorado potato beetle, an insect of the order Coleoptera. You will recognize it by its yellow head and its yellow and black striped body. The best solution, although a bit 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 its repellent effect against 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. Other methods exist, such as mulch planting and tower planting.

Mulch planting involves placing the tubers on the ground and covering them with a layer of mulch. This protection will be added as the plant grows, with the tubers always being kept away from the light.

Tower planting or bag planting is practical for small spaces but requires regular watering. The tower can be constructed from various materials (wood, wire mesh, bag, tires). The tubers are placed on a bed of potting soil or compost. As soon as the plant grows, it is covered with potting soil, leaving only the topmost leaves exposed, and so on until the top of the tower, allowing the tubers to form along the height of the container. Harvesting is done when the foliage has dried up.