Soil temperature in Trenton, New Jersey
Soil temperature
79°F26.2°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 Trenton, New Jersey is currently 26.2°C, and falling about 24.7°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 best weekend slot right now is Monday 10am–8pm, on the basis that no rain since Friday, ground soft in places.
The next recommended window in Trenton opens at 8am on Thursday 3 September, because that is when the dew has burnt off — earlier than that and you are cutting wet grass. Underfoot, the ground reads as firm after 27mm 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 25.3°C cooling to 0.0°C
Tuesday 1 September: Not worth it. No — 2.2mm of rain falling.
Tuesday 1 SeptemberConfident
No — 2.2mm of rain falling.
- Poor:Grass wetness
- Grass dryrain earlier today
- Good:Ground firmness
- Ground firm27mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.66
- Good:Temperature
- Temperature23°C
- Good:Wind
- Wind light5 km/h
Limiting factor:temperature
Wednesday 2 September: Good. No — grass wet, rain earlier today.
Wednesday 2 SeptemberConfident
No — grass wet, rain earlier today.
- Poor:Grass wetness
- Grass wetrain earlier today
- Good:Ground firmness
- Ground firm28mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.92
- Good:Temperature
- Temperature20°C
- Good:Wind
- Wind light10 km/h
Limiting factor:grass wetness
Thursday 3 September: Good. 8am–2pm — grass dry — no rain since Tuesday
Thursday 3 September · 8am–2pmConfident
8am–2pm — grass dry — no rain since Tuesday
- Good:Grass wetness
- Grass dryno rain since Tuesday
- Good:Ground firmness
- Ground firm40mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.68
- Poor:Temperature
- Temperature21°C
- Good:Wind
- Wind light6 km/h
- Sociable hours
- A bit early or late, but finestarts once the dew has burnt off
Limiting factor:grass wetness
Friday 4 September: Good. No — 0.3mm of rain falling.
Friday 4 SeptemberConfident
No — 0.3mm of rain falling.
- Marginal:Grass wetness
- Grass drydried off since a shower 4 hours ago
- Marginal:Ground firmness
- Ground soft in places21mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.52
- Poor:Temperature
- Temperature23°C
- Good:Wind
- Wind light4 km/h
Limiting factor:ground firmness
Saturday 5 September: Good. 9am–8pm — ground soft — 51mm rain over the last week
Saturday 5 September · 9am–8pmReasonably confident
9am–8pm — ground soft — 51mm rain over the last week
- Good:Grass wetness
- Grass dryrain earlier today
- Marginal:Ground firmness
- Ground soft51mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.97
- Good:Temperature
- Temperature17°C
- Good:Wind
- Wind light16 km/h
- Sociable hours
- A bit early or late, but finestarts once the dew has burnt off
Limiting factor:ground firmness
Sunday 6 September: Good. 10am–8pm — ground soft in places — 67mm rain over the last week
Sunday 6 September · 10am–8pmReasonably confident
10am–8pm — ground soft in places — 67mm rain over the last week
- Good:Grass wetness
- Grass dryno rain since Friday
- Marginal:Ground firmness
- Ground soft in places67mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.97
- Good:Temperature
- Temperature14°C
- Good:Wind
- Wind light9 km/h
- Sociable hours
- Fine by the neighboursstarts when it stops being antisocial
Limiting factor:ground firmness
Monday 7 September: Good. 10am–8pm — no rain since Friday, ground soft in places
Monday 7 September · 10am–8pmReasonably confident
10am–8pm — no rain since Friday, ground soft in places
- Good:Grass wetness
- Grass dryno rain since Friday
- Good:Ground firmness
- Ground soft in places59mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.97
- Marginal:Temperature
- Temperature16°C
- Good:Wind
- Wind light5 km/h
- Sociable hours
- Fine by the neighboursstarts when it stops being antisocial
Limiting factor:none
Tuesday 8 September: Good. 8am–3pm — no rain since Friday, ground firm
Tuesday 8 September · 8am–3pmReasonably confident
8am–3pm — no rain since Friday, ground firm
- Good:Grass wetness
- Grass dryno rain since Friday
- Good:Ground firmness
- Ground firm59mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.88
- Marginal:Temperature
- Temperature19°C
- Good:Wind
- Wind light7 km/h
- Sociable hours
- A bit early or late, but finestarts when it stops being antisocial
Limiting factor:none
Wednesday 9 September: Not worth it. No — ground frozen.
Wednesday 9 SeptemberLow confidence this far out
No — ground frozen.
- Marginal:Grass wetness
- Grass dryno rain since Friday
- Good:Ground firmness
- Ground firm58mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.89
- Good:Temperature
- Temperature19°C
- Good:Wind
- Wind light10 km/h
Limiting factor:none
Thursday 10 September: Not worth it. No — ground frozen.
Thursday 10 SeptemberLow confidence this far out
No — ground frozen.
- Poor:Grass wetness
- Grass drydried off since a shower 2 hours ago
- Good:Ground firmness
- Ground soft in places51mm rain over the last week
- Good:Growth
- Growing wellgrowth potential 0.83
- Marginal:Temperature
- Temperature21°C
- Good:Wind
- Wind light11 km/h
Limiting factor:grass wetness
Nearby
Your own postcode
These are town-centre figures. Yours will differ a little.