🌿 Garden & Allotment Advisory
Frost risk, watering needs and soil temperature for the next 8 days • Last checked: 12:07 on Thursday 5 November 2026
Three real questions for the plot or allotment, answered fresh every day: is anything at risk of frost overnight, does the ground need a drink or will the rain see to it, and is the soil actually warm enough yet for what you're hoping to sow. For the theory behind the watering numbers below, see the Evapotranspiration page; for typical/average frost dates rather than this week's actual forecast, see the Frost & Growing Season Calculator.
Today
Thursday 5 Nov
❄ Overnight low
8°C
No frost risk
💧 Water balance
-1.1mm
Borderline - check pots and containers
🌱 Soil 10.5°C — Most vegetables can go in
Worth a check
Borderline - check pots and containers.
Tomorrow
Friday 6 Nov
❄ Overnight low
8.9°C
No frost risk
💧 Water balance
+0.6mm
Borderline - check pots and containers
🌱 Soil 10.3°C — Most vegetables can go in
Worth a check
Borderline - check pots and containers.
Sat 7 Nov
Saturday
❄ Overnight low
6.3°C
No frost risk
💧 Water balance
+0mm
Borderline - check pots and containers
🌱 Soil 10°C — Most vegetables can go in
Worth a check
Borderline - check pots and containers.
Sun 8 Nov
Sunday
❄ Overnight low
5.6°C
No frost risk
💧 Water balance
-0.6mm
Borderline - check pots and containers
🌱 Soil 9.8°C — Hardy seeds only (broad beans, peas, spinach)
Worth a check
Borderline - check pots and containers.
Mon 9 Nov
Monday
❄ Overnight low
7.3°C
No frost risk
💧 Water balance
-0.8mm
Borderline - check pots and containers
🌱 Soil 9.1°C — Hardy seeds only (broad beans, peas, spinach)
Worth a check
Borderline - check pots and containers.
Tue 10 Nov
Tuesday
❄ Overnight low
10°C
No frost risk
💧 Water balance
+1.7mm
No need to water - rainfall should cover it
🌱 Soil 9.4°C — Hardy seeds only (broad beans, peas, spinach)
Good gardening conditions
No special precautions needed - crack on with whatever's on the list.
Wed 11 Nov
Wednesday
❄ Overnight low
12.9°C
No frost risk
💧 Water balance
+0.2mm
Borderline - check pots and containers
🌱 Soil 10.9°C — Most vegetables can go in
Worth a check
Borderline - check pots and containers.
Thu 12 Nov
Thursday
❄ Overnight low
11.3°C
No frost risk
💧 Water balance
+12.1mm
No need to water - rainfall should cover it
🌱 Soil 11.5°C — Most vegetables can go in
Good gardening conditions
Steady as she goes - nothing forecast to change your plans.
Overnight low vs soil temperature, and daily water balance
About this data
Soil temperature is Open-Meteo's own 6cm-depth forecast reading (a real root-zone figure, not estimated from air temperature) - the sowing bands above follow widely-used UK gardening guidance rather than a strict scientific threshold, so treat them as a helpful guide rather than a hard rule, especially for slightly more or less hardy varieties.
Water balance compares forecast rainfall against Open-Meteo's own FAO-56 reference evapotranspiration figure (ET₀) - the same standard calculation explained in detail on the Evapotranspiration page. A positive number means more rain is expected than the ground is likely to lose to evaporation and plant use; a negative number means the reverse. Containers and hanging baskets dry out faster than open ground and may need watering even on a borderline day.
Overnight low temperature comes straight from Open-Meteo's forecast for Southampton, checked every 30 minutes. For average first/last frost dates from the historical record rather than this week's forecast, see the Frost & Growing Season Calculator.
See also: Evapotranspiration • Frost & Growing Season Calculator • Dog Walking Weather Advisory