Strawberries are warm-weather fruits that grow in a rounded mounding form with outgrowing trailing vines called runners. The red fruits are preceded by delicate, white, buttercup-shaped flowers with a central yellow eye. While pruning is not usually necessary and can inhibit fruit development if improperly done, light, well-timed trimming can be used to boost fruit size and spur robust growth. Trimming should also be conducted to remove dead or damaged plant tissues so new, healthy growth can emerge.
Trim away any brown, dead, moldy, diseased or desiccated leaves and runners throughout the growing season. Cut these areas back to a point of healthy green tissue, cleaning up and and discarding the problematic cuttings.
Deadhead the flowers from the plants during their first year of growth. This encourages healthy root and foliage development and larger strawberry harvests in the long term. Trim or pinch off the white flowers from June-bearing varieties for the first year after planting. Trim or pinch the flowers from everbearing or day-neutral varieties for six weeks from the time the crowns were planted, allowing flowers to develop and remain thereafter.
Trim back any long runners that develop on everbearing or day-neutral strawberry varieties regularly. Cut the runners when they begin to spread beyond four or five inches from the main mound of the strawberry plant crown. This will keep the plant dense and encourage plant energies into developing larger fruits.