Which horticultural practice involves trimming and shaping plants?

Pruning is the horticultural practice that specifically involves trimming and shaping plants. This practice is crucial for maintaining the health and aesthetics of plants. Pruning helps to remove dead or diseased branches, encourages new growth, and can improve air circulation and sunlight penetration within the plant. It also plays a significant role in shaping the overall form of the plant, allowing it to thrive in its environment and enhancing its appearance.

In addition to its health benefits, pruning is used to control the size and shape of plants, making this practice essential in landscape design and management. By selectively cutting back certain branches, gardeners can promote a more robust structure and encourage flowering or fruiting in many species.

Other practices listed, such as grafting, thinning, and propagation, have distinct purposes that do not primarily involve shaping or trimming. Grafting is focused on joining plant sections to produce new plants, thinning involves reducing the number of fruits or buds to improve quality, and propagation refers to techniques used to grow new plants from seeds, cuttings, or other plant parts. While all these practices are important in horticulture, it is pruning that distinctly pertains to the trimming and shaping of plants.