Bramble growing in South Africa:
As with popular blueberries and gooseberries, brambles such as blackberries and raspberries are other South African favourite berries. They can be used either as fresh fruit or for processing to be used in deserts, juices, yoghurts, drinks and jams. Brambles such as raspberries, blackberries and tayberries develop their best flavours when allowed to ripen before picking. However, once ripe the berries become soft, bruise easily and start to lose their firmness and flavour. This creates a market advantage for local growers which can provide local customers with high-quality fresh fruit.
Due to the global (and local) demand for fresh, nutrient-loaded and healthy food, blackberries and raspberries are becoming a very good alternative option. We see a healthy increase in the demand for these fruit in South Africa and also work closely with groups such as the South African Berry Producers Association (SABPA) to make sure that we correctly advise potentially new berry producers to make sure that the demands are met and we do not plant too many hectares for the currant and estimate future demand.
Brambles Untangled:
Brambles in general, refer to Blackberries or Raspberries which have edible fruit produced by many species in the Rubus genus within the Rosaceae family. There are two main subgenus, called Ideobatus (Raspberries) and Eubatus (Blackberries). There are also many hybrids among these species within the Rubus subgenus such as Tayberries, Loganberries, Boysenberries, Black Raspberries, and Yellow Raspberries, just to name a few. What distinguishes the blackberry from its raspberry relatives is whether or not the torus (receptacle or stem) stays with the fruit when picked. When picking a blackberry fruit, the torus does stay with the fruit and is eaten or processed with the fruit. With a raspberry, the torus remains on the plant, leaving a hollow core in the raspberry fruit.
Raspberries
Raspberries come in four colours, red, black, yellow and purple. A few cultivars can tolerate winter temperatures of up to -30°C and most are hardy up to -10°C. Red and Yellow raspberries belong to the same species and are the hardiest.
Black raspberries belong to a different sub-species and can be injured at temperatures at around -23°C. Their fruits are smaller and seedier than with those of red raspberries. Black raspberries are considered as a “super fruit” due to their exceptionally high level of antioxidants (anthocyanins), phenolic compounds, vitamin A, vitamin C, and other nutrients.
Purple raspberries are a cross between black and red raspberries. They are vigorous and highly productive plants. Their berry flavour makes them great for fresh eating, but excellent for preserves.
Raspberries can produce either one or two crops per year depending on the variety.
A group called summer-bearing raspberries produce a single crop during the summer season.
Another group called fall-bearing (also known as ever-bearing) provides a crop early in the summer and then another crop in the late summer to fall season.
All black raspberries and purple raspberries are summer-bearing.
Blackberries
Blackberries can be either trailing or erect types. Both of these types can also be thorny or thorn-less types. Most trailing blackberry cultivars are cold hardy up to -12°C, with the erect cultivars that can tolerate cold temperatures of up to -25°C. Most blackberry varieties take three years to reach maturity and remain productive for up to 12 years. Due to disease and pest build up it is recommended to replant every 10 years.
With blackberries (and all summer-bearing raspberries), the first year’s canes, called primo-canes only produce leaves and cane growth. These plants will ONLY produce fruit on their second year canes, called flori-canes. After fruit harvesting the floricanes, they die and new primo-canes grow to replace the old floricanes.
Fall-bearing raspberry plants will produce fruit during their first year on the primo-canes. During winter the tops of the fall-bearing primo-canes will die. New flower buds will grow on the still living floricanes from below the dead tops. Even though it is an advantage to have two crops to have a longer fruiting window, the total yield of the fall-bearing and summer-bearing plants are about the same.
| Blackberries: | 0.6 -1.0m between plants with a row spacing of 2.0-3.5m | ||||
| Red and yellow raspberries: | 0.5 -1.0m between plants with a row spacing of 2.5-3.0m | ||||
| Black raspberries: | 1.0 -1.2m between plants with a row spacing of 2.5-3.0m | ||||
| Purple raspberries: | 1.0 -1.2m between plants with a row spacing of 2.8-4.0m | ||||
The spacing between rows depends on the type of berry and the trellis system used.[/luv_icon_box]
Interesting Facts:
Raspberries are a type of fruit known as an aggregate fruit. Aggregate fruits have flowers with multiple ovaries and each ovary produces drupelets around a core formed by the flower. The fruit contain more vitamin C than oranges, are super high in fibre, low in calories and supply you with a good dose of folic acid. Further to that, raspberries are high in potassium, vitamin A, calcium and super tasty.
