Fertilizing Vinca Ground Cover

Vinca Varieties

• There are two varieties of vinca widely used as ground cover. Greater vinca, or big-leaf periwinkle (Vinca major), grows up to 18 inches tall with runners up to 3 feet long and blue flowers in the spring. It is perennial in U.S. Department of Agriculture plant hardiness zones 6 through 9. Lesser vinca (Vinca minor), also called creeping myrtle or common periwinkle, has slightly smaller, glossier leaves and grows only 6 inches tall in USDA zones 4 through 9. Care for the two is the same.

Why Fertilize

• In many parts of the country, both varieties of ground cover vinca are considered invasive and need little help from fertilizer. If your soil is poor, you are just establishing a new ground cover and want to encourage fast growth or you've just pruned the plant to the ground, your vinca can benefit from fertilizer. If your vinca is deep green, thick and flowering well, save the fertilizer for other areas of the garden.

When to Fertilize

• When you fertilize vinca ground cover, once a year is usually sufficient. It's best to fertilize in early spring, just as new growth is beginning. Following up annual pruning with an application of fertilizer not only helps the plant recover, but since you've just removed dead plant material and matted growth, the fertilizer can more readily reach the soil to start working.

Applying Fertilizer

• A granular fertilizer is commonly recommended for vinca. Apply a balanced 10-10-10 product -- the numbers indicate the percentages of nitrogen, phosphorus and potassium it contains -- at a rate of 6 to 8 pounds per 1,000 square feet, or approximately 3/4 to 1 pound for a 10- by-12-foot bed. Wait until the vinca plants are dry before broadcasting the fertilizer and knock it off the foliage and water it in well after application.