Garden watering calculator
Otter turns a five-day weather forecast into a watering decision by comparing forecast rain with the water an established garden is likely to need.
How the estimate works
The free estimate starts from a clearly labelled default: an established mixed garden border. Otter compares five days of forecast rainfall with an estimated water need based on the temperature-driven drying in the same five days.
The result is expressed as a percentage of the need that rain is expected to cover, with the forecast rain and estimated remaining need shown in millimetres.
- established beds and borders (the default)
- lawn
- vegetable garden
- pots and hanging baskets
- newly planted beds
- new trees and shrubs
Why the answer is a range, not a single number
A lawn, a border, a hanging basket and a new tree all need different amounts of water. Where the model cannot justify a single precise percentage, Otter shows a range and states the confidence behind it, rather than inventing precision.
Check the official restriction for your area. A Temporary Use Ban can change what you are allowed to do with a hosepipe, whatever this guidance says. Check your postcode.