How to Plant Boysenberries

Boysenberries are related to the blackberry and raspberry.

Enjoy fresh boysenberries without having to purchase them by growing your own. Boysenberries grow on vines and are related to blackberries, raspberries and loganberries. Boysenberries’ horizontal growth requires support wires or a trellis to support the fruit and canes. Whether you are looking for just a few berries for summer fruit or a lot of fruit with which to make jams and jellies, boysenberry plants take a small amount of work each year, but provide a great reward.

Things You'll Need

• Boysenberry plants
• Trellis or support wires
• Spade
• Compost

Instructions

1. Select a location in full sun that has good drainage. The location must have at least three feet of space in which the boysenberry vine can spread. Remove all vegetation from the planting area.

2. Prepare the soil. Add compost or organic material to the soil. Add sandy loam to the soil. Boysenberry roots will spread three to four feet wide, but will be shallow, so dig at least four feet wide and two feet deep when you are amending the soil. Mix one to three inches of the organic material in with the soil, and break up all soil clumps that will block root growth. The soil pH should be 6.0 to 7.5.

3. Plant during late October to mid-November. Plant the vines on a small mound or berm. Plant them to a depth in the soil equal to that at which they were planted in their containers.

4. Spread the roots in the hole carefully and cover them with soil and mulch. Add six to eight inches of mulch around the plant to help control weeds and grass around the vine.

5. Install a trellis behind and between the individual boysenberry vines. A three-wire trellis is common for boysenberries, and the lowest wire should be at 1 1/2 feet from the ground. The second should be 2 1/2 feet from the ground and the last 4 1/2 feet from the ground. If your vines are vigorous, add a six-foot wire.

6. Water the vine thoroughly and water daily if your climate is dry.

7. Prune 2-year-old canes back to one inch above the ground. Nine to 12 canes of the most recent year’s growth should be saved but cut back to six to eight feet. Cut the branches on these canes to a length of 12 inches. Wrap the remaining canes on the trellis and tie them loosely. Cut all remaining canes back to two inches above the ground.

Tips & Warnings

• Check your vines daily during the harvest season to see if your berries are ripe and ready to pick. Prune after you harvest your berries. Fertilize your boysenberry vines with a 5-2-6 mix that contains iron, manganese, zinc, molybdenum, copper, boron, and magnesium.

• The first year, no berries will be produced on the boysenberry vines. Boysenberries go bad quickly, so once they are ripe, pick them immediately.

References

• University of California Cooperative Extension: Growing Berries in the Sacramento Region
• Mahalo: How to Grow Boysenberries
• Just Fruits and Exotics: Blackberry, Boysenberry, Elderberry and Raspberry
• Pots 2 Plots: How to Grow Boysenberries - A Guide to Choosing, Planting, Training, and Looking After Boysenberries