Istutusalat

Istutusalat is an Estonian term describing the production of lettuce and other leafy salad crops by transplanting young plants from a nursery into field beds rather than sowing directly in the final site. The technique is commonly used in temperate regions to achieve uniform stands, reduce weed competition, and establish crops early in the season or after cool spells.

Propagation and production: Seedlings are raised in protected conditions or in seedling trays until they have several true leaves. Plants are hardened off before outdoor transplantation. Transplants are typically spaced to suit the variety, commonly about 20–30 cm between plants and 30–40 cm between rows, though spacing varies with leaf versus head types. Bed preparation includes deep, fertile, well-drained soil with adequate organic matter and a balanced fertilizer. After transplanting, irrigation is important to establish the stand; mulching can help soil moisture and weed control.

Management: Regular watering, nutrient top-dressings, and weed control are needed. Pests such as slugs and aphids, and diseases like leaf spots can affect transplants; integrated pest management is recommended. Harvest depends on the variety and desired product: loose-leaf types may be ready 25–40 days after transplant; head lettuce typically 45–70 days, either harvested as whole heads or by cut-and-come-again methods for baby leaves.

Regional use and benefits: Istutusalat supports season extension in cooler climates and can improve yield stability. It requires more labor and initial investment than direct sowing but can offer higher quality plants and better early establishment.