Boysenberry Plant: Growing & Care Guide


Boysenberry Plant Overview

Plant Type: Perennial
Family: Rosaceae
Sun Exposure: Full sun
Watering: Abundant water
Size: 5-6 feet height
Hardiness Zones: 5–9
Soil Type: Well-drained soil
Soil pH: Slightly acidic
Propagation: Stem or root cutting, tip layering
Toxicity: Non-toxic

Welcome to our comprehensive guide on growing and caring for boysenberry plants! As a delectable hybrid of raspberries and blackberries, boysenberries (Rubus ursinus x Rubus idaeus) are part of the rose family and share the common characteristics of brambles, such as thorns. Despite their prickly nature, these cane fruits are a delightful addition to any garden.

Boysenberries thrive in full sun, requiring 6-8 hours of sunlight daily. Remember, they can live up to a decade, so choose a long-term location with well-drained soil, such as raised beds. Water boysenberries 1-2 inches weekly, adjusting for rainfall, and apply a balanced, slow-release fertilizer in early spring. Install a trellis or wire system to support growth and improve air circulation, reducing disease risk. Prune in late winter or early spring, removing dead or damaged canes to encourage new growth and abundant harvests. Monitor for pests like aphids and spider mites, treating with insecticidal soap or other organic solutions. Watch for fungal diseases, applying a fungicide as needed. Harvest fully ripe boysenberries between late June and early August, depending on the region. Enjoy these plump, dark berries fresh or in various recipes.

Boysenberries are not hard to grow if you meet their requirements on a few things. In this complete guide we’ll cover all the steps to grow and care for your Boysenberry plants.

Boysenberry Plants

Growing Boysenberries  

Boysenberries are black and are made up of drupelets, or individual fruits with a seed each in them.  They look like blackberries and the fruit is about the size of a large blackberry.  

Site Selection  

Choose a site that offers full sun, well-drained soil, and easy access to water, as boysenberry plants have a lifespan of over a decade. Although they tolerate wet, heavy soil, they flourish in lighter soil. Raised beds are an excellent choice since roots typically remain in the top 20 inches of soil. Additionally, ensure that the location is protected from strong winds, as this can damage the canes and hinder pollination. Remember to leave ample space between plants for optimal growth and air circulation.

Boysenberries Variety Choice  

Obtain certified virus-free plants from a reputable grower. Planting bare root varieties in early spring is preferable to potted plants. Order your plants early so you will get a good selection of plants, and consult your local Extension service for recommended varieties in your region. Consider factors such as disease resistance, cold hardiness, and fruit quality when choosing a boysenberry variety. Some popular cultivars include ‘Thornless Boysen’, ‘Marion’, and ‘Triple Crown’, each offering distinct characteristics and flavors.

Site Preparation  

Boysenberries prefer slightly acidic soil with a pH of 5.5-6.5. Test your soil a year before planting to determine its natural pH. To increase acidity, add elemental sulfur to the ground and till it in, allowing six months to a year for the pH to adjust. While preparing the site, also consider amending the soil with organic matter like compost, which improves drainage, aeration, and fertility. Remove any weeds, rocks, and debris from the area to create a hospitable environment for your boysenberry plants.

Building The Trellis  

Boysenberries should be trained on a trellis as if they were trailing blackberries.  The easiest way to do this is to put a large wooden or metal post (3-4 inches in diameter and 6 feet high) at both ends of the row.  Put metal T posts in every 15-20 feet.  Run 12-gauge wire along the top of the posts and attach the wire to each post.  Put a wire tightener on each end of the wire.  Run a second wire about knee height.  The bottom wire should be on S hooks and not permanently attached to the posts.    


Boysenberries are black drupelets that grow on canes from a perennial crown. They require full sun, well-drained soil, and a trellis for support. Choose virus-free stock, prepare the site with slightly acidic soil, and build a trellis.

Planting  Boysenberries


Planting Boysenberries

Spacing and Support

When planting boysenberries, proper spacing and support are crucial for their growth and productivity. Space individual plants four to six feet apart to ensure ample room for growth and optimal air circulation. Maintain a distance of about 10 feet between rows, which will make maintenance and harvesting more manageable. Position the plants next to a trellis, T-post, or wire system, as this will provide essential support as they grow, helping to keep the canes off the ground and reducing the risk of disease.


Space plants 4-6 feet apart with 10-foot row gaps; use trellis or T-post for support and disease prevention.

Planting and Initial Care

When planting, ensure that the hole is deep and wide enough to accommodate the root system without bending or breaking the roots. Bury the crowns just under one inch of soil to promote healthy root development and protect them from exposure. To encourage the crown to generate new canes, trim the existing canes back to approximately two inches in length. This pruning will stimulate growth and lead to a more robust plant.

