The crossword solution for the term PLUM, ONCE is PRUNE. Pruning is a horticultural practice that involves cutting away dead or overgrown branches, stems, and foliage to maintain the health of a plant. Pruning can also be used to shape a plant, encourage growth, and improve the quality of flowers and fruits. Pruning is an important part of maintaining a healthy garden and can help to ensure that plants remain healthy and productive.