There are three groups of sweet melons. Canteloupe melons, with their orange flesh are the best ones for us to grow in the UK. You can also grow honeydew types, which have firm yellow flesh, and musk melons, which must be grown in a greenhouse.
For best results in our cooler climate grow your melons in a greenhouse or coldframe, or against a sunny sheltered wall with a cloche covering them.
Jobs to do now
- Keep coldframes or cloches well ventilated and shaded if hot
- Feed with a high potash fertiliser
- Keep well watered
Month by month
Sow two seeds 1.5cm (½in) deep from mid- to late April, in small pots a propagator or on a sunny windowsill at 18-21ºC (64-70ºF). Remove the weakest seedling after germination.
If you're growing your melons outdoors, harden off (acclimatise to outdoor conditions) from late May to early June, once there is no danger of frost and when they have three or four leaves.
Melons are tender plants, so need a warm, sunny spot with high humidity. In the UK it is best to grow in a glasshouse, polytunnel or under a cloche or in a coldframe.
Melons need a fertile, moisture-retentive and well-drained soil.
Three to four weeks before planting, prepare the ground by removing weeds and incorporating up to two bucketfuls of organic matter per square yard/metre and a modest dressing of general purpose fertiliser. Water well and cover in clear polythene for a week before planting to warm the soil.
Pinch out the growing point at the fifth leaf to encourage side shoots. When they appear, retain the four strongest and remove the others.
In a coldframe, train the four shoots into an X shape. Under cloches, train one pair each way.
In very sunny weather, shade indoor crops with netting or whitewash on the glass. Keep well watered at all times. When fruit are the size of walnuts, feed with a high potash potassium liquid fertiliser every 7-10 days. Stop feeding and reduce watering when the fruits start to ripen and foliage dies back.
Increase ventilation and remove shading once plants become established, but remember to re-apply shading later in summer if temperatures exceed 25ºC.
Make sure you ventilate the greenhouse or open up tunnels and coldframes when the plants are in flower, as this will allow access for insects and help the plants to be pollinated and produce a crop.
It’s best not to pollinate by hand as the small flowers are delicate, but occasionally it might be necessary - female flowers have a small undeveloped fruit behind them; male flowers do not. One male flower pollinates four females.
When fruit are gooseberry size, select the best four on each stem and remove all other flowers, fruit and leaves.
Stop the side shoots two or three leaves beyond these fruits, pinch out the main growing tips and remove new growths as they appear.
Place the fruit on a tile or piece of wood to prevent discolouration or rotting.
Melons ripen from mid-summer onwards. Harvest when the fruits produce their characteristic melon fragrance and start to crack near the stem.
Glasshouse red spider or two spotted mite
Leaves become mottled, pale and covered in webbing, on which the mites can be clearly seen; leaves also drop prematurely.
They thrive in hot, dry conditions, so mist plants regularly. Use biological control in the greenhouse.
Appears as a white powdery deposit over the leaf surface and leaves become stunted and shrivel.
Keep the soil moist and grow in cooler locations.
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