Winter Squash: Saving Seed
Winter squash has harder skin than summer squash does; its flesh is firmer too and so needs to cook longer. The seeds are fully developed when the squash is ready to eat, whereas summer squash needs to be left on the vine well past the eating stage to complete the development of its seed.
Understanding Pollination
Before you try to save seeds from your winter squash, it’s important to understand the way they become pollinated.
Winter squashes, along with all cucurbits, are cross-pollinated. This means that they have both distinct male and distinct female flowers. They rely on insects to pollinate them. Because of this, it is easy for two varieties of winter squash to cross-pollinate and produce seeds that will not grow out true to their parent. Winter squash may cross-pollinate with summer squash, zucchini, and pumpkins as they are all the same species. However, don’t worry about this if you are just interested in getting winter squash for eating. Any crossing will not affect that year’s fruit, only the seeds.
If you want to save your own winter squash seeds, only grow one type of squash in the garden. Another possibility is to hand-pollinate your flowers to prevent cross-pollination but this can be quite complicated. In order to do this, growers put small bags over the flowers and manually do the work of pollinating to keep the seeds pure. We recommend that only advanced seed savers take on this complex project.
Saving The Seeds
Harvest the winter squash as you would normally for winter storage. Allow the squash to sit for after-ripening for at least 3-6 weeks up to several months.
Wash the seeds to remove any flesh and strings. Cure the seeds by laying them out in a single layer on a paper towel to dry. Store them this way in a place that is dry and out of direct sunlight. Once thoroughly dried, in 3 to 7 days, store them in an envelope in a cool dry place with the rest of your seed supply. Dried winter squash seeds will store up to 6 years if kept in cool, dry conditions.
Pumpkin seeds in particular are delicious as a snack. Check out this recipe for Spiced Pumpkin Seeds.
Learn more about seed saving here.
Interested in learning more? The Grower’s Library at Johnny’s Selected Seeds may have the information you’re looking for.