Growing melons and watermelons in Spain

Melons are among the most rewarding crops for a Costa Blanca garden because they want exactly what the summer here provides: long heat, strong light and a dry ripening period. Two different species are grown. Watermelon is Citrullus lanatus. Everything else, the cantaloupes and muskmelons, honeydew, Galia and the Spanish piel de sapo, are forms of Cucumis melo, grown in much the same way.

The types worth growing

Cantaloupe and Galia melons are netted, aromatic and quick to tell when ripe. Honeydew and the Spanish piel de sapo, literally toad skin, keep longer and store well but need a full season to sweeten. Watermelons need the most space and heat. In a domestic garden the smaller icebox watermelons are more practical than the large field types. Piel de sapo and Tendral are the melons most local gardeners will recognise from the markets, and both are well suited to inland heat.

Sowing and planting out

Melons resent cold soil and any check to growth. Sow indoors in pots in March or April and plant out only once nights are reliably mild and the soil has warmed, usually from late April on the coast. Direct sowing works from mid-spring. Harden plants off carefully and protect young transplants from wind, which shreds the large soft leaves.

Give each plant a square metre of room on the ground, or train smaller melons up a strong trellis with slings to support the developing fruit. A sunny, sheltered bed with compost dug in and sharp drainage suits them. Black mulch or fleece early in the season lifts soil temperature and brings the crop forward.

Water and feeding

Water generously and deeply while the plants are growing and setting fruit, keeping the moisture at the roots rather than on the foliage. Keep moisture consistent as the fruit swells, then reduce watering as ripening begins without allowing the plant to wilt. This lowers the risk of splitting while the foliage dies back. Container plants benefit from a high-potassium feed every 10 to 14 days once the fruit is forming, while plants in well-prepared ground may need none.

Pollination and fruit set

Melons carry separate male and female flowers and rely on bees. If fruit fails to set in a still, enclosed courtyard, hand pollinate in the morning by touching the centre of a male flower to the female, which has a tiny swelling behind the petals. Thin to two or three fruits per plant for reliable ripening.

Telling when a melon is ripe

Cantaloupe and Galia types develop their characteristic scent and the stalk begins to crack when they are ready. Honeydew and piel de sapo do not necessarily slip from the stem, so use the seed supplier's expected season together with the mature skin colour and a slight softening at the blossom end. Watermelon is usually ready when the pale ground spot turns creamy yellow and the tendril nearest the fruit has dried, but no single sign is infallible.

Problems

Powdery mildew is the common late-season disease, coating leaves in white; grow in an open position and choose resistant varieties. Mediterranean fruit fly can sting ripening fruit. Aphids spread mosaic viruses that mottle and distort the leaves, so control them early. Blossom-end rot and sun scald both follow irregular watering and exposed fruit.

Sources and review

This guide was reviewed in September 2026 using the Kew Plants of the World Online records for Cucumis melo and Citrullus lanatus, the Royal Horticultural Society melon guide and Spanish horticultural accounts of piel de sapo and Tendral production.