How to Care for Mars Blue Grape Vines

The Mars grape vine is a blue-skinned, seedless variety of the Vitaceae family of plants that is used to make wine, jelly and other foods. It develops and blooms much earlier that other types of grape vines, typically producing fruit clusters in early to mid-spring. Like most other grapes, Mars vines are not very cold-hardy, and grow only in USDA hardiness zones 7 to 10.

Things You'll Need

• Water
• Mulch
• Aluminum foil
• Tent stakes
• 10-10-10 fertilizer
• Pruning shears
• Loppers
• Fungicide containing copper sulfate and lime

Instructions

1. Water the soil under the Mars grape vine to keep it slightly moist at all times. The frequency of watering depends on your soil type. To determine water needs, dig down 3 to 4 inches into the soil and grasp a handful. Squeeze the soil to see if it retains its shape. If the soil crumbles, water the vines to a 4- or 5-inch depth.

2. Spread a 3- to 4-inch layer of mulch under the Mars grape vines to help absorb heat in the late winter months. If you live in the cooler growing zones, cover the mulch with a single layer of aluminum foil with the shiny side facing upward toward the plant. Secure the foil using tent stakes around the perimeter.

3. Spread a balanced fertilizer, such as 10-10-10, to the soil under Mars vines that performed poorly the previous year. Apply the fertilizer at the rate specified on the package and water the soil well afterward.

4. Prune the grape vine in the winter when the vine is dormant. The year after planting, prune off all branches but the strongest one. The next year, prune off all but the two strongest canes. In all following years, prune off all but the three strongest canes each year. Make each pruning cut using loppers as close to the main vertical trunk as possible.

5. Watch for the development of small red-colored circles on the leaves which then turn black, indicating the presence of a disease called black rot. If black rot is detected, spray the entire Mars grape vine with a fungicide containing the ingredients copper sulfate and lime.

Tips & Warnings

• The Mars grape vines will leak sap for two to three days after pruning, but this is normal.

References

• Backyard Gardener: Vitis ( Mars Grape )
• Washington State University Cooperative Extension: Growing Grapes for Wine and Table
• National Gardening Association: Edible of the Month: Grapes
• Donnan: Grapevine Black Rot
• Don Veter: How to Grow Grapes