Sow marrow seed indoors from April to May for transplanting later on, or direct sow outdoors from late May to June. Prepare the soil in early spring by adding plenty of well rotted farmyard manure to improve its structure and fertility.
Indoors, sow seed at a depth of 2.5cm (1″) into individual 7.5cm (3″) pots of free-draining, seed sowing compost. Place in a propagator or seal container inside a plastic bag at a temperature of 20-25C (68-77F) until germination which takes 5-7 days. Do not exclude light, as this helps germination. Once germinated, grow marrows on in cooler conditions until all risk of frost has passed and marrow plants are large enough to be transplanted. Gradually acclimatise them to outdoor conditions over 7 – 10 days before planting marrows outdoors in rich fertile, well drained soil in full sun at a distance of 90cm (36″) apart. Cover with a protective netting or fleece to prevent attack from birds and insects. When growing marrows, a thick mulch of organic matter spread around the plants will help to conserve moisture at the roots.
Alternatively direct sow marrows outdoors at a depth of 2.5cm (1″) and a distance of 90cm (36″) apart. Sow 2 seeds per hole and thin out the weakest seedling per station after germination.
Water marrows regularly – do not allow the soil to dry out as this will impair their development. Hoe between plants regularly to prevent weeds from establishing. Marrows appreciate an application of a high potash fertiliser every two weeks during the growing season. Hand pollinating marrows is not usually required when they are grown outdoors. However, for indoor cultivation the female flowers can be fertilised by pressing a male flower against them. Begin harvesting marrows from midsummer onwards when they begin to swell. Regular harvesting will encourage more marrows to be produced. Culinary note: Marrow flowers are edible and can be eaten cooked or added raw to salads.
April, May, June
June, July, August