Black raspberries are self-pollinating. Their fruits are smaller and seedier than those of red raspberries. Black raspberries are considered a “superfruit” due to their exceptionally high level of antioxidants, which help to protect each cell in our body from free radicals. Black raspberries are used in some medicine to treat pain and bleeding in the stomach and to prevent cancer.
They are best eaten enjoyed straight from the bush, but can also be sprinkled over ice-cream and yoghurt, or added to smoothies.
Position – Plant your black raspberry bush in full sun, sheltered from the wind. This plant is able to tolerate partial shade, as well as cold temperatures of -20° Celsius.
Size – This is a bramble, so it needs a trellis or fence to climb along. Black raspberries can easily grow 3 metres in one year and bear fruit in the first year. So, give it plenty of room to stretch its branches.
Soil Type – Black raspberries prefer soil with a slightly acidic pH level of 5.8 to 6.8. It needs to drain well too so that it can retain moisture but avoid waterlogging.
Dig a 50 centimetre square hole and mix acid compost or well-decomposed compost, potting soil (if container growing) and a bag of our blueberry mix. Place the plant directly into the soil mixture and cover with mulch.
Mulch – Use a mulch of pine bark and green pine needles that is 5 to 15 centimetres thick around the base of the plant, not near the stems. Raspberries thrive in moisture-retentive, fertile, slightly acidic soils, which are well-drained and weed free. Mulch plays an important role in creating these optimal conditions.
Make sure not to have your mulch touching the branches of the plant. This may cause the branches to rot and get infected, especially with new branches (one and two year old boughs).
Watering – In very hot weather, water your bush once a day. When conditions cool down a little, two or three times a week should suffice. Do not overwater your bush as this causes root rot. Black raspberries can be planted at any time providing the soil is not waterlogged.
Fertilising – Apply a slow-release, organic fertiliser once in spring and again in summer.
Pruning – Cut back dead canes during the winter, and prune canes that have borne fruit to promote new growth.
Pests – As raspberries produce hard wood canes, watch out for borer.
Harvesting – Our black raspberry variety has multiple fruit flushes, but generally starts fruiting during the middle of the summer season (around December) and can continue right through winter, if the cold is not too harsh.