When to plant melons?
For the RHS, sow melons indoors from mid-April to mid-May, at 18-21 °C, and plant them out in late May or June, once nights stay above 12-15 °C. In Sicily the open field runs from April through June, in Campania the written transplant starts in mid-February, and Umbria writes no month.
When, by region
| North | Centre | South | |
|---|---|---|---|
| Sowing | Indoors from mid-April to mid-May, two seeds about 1.5 cm (½ in) deep, in a 7.5 cm (3 in) pot, at 18-21 °C (64-70 °F). Up in about a week. The calendar marks April and May. Plant out in late May or June, with 3 or 4 leaves: in a greenhouse from late May, once the temperature stays above 12-15 °C (54-59 °F), and outdoors from early June, once nights do not drop below 12-15 °C (54-59 °F). The calendar marks May and June. | Umbria 2025 has melon and does not write a month. Return after at least 2 years, and the crops before and after are not cucurbits. | In Campania, transplant once the soil has settled at about 12-15 °C (54-59 °F). The transplant, in general, runs from mid-February to early March, and harvest starts after 80-90 days. Under small tunnels, late March or early April, with harvest in late June. In Sicily the open field runs from April through June. Germination wants at least 14 °C (57 °F). Growth is happy at 18-20 °C (64-68 °F) at night and 25-30 °C (77-86 °F) by day. |
| Spacing | In a greenhouse, 45 cm (18 in) at the base of the supports, one plant in a pot of at least 40 cm (16 in), or one to a growing bag. Outdoors, at least 90 cm (3 ft) if it trails, 45 cm (18 in) if it climbs. Leave 4-6 fruits under glass and up to 4 outdoors. | Umbria does not write a spacing. | In Campania, 0.8-1 plant per square metre for ordinary cultivars, and 0.5-0.7 for vigorous ones. In Sicily, 2.0-3 m between rows and 1.0-1.2 m along the row, 2,700-4,000 plants per hectare. The Campania pH sits between 6 and 7.5. |
It wants warmth. Below 12 °C, in Sicily, the plant stops growing. Frost stops it.
Mid-April to mid-May, 18-21 °C (64-70 °F), 1.5 cm (½ in), 7.5 cm (3 in), a week, late May or June, the 3 or 4 leaves, 12-15 °C (54-59 °F), 45 cm (18 in), 90 cm (3 ft), a pot of 40 cm (16 in), the 4-6 fruits and the up to 4 are from the RHS. Soil at 12-15 °C (54-59 °F), mid-February to early March, the 80-90 days, late March to early April, late June, 0.8-1 and 0.5-0.7 plants per square metre, 20-25 °C (68-77 °F) for pollination and pH 6-7.5 are from Campania. April-June, 14 °C (57 °F), 18-20 °C (64-68 °F) at night, 25-30 °C (77-86 °F) by day, soil at 15-20 °C (59-68 °F), 2.0-3 m, 1.0-1.2 m and 2,700-4,000 plants are from Sicily. At least 2 years, and the ban on other cucurbits, are from Umbria 2025, which writes no month. Courgettes, same family, are in when to plant courgettes. The months are in the February calendar, March, April, May and June.
April indoors, June outside
The RHS sows only indoors, from mid-April to mid-May. Two seeds in a 7.5 cm (3 in) pot, about 1.5 cm (½ in) deep, at 18-21 °C (64-70 °F). They are up in about a week, and you keep the stronger plant. The calendar marks April and May. In late May or June, with 3 or 4 leaves, plant them without a sharp drop in temperature. In a greenhouse, from late May, once it stays above 12-15 °C (54-59 °F). Outdoors, from early June, once nights do not drop below 12-15 °C (54-59 °F), after hardening off. Cantaloupe is the type the RHS names for outdoors. Honeydew does better in a greenhouse.
