Garden Water Needs Calculator
Find out exactly how much water your garden needs each week and how long to run your hose or sprinkler.
Results
Visualization
How It Works
Most vegetable gardens need about 1 inch of water per week, which equals roughly 0.623 gallons per square foot. Consistent, deep watering beats frequent light sprinkling every time.
The Formula
Gallons = Area (sq ft) x Inches Needed x 0.623
Variables
- 0.623 — gallons of water in 1 inch of depth over 1 square foot
- 1 inch/week — standard recommendation for most vegetables and established lawns
Tips
- Water deeply 2-3 times per week rather than lightly every day — deep watering encourages deeper root growth.
- Water in the early morning (before 10 AM) to reduce evaporation and give leaves time to dry, which helps prevent fungal diseases.
- A rain gauge is a cheap and invaluable tool — place one in your garden to know exactly how much rain you are actually getting.
- Mulch around your plants reduces water needs by 25-50% by slowing evaporation from the soil surface.
- Drip irrigation or soaker hoses deliver water right to the roots where it is needed, wasting far less than overhead sprinklers.