How to Grow Prima Grapes

Test the soil in a sunny area where standing water does not occur. Prima grapes need slightly acidic soil, with a pH reading between 5.0 and 5.5. Add sulfur to lower pH and lime to raise it.

Plant Prima grapevines in the spring. Dig one planting hole for every vine. Combine the soil with 1 part organic compost for every 4 parts soil. Leave 8 feet between holes when more than one vine is planted.

Set each Prima grapevine into a planting hole, distributing the roots over the soil at the bottom of the hole. Fill the hole with the soil and compost mixture you removed, taking care not to bury the lower portion of the main stem. Water well by running a hose slowly at the base of each plant for about 30 minutes.

Drive a sturdy plant stake into the ground 3 to 4 inches from the vine. Tie the vine to it with nursery tape or cloth strips.

Fertilize Prima seedless grapevines once each year in spring. Grapes do well with animal manure, compost or a commercial plant food with an N-P-K ratio of 10-20-20. Follow the label directions for application specifics.

Prune Prima grapevines in the winter, during their dormant season. Clip off up to 90 percent of the current year's growth to encourage fruiting the next summer. (See the Resources section for detailed information about proper pruning).