Save your own seeds - pumpkin, courgette, marrow and squash

Pumpkins, Courgettes, Marrows and Squashes

Beware that pumpkins, squashes, marrows and courgettes will all cross readily with each other.  The best way to save pure seed is to hand pollinate one or more fruits. This is very easy and will avoid disappointments with crosses.  The explanation given here is for pumpkins, but applies equally to squashes, courgettes and marrows.

Pumpkin plants have two different types of flower, male and female. The female flowers are the ones that will grow into pumpkins. They can be identified by the small immature fruit which should be obvious beneath the flower.  Male flowers just have a straight stem. You need to transfer pollen from a male flower into a female flower, making sure that no pollen gets introduced from plants of a different variety.

One evening, when the plants are just beginning to produce flowers, find some male and female flowers that are going to open the next day. Buds that are just ready to open are much fatter than the others, and they have turned from green to yellow.

You need to stop these flowers opening, so that insects can't get into them.   The easiest way to do this is to gently slip a thin rubber band over the end of the petals, to hold them shut.

The next morning go back to the plants.  Pick a male flower, take off its rubber band, and tear off the petals. Gently take the rubber band off of one of your female flowers. Using the male flower like a brush, rub the pollen on to each section of the stigma in the centre of the female flower.

Then carefully rubber band the female flower shut again so that no insects can get in with more, 'foreign', pollen.  Tie a piece of wool loosely around the stem of the female flower, so that at harvest time, you know which pumpkins you have hand pollinated.  

Now leave the pumpkins to develop and ripen. After you have harvested them, keep them in a cool dry place for another month or so to ripen further indoors.

Then cut the pumpkin in half, and scoop out the seeds, leaving the rest of the fruit for cooking as normal.   Wash the seed in a colander, rubbing it between your hands to get rid of the fibres, and then shake off as much water as possible.

Spread the seed out on a plate to dry.  It needs to dry as quickly as possible, but without getting too hot, for example on a sunny windowsill. Seeds stored in a cool and dark place will keep for 6 years.