Watermelon is a great money maker. There are many types of watermelon on the Ugandan market. However, farmers are advised to select varieties that mature early, resist several challenges and yield well.
The market has got both open pollinated varieties (OPVs) and hybrids. Some hybrids produce fruits that are as large as 11-14kg in weight. The market for the fruits is all over the big local markets such as St Balikuddembe, Nakasero, Kalerwe, Nakawa and regional markets across the country’s big towns.
Seeds are raised into seedlings using planting pots. Planting pots are readily available across agri-inputs stores around the country.
Pots are filled with well-prepared soil that is to say a mixture of good soil and organic manure. Put one seed per pot.
Spray preventive fungicides and insecticides to the seedling in the nursery in order to raise healthy seedlings
Spraying is done once per week. Water seedling at least once per day Seedling are ready for transplanting after three weeks.
Make furrows in the garden one foot wide and 15cm deep. The furrows should be spaced 3m from each other.
The seedlings are spaced 60cm from each other in the sides of the furrows, and it should be done on both sides of the furrows.
Organic matter is incorporated in the furrows and DAP & Physiolith blend put in the holes at the time of transplanting.
Put 5g of the blend per hole at one to two weeks from transplanting drench with Fertiactyl GZ around the root zone (100ml per litre of water) One month from transplanting top dress with NPK.
The fertilisers should be placed at least three inches away from the stems because direct application on the roots may cause them to rot. Spray a foliar fertiliser application at the flowering stage (40ml in 20 litres). Make a second application after two weeks.
Melons are always attacked by fungal diseases such as powderly and downy mildews.
Preventive sprays should be often using preventive fungicides such as copper or Mancozeb.
At least on spray can be done once a week in a dry season and at least two sprays in the wet season Dosage; 70g of Mancozeb in 20-litre spray, 50g of copper in 20-litre sprayer.
Aphids and melon fruit flies are the major pests of water melon. Aphids suck sap from the leaves leading to curling of the leaves which eventually dry and lead to death of the plant Dusban always works effectively to kill the aphids.
Melon fruit fly mainly manifests at the time of flowering. The adult lays eggs in the flowers which develop eventually into larva (maggot) at the time when the fruit has been formed. The larva eats up the cells of the fruit and bores into the fruit.
This results into fruit abortions, rotting and bursting of fruits when they are not yet ready. Insecticides that control the fruit flies at this stage also kill the bees which we need for pollination.
The best remedy for melon fruit flies is to use fruit fl y traps which attract only the fruit flies and kill them without affecting the pollination activity of the bees fifteen pieces of melon traps should be enough for an acre of land.
Watermelon ready for harvesting from 100 days to 120 days from transplanting.
Watermelon are harvested as close to full ripeness as possible; this is when the fruit surface touching the ground is light yellow or when the vine closest to the fruit is starting to wilt.
The peduncle is cut off to prevent it from ripping into the skin of the fruit which can result into secondary diseases. Watermelon is prone to cracking or bursting during and after harvest due to rough handling.
Watermelon should not be thrown during handling, stepped on or stacked too high.