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Plant Manual for Boysenberry

To the left, you'll find all the topics covered in this Plant Manual. Select a topic to read its information.

Plant Description

Huge berries with outstanding flavor. This plant produces juicy, deep purple berries that can grow to be as big as 1½“ long and 1” around. They are delicious when eaten fresh and can be used to make truly outstanding jam. Heat-tolerant. Ripens in late July. Self-pollinating.


Plants grown in a greenhouse must be acclimated carefully before planting or placing them outdoors. This is especially true in hot or sunny locations. Many species should never be grown in full sun. Before purchasing a plant, learn about its sun requirements. Knowing the plants requirements can avoid any damage to the plant by incorrectly giving it the wrong conditions.

If your plant has been grown in a greenhouse, here are a few steps we recommend you follow:

  • After purchasing your plant, place it outside in a sheltered, shady spot or on your back porch.
  • Leave it there for 3-4 hours and gradually increase the time spent outside by 1-2 hours per day.
  • Bring the plants back indoors each night.
  • Water it regularly to keep the plant moist.
  • Occasionally spray the leaves with water.
  • After 2-3 days, move the plants from their shady spot into morning sun, returning them to the shade in the afternoon.
  • After 7 days, the plants should be able to handle the outdoor temperatures, if they stay around 50 degress F.
  • After 7-10 days, your plant is ready to be planted in its permanent location. Try to do this on a cloudy day and be sure to water the plant well.
  • Observe foliage daily. If any type of leaf discoloration occurs, put the plant back into filtered light and attempt this step at a later date.
  • Special care must be taken to avoid burning the leaves.

These are general guide recommendations. Some plants take longer than others to acclimate.


The best way to succeed is to plan before you plant. Let’s discuss location: Do you know where you want to locate your new plant? Avoid many future problems by considering all aspects of the planting spot, such as:

  • Cross-pollination
  • Sun and good soil
  • Leave space for future planting


Is a pollinator variety present? Cross-pollination by a different variety, of the same type of plant, is key to the success of many plants. In most cases, its absence is why the plant doesn’t bear fruit or produces poorly. Most berry plants are self-pollinating, but for a larger fruit and crop plant more than one variety.

Sun and Good Soil

Your plant would love a sunny place with well-drained, fertile soil. But it will be quite satisfied with six to eight hours of sunlight. Good drainage is required to keep your plant “happy.” If your soil has high clay content, use our Coco-Fiber Potting Medium or add one-third peat to the soil at planting time. We do not recommend planting in heavy, pure clay soils.

Even if your yard isn’t the most ideal location, take heart. Most berry plants are very adaptable and respond well to fertilizers, so they can get along well even where the soil is nutritionally poor. Just steer clear of sites with extremely heavy soils or very poor drainage.

Space for Future Plantings

Once you’ve found out about fruit growing goodness firsthand, you’ll want to expand your home orchard. It’s important to plan so that the future growth areas will be ready when you are.


Few things are as delicious as homegrown berries, and the success of your harvest begins right with the planting site and method. For maximum growth and yields later on, give your plants the best foundation possible.

Before Planting

Before you plant, check your soil pH. Contact your local County Extension Office for information about soil testing in your area, or purchase one of our digital meters for quick and accurate results. Ideally, boysenberries need a soil pH between 6.0-6.5. Steer clear of soils that are extremely heavy or very poorly drained.

Planting Tips

  • Pick a location with full sun, good drainage and fertile soil.
  • Set the plants 6 feet apart in rows 6-8 feet apart at the same depth that they were planted at the nursery.
  • Fill the hole with soil.
  • Then, prune the tops back to about 4 inches from ground level.
  • Fertilize and water your new plant. (If planting in the fall, wait to fertilize until spring for best results.)
  • To keep the roots moist, water every other day for the first week, then one to two times per week afterward.
  • Because they can spread, boysenberry brambles can be grown on trellises. Growing boysenberries this way uses less space and makes it easier to pick the fruit.

Additional Notes

  • Boysenberries are known as bramble fruit and are a cross between a raspberry and blackberry
  • The lifespan of boysenberry plants is 8-10 years with proper maintenance.
  • Suggested number of plants for a family of 5: 8-10 (2 plants per person).

Soil Preparation

Preparing your soil before you plant will greatly improve your plant’s performance and promote healthy, vigorous growth. It is a good idea to have your soil tested to determine if it is lacking in any essential minerals and nutrients. This can be done through your County Extension Office or with one of our digital meters.

The goal of soil preparation is to replenish vital minerals and nutrients, as well as break up and loosen any compacted soil.

