Site

Pumpkins are gross feeders so you must give careful attention to preparing the site if you want to grow really big pumpkins.

Preferably the heap should be prepared some time before planting. Choose an open sunny site with good drainage and build a heap of well rotted compost of farmyard manure. For best results make the heap about five feet across and two feet high. Make a saucer shaped depression about nine inches deep in the centre and fill it with good potting compost in which to place the plant.

Planting out your pumpkin

Plant out your plant when the danger of frost is over. If you have a cloche use it to protect the plant for the first week or so. Water the plant well before planting it with the seed leaves just above the compost. Make sure it does not dry out. It should be growing freely in 10 to 14 days. If not then watering it with some water soluble fertiliser will help.

Building up your pumpkin

This is essential if you want to grow a mega-pumpkin. By mid June when day and night temperatures are warmer you should water it daily and make sure the heap never dries out. You may well even need to water it on days when it rains since the huge leaves act like umbrellas and keep the soil dry underneath. By late July the roots should have spread throughout the heap. You can help your pumpkin with more water soluble fertiliser and by putting soil over the stems of the vine as they trail along the ground. That will encourage more roots to grow out of the stem opposite each leaf which helps build up the plant's strength.

Training and stopping your pumpkin

Fruits can be grown on the main stem or a limited number of side shoots.

If you want to grow on the main shoot only then cut off laterals and sub laterals just beyond the second or third leaf. I can't be bothered with all that and just let it grow and chop off anything that escapes from the plot!

Don't allow any fruit to set until mid-July at the earliest. Then start to panic when you have a week or so with no female flowers!

Fertilising your pumpkin flowers

There are male and female flowers and it is essential to transfer pollen from the males to the females. You can leave it to the bees but hand pollination is more reliable. By late July the plant will be growing strongly with high nutrient intake and fruits will develop quickly when you pollinate them.

You can tell the female flowers because they have a baby pumpkin underneath the flower. To pollinate remove a male flower. Hold it by the stem and carefully remove the petals, exposing the pollen laden anthers. Apply the anthers to the stigmatic surface of the female flower so the pollen is freely transferred. This is best done early in the morning when the anthers are heavily laden with pollen. If fertilisation has been successful the baby fruit will start to swell within 2 or 3 days. Female flowers can be fertilised at intervals of a few days to make certain of setting fruit. But once you have seen that fruits are developing all but the best should be removed. How many to leave is up to you. The more fruit you allow your pumpkin the grow the smaller each one will be. So for a really big one you should only grow one fruit per plant. The trouble is that you will get no fruit at all if you only grow one and it goes mouldy. So you'll have to decide for yourself what it best.

You must not let the plant dry out at this stage or the fruit will crack.

Harvesting your pumpkin

The fruit will grow very rapidly for the first 4 or 5 weeks (sometime over 20lbs per day). After that the skin will begin to net over. The fruit will gradually harden as it reaches maximum size. It should be harvested just before the weigh in so it has as long as possible to put on weight. Frost will damage or kill the plant unless you protect it (quite a job if it is a big one). The fruit will survive a light or moderate frost if you cover it with a blanket. But a heavy frost will make it go soft so you may have to harvest it early if heavy frost is forecast.

As soon as you harvest your pumpkin it will start to lose weight though evaporation. So leave it as late as you can but watch out for that frost.

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Good Luck and see you at the competition in October