🌿 Potatoes

Use loose, crumbly, well-drained soil (ideally sandy loam to loam) rich in organic matter; avoid compaction so that tubers can develop. Maintain regular humidity but avoid waterlogging to reduce rotting and poor aeration. Slightly acidic soil is preferable (around pH 5.0-6.5); avoid over-calibration and fresh manure, which can increase the risk of common scab. Plant on raised ridges/flats where drainage is slow, and raise the soil as the stems grow to keep developing tubers covered.

Potatoes are generally planted as certified seed tubers (not real seed). Plant once the soil is workable in spring and has warmed up to around 7-10°C; avoid planting in cold, waterlogged soil. In regions prone to frost, wait until after heavy frosts, or be prepared to protect emerging shoots. Before planting, seed tubers can be "cherished" (pre-germinated) for 2 to 4 weeks in cool, light conditions to encourage short, robust shoots. Use only healthy, disease-free seed tubers. Large tubers can be cut into pieces of 2 to 3 eyes each; make clean cuts and leave the pieces to dry for 24 to 48 hours in a cool, airy place to reduce the risk of rotting. Prepare a sunny site with loose, well-drained soil and incorporate compost or well-decomposed organic matter. Avoid excess fresh manure and avoid liming near potato plantations where scab is a problem. Plant tubers or pieces with the eyes facing upwards. Planting depth and spacing : - Furrow/bridge method: plant tubers 8-10 cm deep. - Spacing: 25-30 cm inside the row. - Spacing between rows: 60-75 cm (greater spacing is useful for main crop types and for ridging). When shoots reach 15-20 cm in height, level the soil around the stems to form ridges 15-25 cm high, repeating the operation as necessary to keep developing tubers covered and protected from light (thus avoiding greening) and to improve yield. Keep the soil evenly moist, especially from the time the tubers appear until they swell, but avoid waterlogging. Mulching after plant establishment conserves moisture and eliminates weeds. Practice crop rotation (3-4 years without potatoes and other solanaceous plants if possible) to reduce disease and pest build-up.

Potatoes react strongly to potassium and need sufficient phosphorus at planting, while excess nitrogen delays tuber formation and can reduce skin quality and shelf life. Incorporate well-prepared compost before planting to improve soil structure, but avoid fresh manure as planting approaches. At planting time, apply a balanced fertilizer (e.g. 10-10-10 or 14-14-14) or a starter fertilizer emphasizing P and K, in 5-8 cm strips to the side and underside of the seed (avoid direct contact). Apply nitrogen laterally (or in two light applications) when plants are 15-20 cm tall and again at the start of tuber formation (around 4-6 weeks after emergence), then stop when tubers start to expand. If the soil is low in K, add K - often in the form of potassium sulfate (preferred over chloride sources for many table/processing potatoes) - and maintain regular soil moisture to improve nutrient absorption.

Mulch potatoes after emergence, once the soil has warmed up, using clean, loose organic mulch (straw, shredded leaves, well-prepared compost) to a depth of 5 to 10 cm. Keep the mulch slightly back from the stems to reduce disease, and top it up as the plants grow to suppress weeds, conserve moisture, moderate soil temperature, and help keep developing tubers covered (thus reducing greening). In cool, wet weather, use a thinner layer and avoid piling mulch on cold, waterlogged soil; remove or thin mulch if it remains soggy or favors slugs or rot.