prick

To prick is to make small holes in prepared soil and set seedlings or seeds into them at regular spacing. The verb most commonly appears as prick out, describing the moment when a propagated seedling, still fragile and only weeks old, moves from dense seedbed to its own growing space. A prick is the hole itself; the tool that makes it is a pricket or dibber.

The job happens at a specific developmental stage. Seeds germinate together in a shallow seed tray or cold frame, growing crowded and competing for light and nutrients. Once the seedling has developed its first true leaves (distinct from the initial seed leaves), it has enough reserves to survive transplanting. At this point, typically four to eight weeks after sowing depending on the crop, the seedling is ready to be picked out and pricked into individual cells or spaced holes in potting soil or open ground.

A gardener or propagator uses a pricket, a thin wooden or metal tool with a pointed or slightly rounded tip, to open holes in the soil. Spacing varies with the crop: lettuce seedlings might be pricked into modules at 5 centimetres apart, whilst larger plants like tomatoes or brassicas occupy 8 to 10 centimetre cells or are pricked out to similar distances in a bed. The seedling is held by a leaf, never the stem, and lowered into the hole so that the soil line sits just below the seed leaves. Soil is firmed gently around the roots to eliminate air pockets.

The term appears most in nursery and propagation work, where thousands of seedlings move through this stage under controlled conditions. In commercial horticulture, pricking out has increasingly been replaced by direct sowing into individual modules or cells from the start, which avoids the labour of transplanting. However, small-scale growers, heritage vegetable breeders, and intensive hand-tended systems still rely on the practice because it allows flexible adjustment of plant density and gives weak seedlings a second chance before final planting.

Failure in pricking typically follows damage to the stem during handling, insufficient firming of soil leading to air pockets around the roots, or transplanting at the wrong stage when the seedling is either too fragile or too advanced to establish quickly. The name itself derives from the pointed action and small hole, shared with the prick made by a needle or thorn.