Description
Boysenberry (Rubus ursinus × idaeus)
Boysenberry is a delicious hybrid berry from the Rosaceae family, renowned for its rich, aromatic flavour and luscious fruits. A cross between raspberry, blackberry, dewberry, and loganberry, this vigorous, deciduous bramble offers the best of all worlds: sweet, slightly tart berries that are ideal for eating fresh or using in jams, pies, syrups, and desserts. Boysenberries are self-pollinating, easy to grow, and perfect for gardens where freshly picked fruit can be enjoyed at its best.
Long-trailing canes bear clusters of white flowers in spring, followed by a generous crop of juicy berries from early summer. The berries mature from red to deep purple-black as they ripen, developing their full sweetness when fully coloured and soft. Due to their delicate texture and short shelf life, boysenberries are rarely available in shops, making them an excellent choice for growers who want to enjoy their unique flavour straight from the backyard.
Growth Habit
Boysenberries produce vigorous, sprawling canes that can grow 2–3 metres tall and spread around 2 metres wide. The plants develop long, flexible stems that benefit from training along a trellis or support system for easier harvesting and airflow. Small white flowers appear in spring, followed by large, dusty purple-black berries that are soft, aromatic, and highly prized. As deciduous plants, boysenberries lose their leaves in winter and regrow in spring.
Climate Suitability
Boysenberries thrive in cool, temperate, and arid climates, particularly in regions with mild winters and warm summers. They prefer full sun to partial shade and are frost-hardy once established. Reliable rainfall or regular watering is important, especially during fruit development.
How to Plant
When to Plant: Plant canes in winter or early spring while they are dormant, ensuring the soil is workable and not frozen. While mature boysenberries are frost-hardy, young canes may need protection from heavy frost immediately after planting if conditions are severe. Alternatively, plant them in pots temporarily in preparation for planting in the ground once frost has cleared in early spring.
Position: Plant in a sunny position with at least six hours of direct sun daily. In extreme heat, provide some afternoon shade to protect plants and fruit.
Soil Preparation: Plant in fertile, well-drained soil enriched with organic matter.
Planting: Space plants around 3 metres apart. Dig a hole twice as wide as the root system. Position the cane so the core sits just below the soil surface; the soil marking on the cane is usually a good guide. Backfill gently and water in thoroughly.
Growing in Pots
Plant boysenberries in a very large pot or half-barrel, at least 50–70 litres or 45–60 cm wide and deep, using a premium-quality, well-draining potting mix enriched with compost. Provide a strong trellis or support at planting. Once established, care for potted plants in the same way as those grown in the ground, adjusting watering to suit container conditions.
Care and Maintenance
Watering: Water regularly during establishment and fruit development. Once established, watering is mainly needed during dry periods or when fruit is forming. Always water at the base to reduce fungal disease risk.
Fertilising: Apply a balanced, complete fertiliser in early spring to support strong cane growth and flowering. A monthly liquid feed during summer can help promote vigorous growth and fruiting.
Mulching: Apply a thick layer of organic mulch such as sugarcane or lucerne around the base to retain moisture, regulate soil temperature, and suppress weeds. Keep mulch slightly away from the crown and main stems to prevent rot.
Pruning
Boysenberries grow on a two-year cane cycle. In the first year, primocanes grow vigorously but don’t produce fruit. These canes are typically purple-brown, flexible, and strong. In their second year, they become floricanes, which are woody, brown, and brittle, and produce the crop in summer.
After harvesting, cut spent floricanes back to ground level, as they will not fruit again. While floricanes are fruiting, new primocanes will grow vigorously alongside them. Tip-prune primocanes in summer at around 1.2–1.5 metres to help manage height, control vigour, and encourage side branching for next season’s fruit. Tie these new canes neatly to a trellis or wire support to keep them organised, maintain good airflow, and make harvesting easier.
Retain 5–7 of the strongest primocanes each winter, removing any that are weak, damaged, or overcrowded. As plants mature from their third year, they may support up to 10 well-spaced canes.
Harvest
Boysenberries are ready for harvest in early summer, turning a deep purple-black when fully ripe. Pick fruit when fully coloured and slightly soft for the best flavour. Due to their delicate texture, boysenberries are best eaten fresh soon after harvesting or used immediately for preserves, desserts, and juices. Harvest carefully by hand, as the fruit is tender and can bruise easily.
Pests and Diseases
Boysenberries are generally hardy but can experience occasional pest or disease problems, particularly in humid or wet conditions.
Pests: Aphids and mites may attack new growth. Encourage beneficial insects or use organic sprays if needed. Birds are also known to target ripening fruit, so consider using netting for protection.
Diseases: Fungal diseases such as rust or botrytis can occur, especially if airflow is poor or leaves stay wet. Good spacing, trellising, and watering at the base help prevent issues.
Safety
Boysenberries are grown for their edible fruit; do not consume any other part of the plant. As this variety has thorns, handle with care and wear gloves and protective clothing. Supervise children and pets to prevent injuries. Wash thoroughly before consumption.
Supplied as a bare-rooted cane.