Planning tool

Soil Temperature Germination Planner

Start with no-thermometer soil-warmth presets when an exact reading is not handy, then use catalog germination ranges as a go/no-go check before direct sowing outdoors, starting seeds indoors, or transplanting into cold beds.

Planning tool

Current soil warmth check

50F soil: cool-season seeds can start

33 catalog entries are in range at 50F; 70 need warmer beds before sowing or transplanting.

Soil reading50F
Ready now33 crops
Wait for warmth70 crops
Too warm0 crops

Default 50F readiness check

At 50F measured soil temperature, the catalog can start with a ready/wait split before users inspect every seed card.

Ready at 50F (33)

Wait for warmer soil (70)

Inputs

No thermometer presets
Start with cold spring bed, cool-season bed, mild spring bed, warm-season bed, or hot summer bed patterns before typing an exact 4-inch soil temperature.
Exact soil temperature reading
Optional fallback for gardeners with a soil thermometer; measure about 4 inches deep, then compare that reading with local frost risk and the seed catalog range.
Catalog germination range
Each seed entry stores a low and high germination temperature so cold-soil and hot-soil mismatches are visible before planting.
Start method
Direct sowing depends on outdoor soil warmth; indoor starts depend on warm growing medium before hardening and transplant timing.
Season and frost context
Cool-season entries tolerate colder starts better than warm-season entries, but frost risk and local forecasts still control outdoor planting.

What it returns

Planning guidance

Field reading
Use a soil thermometer placed about 4 inches deep, then compare the reading with the catalog range instead of planting by calendar date alone.
Minimum threshold
Plant when soils reach minimum temperature measured at 8 a.m., 4 inches deep; CSU notes beans are measured deeper than most entries.
Cool-season start
Early cool-season crops can use 40-50F soil when beds are workable, but check frost forecasts before treating cold tolerance as complete safety.
Moderate warmth
Moderately warm-season crops often establish better once soil reaches 55-60F, especially when roots need stronger early growth.
Warm-season wait
Heat-loving crops should wait for 65F or warmer soil and passed frost risk before outdoor planting.
Indoor-start caveat
Indoor trays need moist growing medium, steady warmth, and light after germination; a germination range is not a transplant date.

Regional soil-temperature fallback

Cool-soil candidates

Warm-soil candidates

Supporting planning paths

Source basis