After planting, thoroughly water the boysenberries to help them settle in their new environment and establish a strong root system. Continue to monitor the soil moisture, especially during the initial weeks, to make sure your newly planted boysenberries have the best possible start in their new home. Remember that consistent care during the early stages will lead to a more fruitful and healthy boysenberry plant in the long run.


Bury crowns under 1-inch soil, trim canes to 2 inches, water thoroughly, and monitor soil moisture during early growth.

Boysenberries General Care  

Once the boysenberries are planted, they require a certain level of care.  Here are the particulars.  


Newly planted boysenberries need an inch of water every five days from planting until they go dormant in the late fall.  Plants one-year-old and older need an inch of water a week from early spring through late fall.  If you live in hot water, switch back to watering every 5-days when it gets hot.  In the winter, water once a month on a warm, sunny day.  


Every year, before the growing season starts, have a soil test done.  You can get sample bags and instructions from your Extension agent.  Fertilize according to the soil test results.  Otherwise, fertilize the newly planted boysenberries with a balanced 10-10-10 fertilizer. Give it to the plants two weeks after planting, then a month after that, then a month after that.  In the second and following years, fertilize with a balanced fertilizer such as 16-16-16 in early spring as new growth starts.  


 Boysenberries are self-pollinating.  However, the fruit is bigger when the flower is pollinated by a bee.  Native bees sometimes use the hollow stems to nest in.  


 By mulching around the plants after the soil warms, you can help keep weeds out of the cane patch.  The mulch also helps keep moisture in and the soil cooler when it is hot.  You will need to put down about three inches of mulch.  When you do, put some Nitrogen fertilizer on the mulch so it will not take the Nitrogen the plant needs.  Do not use plastic mulch cloth or weed barrier fabric as this will prevent the primocanes from growing out of the crown.  


Boysenberries require consistent watering, annual soil tests, and fertilization. They are self-pollinating but benefit from bee pollination for larger fruit. Mulch around plants to control weeds, retain moisture, and regulate soil temperature. Avoid using plastic mulch cloth or weed barrier fabric to allow primocane growth.


Pruning and Training Boysenberries

You do not have to prune your berries or train them to grow on a trellis.  If you do not do so, you will have a bramble patch which makes it hard to reach all the berries.  Training the plant to trellis leaves a clean row where you can reach most of the berries without a problem.  It also cuts down on snakes and other wildlife that might injure you when you are harvesting the fruit.  

The first year boysenberries are grown, train the canes up the trellis.  Bundle them together and tie them with twine.  Do not use plastic or wire as it will cut the canes.  If the canes reach the top of the trellis, weave them in between the top wire and the lower wire and spread them out.    

The second year, and all years after this, you will have the floricans on the wires.  The primocanes should be laid under the wire lowest wire on the ground.  In autumn, after the flowers on the floricanes and any fruit are done, the floricanes will die.  Prune them out at this point.  Remove those canes from the wires.  Lift the primocanes up onto the wires and weave them in between the two wires. 


Pruning and training boysenberries on a trellis creates easier access for harvesting and reduces wildlife risks. Train first-year canes with twine, and in the second year, lay primocanes under the lowest wire. Prune dead floricanes and weave primocanes between wires.

Boysenberries Diseases  

Boysenberries are prone to numerous diseases.  Not all diseases are problems in all locations.  If your boysenberry has a disease and you cannot identify it, take a sample to your Extension agent. They will be able to identify it and tell you how to get rid of it. 

  • Algal Spot: Light green to light orange spots appear on the cane and slowly take over the entire cane.  
  • Cane and leaf spot: Small lemon yellow sores appear on the canes and leaves.  The canes crack and dry and the leaves dry out.  Cut off the canes and burn them or place them in the trash.  
  • Orange rust: This starts as small yellow spots on both sides of the leaf.  On the underside of the leaf, these join into large pustules.  These burst to reveal large quantities of orange spores.  Remove the plant and destroy it.  
  • Yellow rust: This is similar to orange rust, but the spots stay yellow.  Canes tend to dry out and crack, while leaves release large amounts of yellow spores.  
  • Anthracnose: In the spring, there are small purplish spots on the canes and spots with purple margins on the leaves.  The spots on the canes become oval, enlarge, and cause the cane to die back.  
  • Fruit rot: There are many kinds of fruit rot.  They are mainly fungal and grow best in wet, mild weather.  
  • Cane Gall, Crown Gall, and Hairy Root Cane: Cane galls form long, cane-splitting masses.  Crown galls are large galls on the crown or upper roots.  Hairy root is small, fine roots coming out of the lower cane.  All plants with these problems need to be destroyed.  Do not replant boysenberries there.  
  • Septoria Leafspot: This starts with small spots on the leaves with tan centers.  The spots tend to remain small and do not cause any major problems.  
  • Verticillium Wilt: Boysenberries are highly susceptible to this disease.  The disease starts at the bottom of canes and works its way up.  First year canes have leaves that turn pale green, then yellow.  They fall off early.  Second year canes have leaves turn yellow and wilt.  This kills the plants in one to three years.  


