Soil temperature in Indianapolis, Indiana
Soil temperature
89°F31.4°C
at 6cm — germination depth
Cooling over the next 11 days.
Too warm to seed — the soil is heat-stressed. Wait for it to cool.
Most cool-season lawns in the northern US and Canada are bluegrass, tall fescue, or a mix of the two. We assume that, and use12.5°C as the seeding threshold.
I know what grass I have
The differences are small. Ryegrass is the quickest off the mark; bluegrass is the slowest and wants the warmest soil. Everything else sits between.
| Species | Soil temp | Days |
|---|---|---|
| Perennial ryegrass | 8°C | 5–10 |
| Red / chewings fescue | 8–10°C | 10–14 |
| Tall fescuelikely yours | 10–12°C | 10–14 |
| Browntop bentColonial bentgrass | 10–12°C | 14–21 |
| Smooth-stalked meadow grassKentucky bluegrasslikely yours | 12–13°C | 14–28 |
Soil temperature at 6cm in Indianapolis, Indiana is currently 31.4°C, and falling about 28.2°C over the next 11 days. That depth matters because it is where grass seed sits and where roots start working, and it lags air temperature by days — which is why a warm afternoon here tells you very little on its own.
Lawns in this area are typically Kentucky bluegrass with tall fescue, the usual mix for cool-season lawns at this latitude. That blend needs the soil to hold above 12.5°C before seed germinates reliably. Too warm to seed — the soil is heat-stressed. Wait for it to cool.
7 of the next 10 days are good mowing days. The other 3 are held back by wet grass or soft ground. The best weekend slot right now is Monday 10am–3pm, on the basis that no rain since Saturday, ground firm.
The next recommended window in Indianapolis opens at 8am on Wednesday 2 September, because that is first light. Underfoot, the ground reads as firm after 9mm rain over the last week.
The next 10 days
Column height is how mowable the day is; the lighter band is the best stretch within it. The line is soil temperature at 6cm. It crosses the seeding threshold inside this forecast.
12.5°C — seeding
Soil at 6cm 31.4°C cooling to 0.0°C
Tuesday 1 September: Good. No — heat stress, 32°C.
Tuesday 1 SeptemberConfident
No — heat stress, 32°C.
- Good:Grass wetness
- Grass dryno rain since Wednesday
- Good:Ground firmness
- Ground firm9mm rain over the last week
- Marginal:Growth
- Growing slowlygrowth potential 0.30
- Poor:Temperature
- Heat stress32°C
- Good:Wind
- Wind light6 km/h
Limiting factor:temperature
Wednesday 2 September: Good. 8am–10am — barely growing — growth potential 0.20
Wednesday 2 September · 8am–10amConfident
8am–10am — barely growing — growth potential 0.20
- Good:Grass wetness
- Grass dryno rain since Wednesday
- Good:Ground firmness
- Ground firm9mm rain over the last week
- Poor:Growth
- Barely growinggrowth potential 0.20
- Poor:Temperature
- Cool24°C
- Good:Wind
- Wind light6 km/h
- Sociable hours
- A bit early or late, but finestarts at first light
Limiting factor:growth
Thursday 3 September: Good. 8am–10am — growing slowly — growth potential 0.22
Thursday 3 September · 8am–10amConfident
8am–10am — growing slowly — growth potential 0.22
- Good:Grass wetness
- Grass dryno rain in over a week
- Good:Ground firmness
- Ground firm9mm rain over the last week
- Poor:Growth
- Growing slowlygrowth potential 0.22
- Poor:Temperature
- Cool24°C
- Good:Wind
- Wind light6 km/h
- Sociable hours
- A bit early or late, but finestarts at first light
Limiting factor:growth
Friday 4 September: Good. 8am–10am — growing slowly — growth potential 0.21
Friday 4 September · 8am–10amConfident
8am–10am — growing slowly — growth potential 0.21
- Good:Grass wetness
- Grass dryno rain in over a week
- Good:Ground firmness
- Ground firm0mm rain over the last week
- Poor:Growth
- Growing slowlygrowth potential 0.21
- Poor:Temperature
- Cool25°C
- Good:Wind
- Wind light6 km/h
- Sociable hours
- A bit early or late, but finestarts at first light
Limiting factor:growth
Saturday 5 September: Good. midday–3pm — heat stress — 27°C
Saturday 5 September · midday–3pmReasonably confident
midday–3pm — heat stress — 27°C
- Poor:Grass wetness
- Grass drydried off since a shower 4 hours ago
- Good:Ground firmness
- Ground firm0mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.53
- Marginal:Temperature
- Temperature23°C
- Good:Wind
- Wind light6 km/h
- Sociable hours
- Fine by the neighboursstarts once the dew has burnt off
Limiting factor:temperature
Sunday 6 September: Good. 10am–9pm — rain earlier today, ground firm
Sunday 6 September · 10am–9pmReasonably confident
10am–9pm — rain earlier today, ground firm
- Good:Grass wetness
- Grass dryrain earlier today
- Good:Ground firmness
- Ground firm4mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.92
- Good:Temperature
- Temperature17°C
- Good:Wind
- Wind light9 km/h
- Sociable hours
- Fine by the neighboursstarts when it stops being antisocial
Limiting factor:none
Monday 7 September: Good. 10am–3pm — no rain since Saturday, ground firm
Monday 7 September · 10am–3pmReasonably confident
10am–3pm — no rain since Saturday, ground firm
- Good:Grass wetness
- Grass dryno rain since Saturday
- Good:Ground firmness
- Ground firm4mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.92
- Marginal:Temperature
- Temperature17°C
- Good:Wind
- Wind light5 km/h
- Sociable hours
- Fine by the neighboursstarts when it stops being antisocial
Limiting factor:none
Tuesday 8 September: Not worth it. No — 2.6mm of rain falling.
Tuesday 8 SeptemberReasonably confident
No — 2.6mm of rain falling.
- Poor:Grass wetness
- Grass wetraining now
- Good:Ground firmness
- Ground firm4mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.96
- Good:Temperature
- Temperature19°C
- Good:Wind
- Wind light8 km/h
Limiting factor:grass wetness
Wednesday 9 September: Not worth it. No — ground frozen.
Wednesday 9 SeptemberLow confidence this far out
No — ground frozen.
- Marginal:Grass wetness
- Grass drydried off since a shower 3 hours ago
- Good:Ground firmness
- Ground soft in places25mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.81
- Marginal:Temperature
- Temperature21°C
- Good:Wind
- Wind light12 km/h
Limiting factor:grass wetness
Thursday 10 September: Not worth it. No — ground frozen.
Thursday 10 SeptemberLow confidence this far out
No — ground frozen.
- Good:Grass wetness
- Grass drydried off since a shower 3 hours ago
- Good:Ground firmness
- Ground firm33mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.76
- Good:Temperature
- Temperature22°C
- Good:Wind
- Wind light13 km/h
Limiting factor:grass wetness
Nearby
Your own postcode
These are town-centre figures. Yours will differ a little.