Gardenplanner

Starting planned crops from seed indoors

Your saved crop plan and its researched timing determine the sowing window.

When we suggest this

  • Your noteYou selected this crop in your seed-starting plan. Its sowing window is open or starts within 14 days.
  • Climate averageAutomatic dates use the crop's researched calendar and local frost normals, with normal-night temperature adjustments where available. If you choose a transplant date, we count back using the crop's seedling lead time instead.

What would stop us suggesting it

  • When the sowing window ends, or you remove the crop or change its plan.
  • When you mark it Done or Doesn't apply. Automatic plans can remind you in the next researched season; a custom transplant date is for that date only.

What to do

  1. Aim to sow those plants between the start of your sowing window and its end; check the seed packet for variety-specific timing.
  2. Use clean containers with drainage and seed-starting mix. Follow the packet's sowing depth and label the seedlings.
  3. Keep the mix moist, let excess water drain, and provide enough light for sturdy growth.
  4. Gradually acclimate seedlings before moving them outside. Check the weather and soil before transplanting, then add them to your garden with their outdoor planting date.

What we can't know

  • Germination speed, variety, light and warmth can change when seedlings are ready.
  • A planned transplant date does not guarantee safe outdoor conditions.

Climate dates are averages. Custom dates are gardener choices; neither measures soil temperature or predicts the weather on planting day.

Where this advice applies

All US regions.

Choose crops in Garden. Use local climate dates or your own target transplant date.

Exceptions

  • Crops not selected in your seed-starting plan.
  • Dates outside the sowing window, or a reminder already completed or dismissed.
  • Automatic dates where there is no usable local frost calendar.

Related guide sections

Sources

  1. University of New Hampshire Cooperative Extension (K. Downing, O. Saunders). Growing Vegetables: When to Plant your Vegetable Garden. Accessed September 26, 2026
  2. University of Minnesota Extension. Starting seeds indoors. Accessed September 27, 2026

Reviewed

Sources checked Sept 2026 · awaiting expert review

Gardenplanner research (AI-assisted), pending extension-qualified review

Rule id and version: seed-starting.sow-indoors@1