Do Watermelon Vines Have to Be Pruned Back As They Grow?

Significance

• Many watermelon vines can grow out of control if they're not pruned. They may dominate the garden if left on the ground or make a garden trellis too heavy if you're trellising the melon. Pruning back long vines helps you achieve a better balance between vine length and amount of fruit. Compact melon vines do not need to be pruned, thanks to their naturally smaller growth habit. If your melon variety is marked as compact --- such as "Yellow Doll" or "Sugar Baby" --- you probably won't need to prune. Otherwise, plan on trimming the vine.

Fruit Pruning

• To get the highest-quality fruit, you might need to prune some melons. Look for melons that are misshapen and malformed, and clip these off at the base. Removing the duds helps your remaining melons grow larger: The plant can put its energy into developing larger melons since it doesn't have to use energy to grow the culled fruit.

Technique

• Watermelon vines produce one main stem with many offshoots, or secondary stems. When pruning, identify the main stem --- this is the one the shoots extend from --- and leave it alone. Also leave the first offshoot, the one closest to the base of the plant. Count eight nodes out from the first offshoot and prune the secondary stems occurring at these nodes, as well as any stems growing between them. Leave the offshoots that grow after the eighth node.

Tips

• Look over your plant regularly for misshapen fruit. Remove this fruit when you notice it. Likewise, prune overgrown vines when they threaten to encroach upon other plants or when the vines cover the trellis. Never prune your watermelon plants when they are wet, as this could encourage the growth of disease.