Overhead irrigation can be used but it may encourage diseases. Direct application of water to the root system by means of drip or trickle systems is a better practice.
The amount of water needed per plant or plantation would depend on the soil type, rainfall and climate conditions. Compared to other fruit crops, blackberries do not need much water. Care must be taken to keep the soil moist, but not overwatered especially on lower soils.
Younger, newly established plants require the most care to make sure that their roots do not dry out or get waterlogged. During the summer months, when the mature plant is growing and fruiting, about 20-30mm of water is needed per week. This amount is dramatically lowered during the winter season when the plants are in their dormant phase.[/luv_icon_box][luv_separator height=”50px”]
Here are some basic guidelines that can be followed:
- Annual applications of nitrogen are needed to sustain good yields. The amount of nitrogen depends on the age of the plant. In general, if plants are stunted with yellowish leaves, add nitrogen. Reduce nitrogen if excessive growth and poor fruit set is found.
- A complete and balanced fertilizer program should be used.
- Choose a fertilizer that is low in chlorides which raspberries are particularly sensitive to. Avoid sources of potassium chloride.
- Slow release fertilizers or well rotted manure can be applied annually early spring.
For optimum plant growth and fruit production, it is recommended to have the soil and water tested followed by leaf sample tests during plant growth.[/luv_icon_box][luv_separator height=”50px”]
With fall-bearing raspberries, Prune of all spent tops of the first year canes (primo-canes). Also prune of all the spent second year canes (flori-canes) to encourage new primo-cane growth.
With summer-bearing and yellow raspberries, thin out dormant canes and cut them back to be about 1.9m tall. Remove any dead or diseased canes. Remove all spent floricanes after the summer harvest.
The primo-canes on black and purple raspberries can be “tipped” by removing the top section (about 5-10cm), which will promote new lateral growth.
Do not tip or cut back trailing blackberries. Only prune the spent floricanes.
The appropriate means of pruning and trellising bramble plants largely depends by the species and varieties grown. More detailed information about this is available on request provided by Berries For Africa, but here are some of the basic guidelines to follow:
- Disposal of spent floricanes is important for disease and insect pest control. Trellising can be an expensive initial investment, but it greatly helps with air circulation, sunlight penetration, training of the plant growth and easier access to fruit during harvest.
- Many commercial growers cut off the first year (primo-canes) a couple of centimetres above ground. This can provide a slightly bigger crop in the next fall as this process allows carbohydrates to move to the rhizomes and roots which makes the plants more vigorous.
A trellis system must be used with trailing blackberry varieties. A trellis or wire system can also be used to keep canes and fruit from touching the ground. This practise reduces wind breakage, assists with harvesting, nutrient management and cultivation. Some erect blackberry varieties can be grown without any support, but semi-erect varieties would benefit from support.
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Proper site selection, soil preparation and plant selection are important steps in preventing problems. As a result of blackberries belonging to the same genus as raspberries, they share the same diseases including anthracnose which can cause the berry to have uneven ripening and sap flow may also be slowed. They also share the same remedies including the Bordeaux mixture, a combination of lime, water and Copper Sulphate.
There are many pesticides and fungicides registered in South Africa to be used on brambles. Consult Berries For Africa for more information.
It is also a good solution to introduce predators (friendly insects) that will feed on the specific pests found. Companies such as Koppert and Real Integrated Pest Management are some of the leaders in this field and we have successfully used many of their product.
Some diseases include root rot, cane blight, crown gall, leave spot and mildew.
You might encounter pests such as birds, spider mites, aphids, cane borers, fruit worms and beetles.[/luv_icon_box][luv_separator height=”50px”]
Brambles are delicate fruit that are mostly harvested by hand. To enhance fruit quality and shelve life, it is necessary to cool the fruit to 2°C to 6°C after harvesting as quickly as possible. Heat extractors and cold rooms are therefore ideal to use in large operations.
The berries can be stored in the refrigerator for a couple of days and have good freezing properties.[/luv_icon_box][luv_separator height=”50px”]