When To Prepare Your Soil

Soil preparation can be done at any time that the ground is not too wet or frozen. Your trees may be planted even when temperatures are quite cool. If a hard frost is expected, it is advisable to delay planting for a while until temperatures become more moderate. Generally, as long as your soil is workable, it is fine to plant.

How To Prepare Your Soil

  • Roots grow faster when they’re spread out. Dig the hole deep and wide enough so the root system has plenty of room to easily expand. Keep the topsoil in a separate pile so you can put it in the bottom of the hole, where it’ll do the most good.
  • To loosen the soil, mix dehydrated cow manure, garden compost or peat moss (up to 1/3 concentration) into your pile of topsoil. Make sure the peat moss you get is either baled sphagnum or granular peat. You can also add our Coco-Fiber Potting Medium or 2 or more inches of organic material and work in evenly with the existing soil.

Your lawn can provide you with ideal organic materials such as grass clippings and shredded leaves. Not only will the grass and leaves break down to provide soil nutrients, but they will help loosen the soil as well. You can gather these in the fall with spring planting in mind.

Common soil amendments:

  • compost
  • sand
  • manure
  • lime
  • peat moss

Adding organic materials, such as our Coco-Fiber Potting Medium and compost will improve most every soil type. Organic materials bind sandy soil particles so they retain moisture and nutrients better. They also break apart clay and silt particles, so that water can infiltrate and roots can spread.

Soil Types

  • Clay and silt soils are made of very small particles. They feel slick and sticky when wet. Clay and silt hold moisture well, but resist water infiltration, especially when they are dry. Often puddles form on clay or silt soils, and they easily become compacted.
  • Loam soil is a mix of sand, silt or clay, and organic matter. Loam soils are loose and look rich. When squeezed in your fist, moist loam will form a ball, which crumbles when poked with a finger. Loam soils normally absorb water and store moisture well. Loam soils can be sandy or clay based, and will vary in moisture absorption and retention accordingly.
  • Sandy soils contain large particles that are visible to the unaided eye, and are usually light in color. Sand feels coarse when wet or dry, and will not form a ball when squeezed in your fist. Sandy soils stay loose and allow moisture to penetrate easily, but do not retain it for long-term use.


Until harvest season, boysenberries require little in the way of fertilizer. Then in late spring, begin a weekly feeding of half-strength liquid plant food just prior to berry formation. Suspend feeding when berry production stops.

Insects and Diseases

Every plant has the future potential for disease and insect damage. Factors such as location and weather will play a part in which issues your plants encounters. If available, disease-resistant varieties are the best option for easy care; and for all types of plants, proper maintenance (such as watering, pruning, spraying, weeding, and cleanup) can help keep most insects and diseases at bay.

Crown Gall

Plants appear stunted and slow growing. Leaves may be reduced in size, little or no fruit. If plant is dead, inspect roots for hard, woody tumors. Note: many things can cause stunted plants.

Natural Control

  • Do not plant berries in beds where they have previously grown and died for no apparent reason.

Other Control Options

  • Consult County Extension Agent


They are the size of a pinhead and vary in color depending on the species. Cluster on stems and under leaves, sucking plant juices. Leaves then curl, thicken, yellow and die. Produce large amounts of a liquid waste called “honeydew”. Aphid sticky residue becomes a growth media for sooty mold.


  • Consult County Extension Agent

Cane Borer

Adult is long-horned beetle. Larvae indicated by sawdust.

Natural Control

  • Cut out infected cane until larvae is found and destroy.

Other Control Options

  • Consult County Extension Agent

Cane Blight

Enters through wounds made by insects or mechanically. Cause large brown dead areas (cankers). Often first noticed when leaves wilt and wither. Cut back to below cankers; disinfect shears between cuts with 1 part bleach and 10-part water solution. Dispose of pruning.


  • Consult County Extension Agent

Spot Anthracnose

This disease is more common on black raspberry. Area appears reddish-brown sunken spots with purple margins and light gray centers on young shoots. Grow together into cankers. Leaves may drop early. Fruit may dry up. Over winters in lesions on old canes. Always remove and burn old fruiting canes after harvest.

Natural Control

  • Serenade® Garden Disease Control
  • Proper prune and weed control.
  • Always remove and burn old fruiting canes after harvest.

Orange Rust

Not common on red raspberry but serious on all others, especially blackberries. Underside of leaves covered with orange-yellow spores.

Natural Control

  • Serenade® Garden Disease Control
  • Remove infected plants.

Fruit Rot

Appears as gray, hairy mold. Decays blossoms, green and ripening fruits and harvested fruits.

