Tips on Leafy Vegetables
Despite the fact that leafy vegetables come from a very wide variety of plants, most actually share similar practices of cultivation. The most important crops in this category are lettuce and spinach. Whilst these vegetables can grow in cool to warm climates, most types of greens prefer mean temperatures of between 15°C and 18°C. They can also tolerate temperatures of up to 24°C as well as weak frosts. Ideally, the soil should be loose, fertile and moist. These crops grow best in a soil with a pH ranging from 6 to 7.
Leafy vegetables generally have quite high requirements for both phosphorous (P) and potassium (K) and rather low requirements for nitrogen (N). K requirement is often double the requirement of N, as indicated in the table below.
Usually, all P is applied at planting, while N and K requirements are often applied as split top dressings or via a fertigation system throughout the season. Spinach is also rather sensitive to magnesium and boron deficiencies.