Winter squash and pumpkinsCucurbita maxima, C. moschata, C. pepo

Squashes need warmth, space and light: give them the sunniest spot in the garden, protected from cold winds by a hedge, a wall or a row of climbing beans. They take up three to four square metres per plant; rather than sacrificing a bed in the vegetable garden, set them on an old compost heap, at the foot of a composter, along a fence they will climb, or on a little-used lawn they will cover. Avoid damp hollows where cold air lingers in spring and shady corners, where the fruit never ripens.

Squash is the hungriest plant in the vegetable garden. For each plant, dig a hole 40 cm each way at the end of April, fill it with a mix of half soil and half mature compost or well-rotted manure, a good barrowload per position, and shape a slight mound that will warm up faster. In our clay soils, this mound also prevents the roots from suffocating during a wet June. Cover the mound with cardboard or black plastic a fortnight before planting to gain a few degrees. No chemical fertiliser is needed, the compost is more than enough.

Sow between 15 April and 5 May, indoors, in 8 to 10 cm pots filled with potting compost. Push each seed in on its edge, point downwards, 2 cm deep, one per pot. At 20 °C, germination takes five to eight days. As soon as the seed leaves unfold, place the plants behind the brightest window or in the greenhouse, otherwise they become drawn within three days. An earlier sowing, in March, gives plants that are too large and fragile before they can be put outside. Direct sowing in stations after 15 May also works, but with a fortnight's delay.

Put the pots outside by day for a week from 10 May, in light shade at first, then in sun, bringing them in at night. Plant after the Ice Saints, around 20 May, on a mild, overcast day, using three-week-old plants carrying two or three true leaves. Make a hole at the top of the mound, remove from the pot without breaking the root ball, set it in without burying the stem, and close up. Water three litres at the base, then place a cloche or a cut-down five-litre bottle over it for the first ten nights, which are often chilly here.

Allow 1.5 to 2 m between plants for trailing pumpkins and Red Kuri, 1 m for bush varieties such as some spaghetti squashes or Jack Be Little. In a small garden, train the light-fruited varieties, Red Kuri or butternut, up a wire fence, a pergola or an old ladder: a two-kilo fruit can be supported by a string shopping bag. You can also direct the trailing stems by gently coiling the vines around the plant in a spiral as they grow. Plant at least three plants to ensure cross-pollination between male and female flowers.

On a terrace, only the small varieties are worth the trouble: Jack Be Little, Sweet Dumpling, Uchiki Kuri or bush spaghetti squash. You need a container of at least 50 litres per plant, filled with two thirds potting compost and one third garden compost, with wide drainage holes, placed facing due south against a wall. Let the plant trail or climb along the balustrade. Watering becomes daily in July-August, and a weekly liquid organic feed replaces the missing nourishing soil. Three or four fruits per plant is a fine target, not to be exceeded.

Sowing too early, in March, produces metre-long plants that languish on the windowsill. Planting in early May in soil at 10 °C halts growth for weeks. Burying the stem at planting causes the crown to rot. Forgetting that squashes of the Cucurbita pepo family, such as courgettes and patty pans, cross with each other has no consequence for this year's harvest, but makes any saved seed useless. Finally, planting ten plants in a hundred-square-metre garden is the most common mistake: three well-fed plants give a dozen fruits, plenty to get through the winter.

A mature squash loses several litres a day through its leaves in August. Water abundantly, ten litres per plant, once or twice a week in the absence of rain, always at the crown and never on the leaves, at the end of the day. Deep, spaced-out watering is better than small daily amounts, which keep the roots near the surface. Foliage that droops in the heat of the day is normal if it perks up in the evening; if it is still wilted in the morning, the plant is thirsty. Reduce water from mid-September so that the fruit concentrates its sugars and hardens its skin.

From planting, mulch generously, 8 to 10 cm deep, with straw, hay, dried grass clippings or wood chippings, over the whole area the vines will cover. This mulch keeps the soil cool, smothers weeds under foliage that makes hoeing impossible, and above all keeps the fruit off damp ground. A squash fed with compost at planting then needs only comfrey liquid diluted to 10 % every fortnight from July to the end of August, rich in potash for swelling. Excess nitrogen would give enormous leaves and few fruits.

On trailing types, pinch out the main stem above the fifth leaf when it reaches 60 cm: two or three side branches will develop, carrying the female flowers. Then, as soon as a fruit has set and is the size of a fist, cut its stem two leaves beyond. Limit to three fruits per plant for large pumpkins, four to six for Red Kuri and butternut, and remove late fruit set after mid-August, which will not have time to ripen and will weaken the others. Bush varieties need no pruning at all. Place a tile or a small board under each fruit as soon as it forms.

Powdery mildew arrives almost every year at the end of August, felting the leaves in white: space the plants out, water at the base, and spray at the first symptoms with skimmed milk diluted to 10 % or a tablespoon of bicarbonate of soda per litre of water, once a week. After mid-September, let it be, the fruit is formed. Slugs devour young plants: a cloche for the first few weeks, evening collection, well-developed plants. In cold, wet weather in June, the female flowers abort for lack of pollinators: hand-pollinate in the morning with a male flower stripped of its petals, rubbing it on the stigma.

Late April, sowing indoors and preparing the compost mounds. Around 20 May, planting under cloches and mulching. June, pinching out the main stem, watching for slugs, hand pollination if the weather is dull. July, guiding the vines, pinching beyond the fruit, first comfrey liquid. August, tiles under the fruit, limiting to three or four fruits, copious watering, dealing with powdery mildew. Early September, stopping the liquid feeds, reducing water, removing leaves that shade the fruit so it colours up. Late September to mid-October, harvest before the first forecast frost.

A squash is ripe when its stalk is dry and corky, its skin resists a fingernail and sounds hollow, and the foliage yellows. Here, that falls between mid-September and mid-October; never wait for a frost, even a light one, which compromises storage. Cut with secateurs, keeping 5 to 8 cm of stalk, and handle the fruit like an egg, never carrying it by the stalk. Then leave the squashes ten to fifteen days in the sun or in a conservatory, between 20 and 25 °C, so they heal over and harden their skin. A fruit that has dropped before ripening should be eaten within the month.