Lawn care timed by soil temperature
Crabgrass, grass seed and fertilizer all respond to how warm the soil is. Measure it, enter it, and see what to do this week.
Soil temperature cheat sheet
- 50–55°F (0–2 in), warming: crabgrass pre-emergent window.
- 55–58°F at daybreak for 4–5 days: crabgrass starts germinating.
- About 70°F and up: warm-season seed can germinate.
- Late summer to early fall: best seeding time for cool-season lawns.
Sources and details in the planner.
How it works
1. Measure
Read soil temperature at the depth the research uses, early in the morning, for several days.
2. Match
Our planner compares it with extension thresholds for your grass type and season.
3. Measure the lawn
Calculators turn label rates into pounds of seed or fertilizer for your area.
Tools
ToolGrass seed calculatorPounds of seed for your area, by species, new lawn or overseeding.ToolFertilizer calculatorConvert N-P-K and a nitrogen rate into pounds of product and bags.ToolSoil temperature plannerEnter today's soil temperature and see which lawn jobs are due.ToolSprayer calibrationGallons per 1,000 sq ft, tank coverage and product per tank.
Timing guides
Timing guideCrabgrass pre-emergent timingThe 50–55°F window and why the date on the calendar misleads.Timing guideMeasuring soil temperatureDepth, time of day and spot choice for readings you can trust.Timing guideFertilizer scheduleFall-heavy for cool-season grass, summer for warm-season grass.Timing guideWhen to seed grassLate summer for cool-season, warm soil for warm-season grass.
New to the terms? Our glossary explains them in plain words.