Summer Squash Seeds,
Zucchini Caserta

Plant Caserta squash after the danger of frost has passed and soil has warmed to at least 70°F. In cooler climates, start seeds indoors 2–4 weeks before the last frost and transplant once the soil is consistently warm. If you’re not sure how to find your first and last frost dates, consult our blog post 'Our Experts Answer Questions, Share Resources.'

Direct sow Caserta squash seeds 1 inch deep in fertile, well-draining soil after the last frost. Space plants 24 to 36 inches apart in rows or hills to allow room for growth and airflow. In areas with short growing seasons, start seeds indoors under lights and harden off before transplanting. Don’t let them become rootbound; don't disturb roots while transplanting. Keep soil evenly moist during germination and early growth stages.

Maintain consistent soil moisture and feed plants with compost or organic fertilizer every few weeks to support vigorous growth. Caserta squash prefers warm weather and will flourish with 6–8 hours of sunlight daily. Use mulch to regulate soil temperature and retain moisture. Monitor for squash bugs and cucumber beetles, and remove them promptly to protect plants from damage and disease.

Note that there are four different species of squash: Cucurbita maxima, C. pepo, C. moschata, and C. mixta. They will not cross pollinate with each other, so it is possible to grow one of each species for seed saving without worrying about cross pollination. If you are planning to save seeds from several varieties of the same species, you can bag the blossoms and hand pollinate to avoid crossing.

• Allow fruit to fully mature on the vine until the skin becomes firm and dull.
• Harvest mature squash and cure for 2-3 weeks in a warm, dry area.
• Cut open and remove seeds and pulp.
• Rinse seeds to remove pulp and dry on a screen or paper towel in a well-ventilated area for 2–3 weeks.
• Store in a cool, dry place in a labeled envelope or airtight container.