When should squash be planted for optimal growth?
Written by
Benjamin Miller
Reviewed by
Prof. Charles Hartman, Ph.D.Plant squashes after all frost danger has passed and at the time when the soil is warming (65°F, 18°C) at a depth of four inches, as, for example, with the aid of a soil thermometer. A warm soil ensures rapid germination and healthy root development, while a cold soil will stunt plant growth and invite rot. Currently, there will be minimal loss of seedlings.
Summer Squash
- Direct sow 1-2 weeks after last spring frost
- Soil must maintain 65°F (18°C) consistently
- Plant every 3 weeks until midsummer
Winter Squash
- Start indoors 4 weeks before last frost
- Transplant when soil hits 70°F (21°C)
- Requires 90-120 frost-free days to maturity
Succession Strategy
- Begin new plantings every 21 days
- Stop summer types 12 weeks before first fall frost
- Final winter planting 100 days before frost
Use succession planting for continuous harvest throughout the growing season of your crops. I sow zucchini seeds every 3 weeks from early spring until midsummer, staggering their maturity and extending the productivity of each plant. Row covers protect late plantings from cool weather and predators. I harvest zucchini from June to October using this method.
For vining varieties, prepare planting mounds 3 ft. apart. Make the hills 12 in. high and 18 in. wide. Bush types need 2 ft. spacing in the row. Amend the soil with compost before sowing. Warm the soil faster with black plastic mulch. This helps stimulate earlier growth.
Check the soil temperature with a probe thermometer at 8 AM, and if the readings are low, cover the plants in beds and borders with cloches. Delays should be made in sowing in cold, wet springs. Where there is a rush, it compromises the quality of germination; waiting ensures the establishment of vitality.
Time your plantings to avoid the peak pest season. For example: Late plantings can help growers avoid the peak season for the pine borer cycle. All of this information should be tracked in a gardening journal. Each year you will review and modify your planting dates based on your harvest outcome. Timing your planting is critical to maximizing what you grow and minimizing any potential issues.
Read the full article: How to Grow Squash Successfully at Home
