Learn how to grow squash, and save squash seeds. This is a basic guide that will be added on to over time. For notes about the varieties we sell, scroll down to this section.
All squash varieties are warm season plants appropriate in zones 2-12.
How to Grow Squash
Sow seeds about 1 inch (2cm) deep.
Direct seed or transplant your squash in May or June, when soil is warm. Optimal soil temperature for germination: 25-35°C (68-95°F). Plant in a full-sun location.
If direct seeding, plant several seeds in the same location and thin to the best plant after they sprout.
Seeds sprout in 7-14 days.
If transplanting, you can start plants in late April or early May for transplanting about 3-4 weeks later when temperatures are high enough. When transplanting, try to minimize root disruption.
Vining types: Plant in rows 5 feet apart. Space plants at least 3 feet apart in each row.
Bush types: Plant in rows 3 feet apart. Space plants at least 2 feet apart in each row.
Pests and Diseases
Bacteria and fungal diseases are common in squash. Powdery mildew and wilt are two common diseases you may see, and are prevalent in hot and humid weather. Try watering earlier in the day so the leaves have time to dry off, avoid watering over top of leaves, or use drip irrigation. Remove diseased leaves when possible.
Pests might also cause issues, and are region dependent. You can remove insects by hand, remove debris, or select varieties that are most resistant to what you experience in your region.
How to save squash seeds
Isolate using blossom bags (or tape) and hand pollinate the squash flowers early in the morning. (Steps TBA).
Allow squash to fully mature on the vine. The skin should be tough (try to make a fingernail imprint – a mature squash skin will resist your fingernail imprint).
Harvest your best squash (with some vine on the stem), and allow the squash to cure outside in the sun, or a warm/dry environment, on a flat surface for 7-10 days rotating when possible.
Store the squash for at least a few more weeks in a cool and dark environment, up to several months.
Cut open the squash and remove all of the seeds. Compost the squash flesh (or if you’re adventurous, try fermenting or roasting and dehydrating it).
Place seeds in a large jar and add water to cover the seeds. Allow to ferment in a warm environment until you see some bubbling and a thin skin on top (this will take a few days).
Add some more water and skim off any fermentation goop, or tiny immature seeds floating at the top. Some varieties of squash will have seeds that float at the top that are immature or non-viable — but not all varieties! Some varieties will have floating seeds that are viable. Use your best visual judgement here, or see if you can find out online. If not sure you can always germination your seeds later on to learn what kind of squash variety you are working with.
Repeat this a few times until you mostly have viable seeds remaining.
Rinse the seeds well – the stringy bits of squash flesh should fall away from the seed during this process.
Place the seeds on a drying rack and use a fan or hairdryer (on low/no heat!) to remove any moisture as quickly as possible.
When dry to the touch, continue to allow the seeds to fully dry. If you can snap a seed in half (it cracks instead of bends), it is dry and ready to store in an airtight glass jar.
Place jar in a cool, dry, dark environment that has a consistent temperature. Average seed life is 4-6 years.
Notes on varieties we sell
The following section contains notes for the squash varieties we currently sell or have previously sold.
Homs Kousa: This is a vining, landrace variety.
Black Beauty Zucchini: This is a bush, heirloom variety.