Watermelon is a warm season crop popularly known for its fresh consumption and agro processing such as juice making. It contains about 6% sugar and 92% water by weight. Watermelon farming in Kenya is done mostly in hot regions like Makueni, Machakos, Kajiado and the coastal regions. Watermelon farming can also be done in cold regions although the quality of fruits is inferior compared to those grown in hot regions. Watermelon farming is easy as it requires minimal management processes, and the market is readily available.
Health benefits and nutritional value of watermelon
- High in lycopene, a powerful antioxidant which is effective in preventing some forms of cancer and cardiovascular diseases.
- High in Vitamin A, C and B6.
- Rich in Potassium which is helps in controlling blood pressure and preventing strokes.
- Rich in folate, amino acids, among other healthy components
- Low in calories
- Very nutritious
Ecological Requirements for Watermelon Farming
- Soil –The crop does well in loamy, well drained soils, rich in nutrients and slightly acidic, within range of 6.0 – 6.8 If grown in heavy soils, the crop grows slowly, and fruit size are usually of low quality Timely addition of organic material, well decomposed, can help in obtaining the right soil structure. Work the soil deeply to create optimal conditions for root development.
- Temperature – Watermelon performs better under warm temperatures and the optimum temperature range for production is 22 – 28
- Altitude – Watermelon can do well at altitudes of up to 1500m above sea level. However, lowlands are the best growing areas.
- Rainfall – The crop flourishes in regions with an optimum rainfall of 600mm per cropping season. Irrigation is important to ensure consistent availability. Water deficiency during flowering and fruit development causes serious yield reduction. However excessive irrigation makes the mature fruits split/crack, tasteless and watery.
Watermelon seed selection
In order to get excellent results, the choice of seeds is very important. Some of the commonly used varieties include Sukari F1, Zuri F1, Kubwa F1, Sugar Baby, Crimson Sweet, and Sweet Rose F1. Hybrid seeds are preferred for production of quality fruits. These are available at AgriJibu’s Online Shop.
Seed rate
Approximately 500 g of seeds is required for direct sowing in a one-acre piece of land.
How to Prepare Land for Watermelon Farming
Land preparation should be done early to allow all the weeds to dry and decompose before planting. The seeds are planted directly on the seed bed however it is possible to first raise them in a nursery bed. Raising them in a nursery bed can cause disturbances to the root system during transplanting. After sowing, the optimal temperature should be at least 25 degrees Celsius.
Plough the land and make it level with a fine tilth. Mix soil well with well decomposed manure. Make holes and place the seeds at the appropriate spacing at a depth of 2-4 cm. The plant spacing in the field will vary depending on the location, cultural practices and the method of irrigation to be used. Fruit setting is improved by using the correct spacing which should be at least 2-3m by 2-3m. The vines require enough space for their spreading.
Irrigation
Watermelon requires relatively a lot of water, therefore, sufficient irrigation should be done in order to maintain moisture consistency. If this is not done, the fruits dry inside while too much watering makes the fruits to become tasteless and watery.
Irrigation can be done through furrow, overhead or drip irrigation.
Tips!
- Fruit splitting/cracking may occur as a result of excessive irrigation after the crop had been water stressed.
- Irrigation should be reduced as the fruits reach harvesting stage. It should be stopped about two weeks prior to maturity.
Best Fertilizer for Watermelon in Kenya
In order to achieve maximum yield, timely application of basal fertilizer and appropriate foliar is recommended. At planting, D.A.P/T.S. P 50 Kgs per acre. D.A.P is preferred because it contains higher levels of phosphorus which helps the crop with root development.
Top dress with C.A.N 3-4 weeks after sowing, 50kg/acre, when vines start to develop. Second top dressing is done when the plants are about to flower. Apply NPK 50 Kg/acre.
Weeding
Weeds can significantly lower the productivity potential of the crop as they compete with crop for nutrients, water and light and harbor diseases and pests, which lowers yields. Therefore, proper weed control is very important for good yield and it also makes harvesting easier. This can be done by shallow cultivation. Hand weeding is recommended when the crop has grown enough to cover the soil.
Pruning
Excess fruits should be pruned in order to allow the right number of fruits to develop properly and obtain marketable quality. All of the unmarketable fruits i.e., the misshapen and blossom-end rot fruits are removed.
Maturity and Harvesting Watermelon
This starts about 3-4 months after planting depending on the variety and the ecological factors.
Maturity indices of watermelon
- Tendrils near fruit stem change color from green to brown
- Cracking of the stem near the mature fruit.
- The fruits when thumped with the hand produce muffled dull tone immature fruits produce metallic ringing tone.
- Mature fruits have sweet flavor, crisps texture and deep red color. Break up of green bands at the blossom end.
Note that watermelons don’t ripen after harvesting so harvesting time is important. Fruits should be cut off the vine using a sharp object rather than pulling or twisting off the vine.
