Description
Quarantine Note: Due to quarantine restrictions, Thornless Blackberry cannot be sent to Western Australia.
Thornless Blackberry
Thornless blackberry (Rubus fruticosus) is a fast-growing, semi-erect fruiting cane that produces abundant, juicy berries without the hassle of thorns. A member of the rose family, it combines traditional blackberry flavour with easier handling. Canes are biennial, growing annually from a perennial crown and root system, and benefit from support such as a trellis or wire. Fruit is produced in warmer months, typically from late spring to mid-autumn, depending on your region.
Thornless blackberries are self-fertile and well suited to cool, temperate, and arid climates with a defined winter and vigorous spring growth. They handle frost well, grow best with consistent moisture, and should be planted in a permanent position where they can remain productive for many years.
Uses & Nutritional Benefits
Thornless blackberries are ideal for fresh eating, baking, jams, sauces, and freezing. Nutritionally, they’re a rich source of vitamin C, vitamin K, manganese, and dietary fibre, plus antioxidants that support immune health and digestion. With no thorns, they’re family-friendly and can be grown in large pots, garden beds, or trained along fences and trellises.
They also add beauty and structure to edible gardens and are ideal for gardeners who want productive plants that double as attractive features.
Planting & Soil Tips
Plant during winter or early spring, while the plant is dormant. Select a sunny position with good airflow—thornless blackberries grow best in full sun, but in areas with intense summer heat, some filtered light or afternoon shade can help prevent sunburn and reduce moisture stress. Choose a spot that is also sheltered from strong or damaging winds, which can break or weaken the canes.
Allow 2–3 metres between plants to give canes room to grow and make pruning and harvesting easier.
Prepare the soil before planting:
- Work in well-rotted compost or aged manure to enrich the soil.
- If compost isn’t available, apply blood and bone or a balanced fertiliser—not both at once, to avoid nutrient imbalance.
- Aim for a slightly acidic pH (6.0–6.5).
- Make sure the soil is free draining, as waterlogged conditions can lead to root problems.
When planting:
- Dig a hole wide and deep enough to comfortably spread out the roots.
- Place the plant so the crown sits at soil level and roots are just beneath the surface.
- Backfill with the original soil or a soil-compost mix.
- Water in well to settle the soil around the roots.
- Apply a generous layer of mulch (e.g. straw, sugarcane, or compost), keeping it a few centimetres away from the crown to prevent rot.
Support & Cane Training
Provide a trellis or wire system to support the semi-erect canes, keeping them upright for easier harvesting and better airflow. Tie canes loosely as they grow. Separate canes by age:
- Floricanes (2nd year, fruiting)
- Primocanes (1st year, next season’s fruit)
Thornless blackberries fruit on second-year floricanes, which become woody and brown-grey after fruiting. In the first year, you’ll only have primocanes, which are green or reddish-purple and softer. These primocanes will mature into floricanes the following year, so you’ll have both primocanes and floricanes growing simultaneously.
Use a fan system by tying floricanes (fruiting canes) to one side of the trellis and primocanes (new canes) to the other. Alternatively, train primocanes to grow vertically and guide floricanes outward at an angle or along the sides. This separation makes it easier to identify and prune the right canes at the right time, improves airflow through the plant, and helps ensure better light penetration and fruit quality.
Watering, Feeding & Seasonal Care
- Spring: Water regularly; apply fertiliser if not done at planting.
- Summer: Deep watering and optional second feed.
- Autumn: Reduce watering; no fertiliser needed.
- Winter: Water only if dry. Add compost and mulch to insulate roots.
Pruning
Thornless blackberries follow a two-year cane cycle:
• Primocanes (first-year canes) focus on vegetative growth and will produce flowers and fruit the following year
• Floricanes (second-year canes) produce flowers and fruit, then die back
Primocanes
- Once canes reach 1.2–1.5 m in summer, tip the soft growing end to encourage side branches (laterals), which will produce fruit the following season.
- In late winter, shorten the lateral branches to 30–45 cm (the side shoots that grew last season), and remove any branches growing below 45 cm from the ground to improve airflow and reduce the risk of disease. Keep the healthy laterals, as they will produce fruit the following season.
- Once primocanes have fully developed, usually in late winter or early spring, thin them to the strongest 5–8 canes per plant, removing weak, overcrowded, or poorly positioned growth. This improves structure and ensures better fruit production in the coming season.
Floricanes
- After fruiting (late summer to early autumn), cut floricanes back to the base—they will not fruit again.
- Take care not to remove new primocanes—these will produce flowers and fruit next season. Continue guiding and thinning them as needed during winter.
This cycle repeats each year.
Harvesting
Thornless blackberries are ready to harvest when the fruit is plump, glossy, and easily detached. You’ll get your first harvest in the second year (after planting), when the primocanes turn into floricanes and produce fruit. Harvest every few days during the season, typically from late spring to early autumn, depending on your climate. Handle the berries gently, as they are delicate and bruise easily. Enjoy them fresh or store them in the fridge for a few days. They also freeze well for later use.
Pests & Diseases
Generally low maintenance, but watch for:
- Aphids, mites, and fruit fly—use sprays or netting.
- Botrytis or rust in humid weather—prune regularly and avoid overhead watering.
Keep mulch topped up and the area weed-free to minimise risk.
Growing in Pots
Blackberries grow well in large containers (40–50 cm wide/deep) with quality potting mix. Ensure good drainage, full sun to part shade, and a support system. Water and feed more frequently, as nutrients and moisture deplete faster in pots. They’re a great option for small spaces and productive patios.
Propagation
Easily propagated through tip layering or hardwood cuttings. Division is not necessary, as thornless blackberries do not form clumping crowns.
Safety Note
Thornless blackberries are not toxic to humans or pets. While not typically consumed, the leaves and stems are not known to cause harm. As with any garden plant, supervise young children and avoid eating unripe fruit in large amounts.
Supplied as a bare-rooted cane.