If you want to keep your squash seed pure (that is, not a hybrid of two varieties) it may help to hand pollinate your female flowers. This is because squashes have a very long isolation distance of 1/4 mile.
So, if you LOVE that golden zucchini you grew last year and your wife is begging you to plant more (and you know your neighbor grows Dark Star zucchini) then you should consider hand pollinating your squash to be able to keep your seeds for next year!
Don’t panic. Here is how you do it.
Squash flowers come in 2 varieties: Male and Female. They are easy to tell apart. Male flowers have a very long skinny base like a drinking straw. Female flowers have the start of a plump little zucchini fruit at the base.
Timing is very important. You need to be aware of when the female flowers are budding and be available the morning they choose to open. You do not want other pollinators like bees, wasps, or butterflies getting to your female flowers first.
In the early morning, scope out your squash situation. If female flowers have already opened and you know you only want pure seed, cut them off the plant at the base and ENJOY the succulent, pubescent, and sweet flowers and fruit. They make amazing egg scrambles.
At this time, also cut off male flowers at the base. Do a fire drill, rodeo, square dance with these male flowers. Stage them at OTHER zucchini plants with female flowers that are just about to open for the first time. Mix it up. Keep the genetics guessing.
When you have several male flowers staged at female flowers, the fun begins. Take each male flower and peel the petals open to reveal the fertile pollen grains inside.
Place this magic wand (stamen) of the next generation inside the intricate folds of the lady flower (stigmas), being sure to contact all sides of the stigmas with pollen. Repeat with all male flowers available for that female flower.
Tape this female flower closed. I like to also mark the base of the successfully-pollinated budding zucchini fruit with a rubber band to make sure I know which fruits will produce pure seed.
Please be sure to eat all parts of the male flower after they are used. They are so sweet and healthful. You will be missing out if you don’t. And give thanks.