Planning tool

Seed-Starting Tray Planner

Estimate tray counts, filled cells, open cells, and the first indoor-start batch from selected crop bed fit, tray size, optional manual cell edits, and last frost date.

Inputs

Selected crop bed-fit default

On seed detail routes, start Plants each from the selected crop spacing and current bed size before asking users to edit tray counts.

Common tray-size presets

Start with 50-cell, 72-cell, 128-cell, or 200-cell trays before entering a custom count.

Exact tray cell count

Keep an exact cells-per-tray field available for custom inserts, half trays, or mixed tray setups.

Manual cells-per-crop editing

Keep the cells-per-crop field available for over-seeding, backup starts, or non-bed tray targets.

Last frost date

Converts weeks-before-frost guidance into calendar dates after the tray size and plant-count starting point are set.

Cells per crop

Applies a consistent planning allowance to each crop in the current filtered list.

Bed-fit shortcut

Uses the selected crop spacing and current bed size to set plants per variety without separate spacing math.

What it returns

• Indoor-start varieties that match the active catalog filters.
• Tray count, filled cells, and open cells for the selected tray size.
• Earliest seed-starting batch and estimated transplant timing.
• Internal links to local timing, hardening-off, and germination troubleshooting paths.

Regional seed-starting timing fallback

• Regional Planting Guides Use regional guides to check local last-frost assumptions before sizing indoor-start trays; 111 source-backed regional guides cover All 50 U.S. states.
• Planting Calendar Tool Convert weeks-before-frost indoor-start windows into dated tray batches
• USDA Zone and Frost-Date Planner Keep hardiness zones separate from annual last-frost seed-starting inputs

Indoor-start planning paths

• Start Indoors Seeds 50 indoor-start varieties
• Seed-Starting Planner 50 indoor-start varieties
• Seed Germination Troubleshooting Planner Troubleshoot damping-off, dry media, and slow germination before filling more trays
• Transplant Garden Planner 50 transplant-capable varieties
• Hardening-Off Transplant Planner Plan the outdoor transition before indoor-start trays outgrow protected space
• Vegetable Catalog Food crops with spacing and maturity data
• Container-Friendly Seeds Compact crops for smaller starts
• Container Garden Planner 72 container-ready varieties

Early tray candidates

• Delicata Winter Squash 3 weeks before last frost
• Hale's Best Jumbo Melon 3 weeks before last frost
• Marketmore 76 Cucumber 3 weeks before last frost
• Small Sugar Pumpkin 3 weeks before last frost
• Sugar Baby Watermelon 3 weeks before last frost
• Waltham Butternut Squash 3 weeks before last frost

Source basis

• UMN starting seeds indoors Indoor seed-starting timing and transplant reference
• UMN planting the vegetable garden Outdoor timing reference for transplant windows
• Penn State cole crops for home vegetable gardens Cool-season transplant crop reference