Boysenberries are susceptible to various diseases, including algal spot, cane and leaf spot, orange rust, yellow rust, anthracnose, fruit rot, cane gall, crown gall, hairy root cane, septoria leafspot, and verticillium wilt. Consult your Extension agent for identification and treatment options.



There are several pests that eat boysenberries.  It is important to know which pest you have so you know how to treat it.  Take a sample and submit it to your Extension agent.  They will be able to identify it for you and suggest a treatment.  

  • Spotted wing drosophila: This is an invasive species that lays eggs in the developing fruit.  The larvae eat the fruit from the inside out.  The populations build up as the season progresses, so late maturing fruit is more vulnerable.  
  • Brown marmorated stink bug: This is another invasive species that punctures the fruit.  Their population also increases toward the end of the summer.  They are brown true bugs that give off an offensive odor when threatened.  
  • Apple pandemis, light brown apple moth, omnivorous leafroller, and orange tortrix moths: All of these moths lay eggs on boysenberries. The larvae feed on foliage, where the damage is usually minor, and fruit, which ruins them.  The larvae are all similar and are white caterpillars with dark heads.  
  • Raspberry crown borer: This is a stout moth that looks like a yellow jacket.  The larvae tunnel into the crown, upper roots, and cane.  This causes the cane to wilt and break off.  The larvae are white with a dark head.  
  • Red berry mite: This mite is microscopic.  It injects a toxin as it feeds that prevents that section of boysenberry from ripening.  It also distorts the flavor.  Once you notice the damage, that season’s crop is already ruined.   


Several pests can affect boysenberries, including spotted wing drosophila, brown marmorated stink bug, various moths, raspberry crown borer, and red berry mite. Consult your Extension agent for identification and treatment advice.



The boysenberries will not have fruit the first year they are in the ground.  They will have a small harvest the second year.  From the third year on they will have a normal harvest.  When the boysenberries start to ripen, begin harvesting once a day.  Only pick the ripe fruit as they will not ripen once picked.  Picking daily helps keep insects and animals from being drawn to the overly ripe fruit.  Be aware that snakes, including poisonous copperhead snakes, love berries.  Watch where you are putting your hand.  It is wise to wear gloves when harvesting to protect against the thorns.  The fruit is fragile and only keep s a few days so refrigerate immediately.  You can freeze the berries by putting them in one layer on a cookie sheet and putting them in the freezer.  After they are frozen, put them in a zip close freezer bag so they do not take up so much room.  


Boysenberries bear fruit from the second year, with full harvests from the third year. Harvest ripe berries daily, wearing gloves for protection. Refrigerate or freeze them immediately for storage.

In Conclusion

Boysenberries are a delicious fruit that is not hard to grow. This hybrid of blackberries and raspberries acts more like a trailing blackberry than a raspberry. A boysenberry patch can last over a decade and produce a quart of boysenberries per linear foot of canes. The canes can each grow to be 15 feet long, so it does not take a lot of plants to have lots of berries. 


Do Boysenberries Grow on a Bush or Trees?  

Boysenberries grow on trailing canes that emerge from a perennial crown. While these canes typically have thorns, some thornless varieties exist. First-year canes, called primocanes, transform into fruit-bearing floricanes in their second year. These floricanes can reach up to 15 feet in length and yield roughly a quart of berries per linear foot. To facilitate growth and harvesting, use a trellis to support the canes. Trellising also helps maintain good air circulation, which minimizes the risk of fungal diseases and makes it easier to manage pests.

A successful boysenberry harvest requires more than simply planting them. Proper site selection, preparation, and care ensure delicious berries for years to come.

Can Boysenberries Grow in Pots?  

Boysenberries can grow in pots, if the pot is at least 25 inches deep and around two feet in diameter.  While a half whiskey barrel works, the canes will grow long and spread out from the container.  It is really better to plant the berries in the ground.  If you do decide to use a barrel, place an acidic soil mixture in there. Plant your boysenberry plant with an inch of dirt over the crown and trim the canes to two inches long.  Water the plant in.  

Article Sources:

Table of Contents