Under glass, 45 cm (18 in) at the base of the supports, and a pot of at least 40 cm (16 in) for one plant. Outdoors, at least 90 cm (3 ft) if it trails and 45 cm (18 in) if it climbs. Aim for 4-6 fruits under glass and up to 4 outdoors. The fruit is ready when it smells and the stalk starts to crack. The pot is in starting seeds indoors.
Campania and Sicily
In Campania, transplant once the soil has settled at about 12-15 °C (54-59 °F). The transplant, in general, runs from mid-February to early March, and harvest starts after 80-90 days. Under small tunnels, the transplant is in late March or early April, and the harvest in late June. Ordinary cultivars sit at 0.8-1 plant per square metre, vigorous ones at 0.5-0.7. The pH is between 6 and 7.5. Above 30 °C (86 °F) the plant slows, flowers drop and fruits distort. Pollination is happy at 20-25 °C (68-77 °F), at 60-65 per cent humidity. Outside mountain zones the succession is five years, with at least three crops and at most one repeat.
In Sicily the open field runs from April through June, with plants raised in modules. Between rows 2.0-3 m, along the row 1.0-1.2 m, 2,700-4,000 plants per hectare. Seed wants at least 14 °C (57 °F). Growth is happy at 18-20 °C (64-68 °F) at night and 25-30 °C (77-86 °F) by day. Below 12 °C (54 °F) the plant stops growing. The soil, for an early crop, is happy at 15-20 °C (59-68 °F), and a mulch helps. The better spell for growth is between the end of spring and summer. Umbria, in 2025, has the sheet and does not write the month. Return after at least 2 years, and the other crops are not cucurbits. One repeat in five years, if the variety resists Fusarium or the plant is grafted. In 5 years you may also follow melon with watermelon, or the reverse, with varieties that resist fusarium wilt, grafted or not. Watermelon is in when to plant watermelons.
Water the soil, not the leaves
Keep the soil moist, not sodden. Water the ground, not the leaves. Under glass, water regularly, especially while the fruits are forming. Once they start to ripen, and the foliage dies back in late summer, the RHS stops feeding and cuts the water. On young fruits, at about 2.5 cm (1 in), leave the best, one or two on each side-shoot, and take the rest off. How much is in watering, and powdery mildew in the courgette powdery mildew guide.
In crop rotation melons, pumpkins and cucumbers go wherever suits you, without repeating them too often. In Umbria the written gap is at least 2 years, with no other cucurbits in between.
In the app
Every plant in the catalogue has its own sowing calendar, and weather alerts for your area help you judge whether to sow now or hold off.
Frequently asked questions
When do I sow in the north?
Indoors from mid-April to mid-May, at 18-21 °C, two seeds about 1.5 cm deep in a 7.5 cm pot. Plant out in late May or June, with 3 or 4 leaves. In a greenhouse from late May, above 12-15 °C. Outdoors from early June, once nights do not drop below 12-15 °C.
What date does Campania write?
Soil at about 12-15 °C. Transplant in general from mid-February to early March, harvest after 80-90 days. Under small tunnels, late March or early April, harvest in late June. Density 0.8-1 plant per square metre, or 0.5-0.7 if the cultivar is vigorous.
What about Sicily and Umbria?
Sicily, open field: from April through June, 2.0-3 m between rows and 1.0-1.2 m along the row. Germination from 14 °C. Growth at 18-20 °C at night and 25-30 °C by day. Umbria 2025: no month. Return after at least 2 years, with no other cucurbits.
How far apart?
The RHS: 45 cm in a greenhouse, at least 90 cm outdoors if it trails, 45 cm if it climbs, a pot of at least 40 cm. Campania: 0.8-1 or 0.5-0.7 plants per square metre. Sicily: 2,700-4,000 plants per hectare. Umbria does not write a spacing.
How many fruits do I leave?
The RHS aims for 4-6 fruits under glass and up to 4 outdoors. At about 2.5 cm, leave one or two fruits on each side-shoot. Cut them when they smell and the stalk starts to crack. Under glass, from late July into early autumn.