Saving Squash Seed
Let's talk squash! Here are some basic seed saving facts about this plant.
1. There are 3 main species you can grow in your garden without cross pollination. Cucurbita pepo, Cucurbita moschata and Cucurbita maxima
2. Squash are outbreeders, meaning insect pollinated.
3. Squash will cross pollinate very easily. Isolation by distance or hand pollination are necessary to keep varieties pure.
4. It is a good idea to save seed from as many plants as possible. On a home garden scale that would be 5-20.
So with these three facts in mind, let's have a look out in your garden. Do you have a zucchini (C. pepo) next to a spaghetti squash (also a C. pepo)? "Uh oh", as Maisie, our toddler likes to say:) Those will cross pollinate. See, they are both C. pepo. But if you have only one variety of C. pepo, one C. moschata and one C. maxima you can save the seed and expect it to be pure.
But beware! What is your neighbor growing on the other side of the fence? You need at least 1/4 mile isolation to save pure seed or you will need to hand pollinate.
For example, we are growing Costata Romanesco Zucchini (C. pepo), Buttercup Winter Squash (C. maxima) and Baby Butternut (C. moschata). That will give us a great variety of squash to eat and save pure seed.
Here are some of the variety names that correspond with scientific names.
Cucurbita pepo- most summer squash like crooknecks, zucchini, patty pans and winter squash like spaghetti, acorn, and Winter Luxury Pumpkin.
Cucurbita maxima- sweetmeat, hubbards, kabochas, kuri, buttercup, banana
Cucurbita moschata- butternut, baby butternut
Save the seed from summer squash when they are large and turning yellow. You shouldn't be able to dig your finger nails into the flesh. Harvest the winter squash when they are ready to eat and save the seed as you eat them in the winter.
Here I am cutting open baby butternuts for seed at a workshop.
On a home seed saving level just put the seed in a colander, rinse off the gunk and dry on a ceramic plate or screen. Be sure the seeds are completely dry before storing in an air tight container.