Prune periwinkles back to about four inches tall with clean, sharp shears in early spring to reduce the plant's natural tendency toward ranginess. Do this immediately following the last predicted frost for your area and before new growth begins.

When should vincas be pruned?

When to Prune

Prune creeping vinca in the winter or very early spring for the best results, advises Fine Gardening. Avoid pruning vinca minor during May and June while it's in bloom to keep from losing the colorful blossoms before they die a natural death.

How do you keep Vinca from getting leggy?

Pinching. Caring for bedding plants often includes pinching. Pinching means to remove new growth at the tips of the branches so the plant does not become leggy.