Grapes Seedlings in Kenya: Grape is not very exacting about temperature. Consequently, it can be the grown practically everywhere in Kenya making it the fruit with the broadest geographical distribution.
Kenya has a high potential to be a leading producer of the grapes if its cultivation is taken seriously. We can save a lot of foreign exchange as over 90% of the fruit used in wine and juice making is imported from South Africa and other countries.
Establishing an orchard
To establish a grape orchard, you need the right planting material. Grapes happen to be propagated vegetatively; this means, parts of the plant are cut, rooted and used to generate other plants. The most common method used in the vegetative production of grapes is stem cuttings.
If you are growing grapes for the first time you can obtain the cuttings from other grape farmers in Kenya or at Farmers Trend Nursery by contacting 0790-509684. But if you already grow some grape vines in your farm in Kenya all you need to expand your farm is the vegetative propagation of the vines. Spacing of 1.5 x 2.7mtrs is ideal when planting. One single tree can produce around 15Kgs of grapes with a lifespan of more than 30years.
Other grape vegetative propagation methods include; layering, budding, grafting and tissue culture.
Layering is used in cultivars that are difficult to root while budding is used to rejuvenate old vines.
On the other hand, grafting is done on rootstocks resistant to the grape louse, nematodes and other soil conditions like drought and low PH.
When you need clean planting materials in large quantities such that it is impossible sufficient grape stem cuttings, Tissue culture becomes handy.
Grapes can also be grown from seeds; this method is mainly use by plant breeders to grow grapes with the intention of creating new varieties or improving the existing ones.
The best time to get cuttings from grapes for propagation
is when the plant is dormant. You harvest cuttings from the dormant annual fruiting vines or canes. Hardwood cuttings of 30 cm long, each with 3-4 buds are selected from the mother-plant and treated with a rooting hormone.
Hormone treated cuttings are then stuck in a nursery to root and develop leaves. After rooting and leafing takes place, they are ready for transplanting to the main farm.
The existing varieties can be classified into two distinct groups according to their functions
1. Table grapes- this group of grapes is used in making various meals for example as sweeteners in cakes.
2. Wine grapes-used specifically in the production of wine.
Environmental conditions for grapes.
The crop prefers warm to hot temperatures; during fruiting, the weather must be sunny and dry.
Warm environmental temperatures during fruit ripening are vital in increasing the sugar content of berries while reducing their acidity.
This explains why grapes grown under irrigation in hot deserts or semi-deserts are sweeter than those from cold, humid areas.
The crop can grow in any soil, from sandy to heavy clays but the land should be deep and well drained.
Where the rainfall is scant, supplement it with irrigation of 500 mm of water during the cropping season. In Kenya, the cropping season is September to March.
Irrigation should be withheld after the long rains to force the crop to go dormant.
In August to September, fruit buds form thus it is essential to keep the plant healthy and well manured.
Suitable Grape scions for Kenya are as follows
Table grapes: Dodrilabi, Black rose, Italia, Muscat of Hamburg, Alphonse, LaSalle, Muscat of Alexandria, Perletta, Cardinal, Dalbiki.
Wine grapes: French colombard, Sauzao, Saungnok blank, Cabaret, Alicarte, Grenard, Semillon
Suitable Grape Rootstocks for Kenya
Most grape rootstocks are adapted to many soil conditions. The selection of a suitable rootstock is based on the following criteria;
- Resistance to Phytophthora root rot
- Tolerance to drought and other soil conditions like low PH
- Adaptation to soil depth and texture
- Resistance to crown gall Agrobacterium tumefaciens. This bacterium weakens vines by encouraging the production of large amounts of cytokinins and auxins that induce excessive cell division and elongation.
- Adaptation to different PH which affects availability or uptake of nutrients. The scion should be adapted to high PH soils to facilitate absorption of Fe2+ Mn2+, and Zn2+ should be adjusted to low PH to take in Mg2+, Ca2+, and K+
- Phylloxera (grape louse) and nematode resistance. Nematodes are vectors of grape fanleaf virus.Vigor control- in cold regions vines exhibit indeterminate growth. Such growth results in the diversion of food reserves to vegetative growth at the expense of the fruit development.