Natural Control

  • Serenade® Garden Disease Control

Powdery Mildew

Whitish-gray powdery mold or felt-like patches on leaves and green twigs. Leaves may crinkle and cup upward. Over winters in fallen leaves.

Natural Control

  • Serenade® Garden Disease Control
  • Fall clean up of debris.


Adult is yellow to brown sawfly beetle, 1/4” long. Larvae are brown and white, 1/8” long. Adult make slits in flower buds and larvae feed on berries.


  • Consult County Extension Agent


Pinpoint size, many different colors. Found on undersides of leaves. Severe infestations have some silken webbing. Sap feeding causes bronzing of leaves.


  • Consult County Extension Agent

Japanese Beetle

Adult is metallic green beetle. Skeletonizes leaves. Larvae are a grub, which feeds on turf roots. This is more of a problem east of the Mississippi River.


  • Consult County Extension Agent

Leaf Curl

Leaves thicken and curl much like they have aphids. Spread by insects usually from June until plants ready to cultivate. This is caused by a virus and spread partially by Raspberry Aphid, which is hard to control.

Natural Control

  • Remove and burn dead canes.
  • Remove wild berries from area.

Other Control Options

  • Consult County Extension Agent


Leaves will thicken and curl, display ‘mottled’ color. There will be dark green areas and bright green areas on same leaf. Caused by a virus and spread partially by Raspberry Aphid which is hard to control.

Natural Control

  • Remove and burn dead canes.
  • Remove wild berries from area.

Other Control Options

  • Consult County Extension Agent


Pruning is an important part of proper edible plant care, but many people find the task overwhelming. It doesn’t have to be! Keep these things in mind:

  • You can have confidence in knowing that not everyone will prune the exact same way (even the experts).
  • It is best for your plant to do some pruning versus no pruning.

Pruning Tips

  • Cut the boysenberry vines close to the ground after they are harvested to encourage fresh growth, which will bear fruit the following year.
  • Water the vines thoroughly after cutting and retrain them as they grow.
  • Like other trailing vines, boysenberries should be pruned regularly. Cut canes to the ground once their fruiting is finished.


Spraying is important to the survival of your plants. To handle potential diseases and pests, reference the guidelines below to know what you should spray, and when you should use it.

Before you begin, read and follow all instructions on labels.

Natural Control

  • Serenade® Garden Disease Control for anthracnose, rust, fruit rot and powdery mildew.


Boysenberries require an average amount of water. If you receive about an inch of rainfall every 10 days or so, your plants will be fine. If it gets really dry, you can give your new plants a good, thorough soaking with a hose. Both overhead and trickle irrigation systems are ideal for boysenberry cultivation.


Are you ready to enjoy delicious homegrown fruit? Harvest is the time to enjoy the results of your hard work. Keep a few things in consideration as you reap the fruits of your labor: the best time to pick the fruit from your tree, and how to store the fruit.

When to Harvest

This perennial produces fruit on canes that live biennially; the plant sends up canes, the canes bear fruit in two years, and then the cane dies.
During the first year, no berries should be harvested. You may get small fruits during the first year, but starting with the second-year crop you will find the good harvesting fruit. In the second year harvest begins between July and August and the crop is hand-picked every 4 days. Berries should be picked during the morning hours as they become soft in the afternoon heat, then refrigerate them immediately. Berries are ripe when they turn a very dark red or black color and bruise easily.

Annual average yield per plant 4-8 quarts.


Boysenberries will keep about 5 days in the refrigerator. If you are not able to use the berries right away then put them on a cookie sheet in a single layer and freeze them until they are firm. Then put them in freezer bags to enjoy all year long.

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Which option is best for me?

Bare-root Trees

Trees that are shipped without soil to ensure good contact with soil in your yard. When shipped, they are about 3-4' tall with 3/8" or larger trunk diameter. When they mature, they will be one of three sizes*:


Matures to be about 8-10' tall and wide. Provides an abundance of full-size fruit.


Matures to be about 12-15' tall and wide. Gives maximum fruit yield per square foot.


Matures to be about 15-25' tall and 20' wide. A multi-purpose fruit and shade tree.

Stark Supreme Tree®

Top-grade, bare-root trees that give you a head start on growing. When shipped, they are about 4-5' tall with 5/8" or larger trunk diameter.

EZ Start® Potted Trees

Trees in bottomless pots that allow some roots to be air pruned, so that a dense mass of productive, feeder roots can grow within the pot to make transplanting easier. Mature sizes vary. When shipped, they are about 1-2' tall.

Select EZ Start® Potted Trees

Top-grade, potted trees chosen to give you a head start on growing. When shipped to you, they are about 3-4' tall.

*Tree sizes may vary by variety. See our Growing Guide for details.