I must say, though, that cutting pumpkins before their prime does go against the grain. The upside is they make for far better eating – sliced, oiled, salted and baked with garlic – than when they’re big and as tasty as an overripe cucumber.
When your chosen pumpkin reaches the size of a football, set the fruit on a 4in bed of straw to protect the skin from stones in the soil and spread the pumpkin’s weight as it swells. Position so that the pumpkin reclines with the stalk and the stem to one side, then carefully bend the stem into a U shape to give the pumpkin as much growth space as possible. Moving a pumpkin is a delicate operation, particularly while it is in fast growth: the skin is so thin a fingernail will cause sap to bleed from the wound.
If this happens – or worse, a bird pecks your prize-winner – sprinkle with fungicidal sulphur dust to cauterise the cut and prevent infection from entering.
Watering is essential
Water is by far the most important influence on a potential prize-winner, accounting for a fluctuating 90 per cent of the weight. During dry weather, the leaves draw moisture out from the fruit to keep growing, which reduces the size of the pumpkin.
So keeping the roots hydrated is key. Do this with a hose or water butt set to drip alongside where the main stem meets the soil, or, better still, with soaker-hose laid in a spiral beneath the leaves and plumbed to the garden tap.
With the hose left to run for an hour every day – more if the weather is hot – the pumpkin will quickly start to plump up. During the most vigorous growth phase, a champion can bulk up 24lb a day. Yours might not gain weight this quickly, but the difference in growth from day to day will almost certainly be noticeable.
When watering, avoid wetting the foliage – this invariably leads to an attack of powdery mildew fungus that appears as a talc-like white coating on the leaves. Although the fungus won’t spread to the fruit, it curbs the capacity of affected leaves to photosynthesise, thereby reducing the growth of the pumpkin. Removing badly affected leaves and pruning side shoots that are crowded together and encroaching on your pumpkin will help to reduce this, as will feeding.