How to Start Squash Seeds

Fast-growing summer and winter squash - from seed to harvest in weeks!

4-7
Days to Germinate
2-4
Weeks Before Transplant
70-95°F
Germination Temp
1"
Planting Depth

Don't Start Too Early!

Squash grows incredibly fast and hates being rootbound. Start only 2-4 weeks before transplanting, and use large pots or peat pots. Rootbound squash seedlings often fail after transplanting.

Step-by-Step Guide

1

Use Large Pots

Start in 3-4" peat pots or soil blocks. Squash grows fast and needs room! Small cells cause problems. Use moist seed starting mix.

2

Plant Seeds

Plant 1-2 seeds per pot, 1 inch deep, pointed end down. Cover and water gently. Large seeds are easy to handle!

3

Provide Heat

Use a heat mat at 80-90°F for fastest germination (4-5 days). Without heat, germination takes 7-10 days and may be spotty.

4

Add Light

Once sprouted, remove from heat mat and provide 12-14 hours of strong light. Squash grows fast and needs lots of light to stay compact.

5

Thin to One

If both seeds sprout, snip the weaker one at soil level. Don't pull - you'll disturb the roots of the keeper.

6

Harden Off & Transplant

Harden off for 5-7 days, then transplant when seedlings have 2-3 true leaves. Plant the entire peat pot - squash hates root disturbance!

Summer vs Winter Squash

Summer Squash

Zucchini, yellow squash, pattypan

  • • Harvest immature (soft skin)
  • • 45-65 days to harvest
  • • Eat fresh, don't store long
  • • Very productive!

Winter Squash

Butternut, acorn, spaghetti squash

  • • Harvest mature (hard skin)
  • • 80-120 days to harvest
  • • Stores for months
  • • Needs more space

Frequently Asked Questions

When should I start squash seeds indoors?

Start squash only 2-4 weeks before your transplant date (which is 1-2 weeks after last frost). Squash grows extremely fast and becomes rootbound quickly. Don't start too early!

Should I direct sow or transplant squash?

Direct sowing works well if your season is long enough. Transplanting gives a 2-3 week head start in short-season areas. Use peat pots to minimize transplant shock - squash hates root disturbance.

What temperature do squash seeds need?

Squash seeds germinate best at 70-95°F (optimal 85-90°F). They germinate quickly (4-7 days) in warm soil. Below 60°F, germination is poor or fails. Use a heat mat for best results.

Which way up do I plant squash seeds?

Plant squash seeds pointed end down, about 1 inch deep. The pointed end is where the root emerges. If unsure, plant flat - the seedling will figure it out.

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