Muscadine Plant Care

Soil Qualities

• Although muscadine grapes demonstrate a good amount of drought tolerance once plants develop an established root system, dry soils can limit fruit production. Plant these grapes in a slightly acidic soil -- pH 6.0 to 6.8 -- that is evenly moist but well-drained. An organic-rich soil is best as it contains nutrients and is porous for easy penetration of roots and facilitates root gas exchange. To conserve moisture, place a 3-inch layer of organic mulch over the soil of the broad-reaching root zone.

Plant Establishment

• The ideal time to plant muscadine grapes is in fall about a month before the expected first frost date. While the leaves eventually drop off in time for winter, the moist and gradually cooling soil still promotes root growth and establishment well before the onset of heat the following summer. Water to maintain a moist, but not soggy, soil. Apply 1/4 pound of a balanced slow-release fertilizer such as 10-10-10 in early spring the first year after planting. In the second year, double the dosage and by the third year after planting and beyond, 1 to 2 pounds per plant. Two-year-old and older plants benefit from a second fertilizing of the same rate in very late spring.

Fruit Development

• Muscadine grape varieties are either self-fertile or self-sterile. Self-fertile grape plants produce flowers with both male and female sex organs and readily produce fruit once insects pollinate the blossoms. Self-sterile varieties are female vines that must have another plant nearby that produces male blossoms and pollen to yield fruits. Irrigate the soil to supplement rainfall in spring and summer to prevent drought stress. Dry soil leads to flower or young fruit abortion in an effort to conserve plant moisture. Weed the garden as well, and prevent neighboring plants from shading the leaves of the muscadine, which can slow the fruit maturation or quality of fruit flavor later on.

Pruning

• All grapevines, including muscadines, flower and fruit on current season growth. Muscadines may be grown on trellises, fences or allowed to scramble over shrubs and trees on the woodland edge. Pruning vines every late winter promotes good health and lots of vigor for increased fruit production. Muscadines are spur-pruned. Remove all weak, thin branches from main plant vines so only the strongest laterals remain. Then cut back the strongest laterals -- the spurs -- so that two buds remain on each. That summer, those two buds grow long stems that bear fruit. In the subsequent years in late winter, remove the lowermost spur on the laterals and retain the next two spurs farther up, creating two new spurs. Again cut back each spur so only two buds remain.