Growing and hand pollinating pumpkins

I want to move our dependence further away from the shops and closer to food we grow ourselves or find locally. I am hoping to grow enough pumpkins to store for at least six months so we don't have to buy them. Pumpkin is one of those vegetables like garlic and onions that, if stored correctly, will last quite well for a long time without you having to do anything to it.  If I can grow enough for 12 months, I'll be a very happy gardner.

The seeds I had were taken from a very good pumpkin we bought on the back roads of Queensland somewhere. It was a Japanese pumpkin with dark orange firm flesh, dark green skin and a delicious flavour. One taste and I wanted to reproduce that pumpkin. After that meal, I took the pumpkin out of the fridge, removed all the seeds and washed them. I didn't dry them because I didn't want to store them - I wanted to see if I could grow its babies and store them year after year after year.

Hanno loves eating pumpkin but he hates their growing habits. Most pumpkins will take over a small garden if you let it but I thought that if I planted my pumpkin on the edge of the garden, during our down time, that would solve the problem. In December, I planted about five seeds in three pockets in our compost heap. It was late in the pumpkin growing season, I wished I'd planted earlier but that was when I did it. Theoretically, we can plant pumpkins all year but we go very close to one and two degrees at night here during winter so I didn't want to risk it. My hope was that this one planting, if I did it organically and with care, would supply us with a crop of top quality pumpkins that could be stored. Instead of having those vines meandering all over the garden, as much as I love the look of that, I could see "someone" snapping. No, this way was better.

Pumpkins, like all cucurbits, are prone to powdery mildew - a fungal disease that causes the fruit to fall off and the vine to eventually die. Planting them in a mound - either of soil or compost, or in the compost heap itself, is ideal. About five days after I planted them, up came the shoots, green and healthy. I removed several of the smaller ones. There is a knack to watering pumpkins successfully. Watering at night or late afternoon will encourage powdery mildew so I always water in the morning. When the vines have established and sent out long shoots, roots will form under some of the nodes. Water (and fertilise) at those points too. Pumpkins are hungry feeders so the nutrients these vines extracted from the compost allowed me to skip the fertilising but I did give them a couple of watering cans full of seaweed concentrate. If you plant them in garden soil, add some nitrogen fertiliser and sulphate of potash. The nitrogen will help the green growth and the potash will encourage flowers to form.

Male flower on a long stalk.

Female flower with the small unfertilised pumpkin under the flower.

This is the stamen of the male flower with petals removed.

Pollinating the female flower with the male.

Many people get concerned when the first flowers form without it being followed by a small pumpkin coming soon after.  Pumpkins always set male flowers first. These are the flowers on long stalks and can sometimes grow 10 or 12 inches and reach up above the leaves. The male flowers are there to encourage the bees to start visiting before the female flowers grow. Another difference is that the male flowers are closer to the where the vine started growing and the female flowers are always on the vines ends as they spread out in search of sunlight. When you look at the flowers together, and strip off the petals, you'll see distinct differences. The male flowers are tall and slim and have a long stamen in the centre which holds pollen.  The females have a shorter stem and the flowers are wider. Just under the female flower sits a tiny pumpkin. At their bulbous centre is a stigma that traps the pollen to fertilise that small pumpkin.

Pumpkins are naturally pollinated by bees and ants.  The flowers are only open for a short period so if they open before or after the bees arrive, and there are no ants, they might not be pollinated. You can pollinate by hand. Do this early in the morning. Find a healthy looking male flower and peel off the petals, leaving the stamen (like in the photo above). You'll often see some of the yellow pollen has dropped to the bottom of the flower.  Find a female flower, gently open the flower and rub the stamen over the centre of the female flower. Close the flower if you can, and go on to repeat this process on every female flower you want to pollinate, using the male flower for one or two flowers only.  I tend to pollinate two pumpkins on each vine, then I get a new male flower. If you pollinate all of them, you'll get smaller pumpkins.

In a week or so, if pollination is successful, the female flower will have fallen off and the pumpkins should be getting bigger. If they are, cut off the ends of each vine. That way you can keep the plants fairly well contained. If you have a small garden you might care to try the small bush variety Golden Nugget. It produces a large apple sized pumpkin on a bush. It can be grown in a container.

Depending on the variety, pumpkins generally need about 120 frost-free days to grow to maturity. They're ready to harvest when the stem goes corky and the vines start dying off. Cut the pumpkin from the vine leaving about six inches of stem attached. Dry in full sun for about two weeks, then store in a cool, dry, rodent-free place, not the fridge, for as long as they last. Most will last at least six months in ideal conditions.  The drying process is vital because it allows the pumpkin to fully ripen, it improves the flavour and it hardens the skin enough for long term storage.  Keep the stem attached during storage but if it falls off, seal the hole with bees wax and use that pumpkin next.

Are you a pumpkin or squash gardener? What are your secrets to a good crop of pumpkins?