GREENHOUSES I SHADE NET I HYDROPONICS I AQUAPONICS
MELONS IN A GREENHOUSE –
the basic facts
Looking at the global hydroponics produce trends, cultivation of melons in soilless culture is a fairly new trend that is showing promising results in many parts of the world. Though you might think that the size of melons would make them hard to grow hydroponically, they grow quite well in coir substrate in greenhouses and poly houses.
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ost of the melon growers focus on growing two high quality melons per plant. Melons in hot conditions can be grown up to 4 cycles per year, as it takes around 80 days from planting to harvest. Melons are a crop that requires a very low moisture level in the final phase, just before harvest. It’s correct for all types of conditions but even more critical in tropical weather. The growers that grow melon in grow bags experience better root system, zero root diseases, less physiological disorders, more homogeneous fruit size and darker flesh colour.
Melons have to be trellised well and supported to optimise quality and appearance.
The biggest concern with growing melons hydroponically is making sure that they have a controllable growing medium, adequate light and good trellising support for their increasing weight. With the proper irrigation, lighting and maintenance of the nutrient solution levels, it helps to maximize melon production in a short period of time.
4 Undercover farming I November/December 2021 I Volume 18 No 6
Production of melon in soil versus in a grow medium, has shown a yield of 9.2 Kg/Sq m compared to in-soil production of 4 Kg/Sq m with the same melon variety. Melon seedlings should be provided by your seedling grower. This gives you as producer the peace of mind that your success in growing melons – especially as a new grower – started on the right foot. With the correct grow mix, growers succeed to grow two or three melons per plant (comparing to soil) with excellent brix levels of 15 and higher. Ideal greenhouse temperatures are between 18°C and 23°C. They should be regularly ventilated to keep air fresh and disease free. For the best yields, average root temperatures for your melons should be kept around 21°C or higher, so it helps to put the grow bags into the greenhouse well ahead of planting time, in order to heat up prior to receiving the seedlings. The pH of the grow mixture should be from 6.0 to 6.5 and contain rich organic matter. Compost or manure is best for this. Frost is an ever-present danger to production of melon, especially at either extreme of the growing season. Melons outdoors are a high-risk proposition, but they are ideal for greenhouse conditions. The melon vines will need some support once they get a bit bigger. Prepare for this early by installing trellising wires for
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