When scorching temperatures hit, keeping your garden hydrated can be a real challenge. Overwatering wastes precious resources, while underwatering can stress your plants and stunt growth. One surprisingly simple gardening trick gaining attention is placing a shallow pan of water on your lawn or garden to monitor evaporation — a practical way to gauge how much water your plants actually need during hot weather.

How Does the Pan of Water Trick Work?

Experienced gardeners swear by this method. Here’s why: placing a pan of water outside lets you visually track how much moisture evaporates from a known quantity of water over a set period. Since evaporation rates closely mirror how much moisture your soil and plants are losing, this gives you a practical reference point to adjust your watering schedule.

How Long Should You Monitor Evaporation?

For best results, place the pan in a representative spot in your garden — ideally in the sun and away from shelter — and check it daily for 3 to 5 days. Measuring the drop in water level each day helps you understand how much water is evaporating under current weather conditions, factoring in heat, wind, and humidity.

Why Is Knowing Evaporation Important?

Soil moisture loss from evaporation is a key factor in plant health. If you water without considering evaporation, you risk either flooding roots (leading to rot) or letting plants dry out. By estimating evaporation, you can better time your watering sessions and the volume of water needed, conserving water while keeping plants healthy and thriving. 

Expert Tips for Watering During Hot Weather

• Water Early or Late: Avoid watering during peak heat to minimize evaporation loss. Early mornings or evenings are ideal.

• Use Mulch: Mulching helps retain soil moisture by reducing surface evaporation and moderating soil temperature.

• Deep Watering: Water deeply but less frequently to encourage roots to grow deeper and plants to better withstand drought.

• Group Plants by Water Needs: Cluster plants with similar moisture requirements to water efficiently without waste.

• Check Soil Moisture: Besides the pan method, use your finger or a soil moisture meter to check the soil before watering.  

Conclusion

Using a pan of water to monitor evaporation is a low-tech, easy method that gardeners can use to fine-tune watering during hot spells. Paired with smart watering habits, it helps conserve water, promotes healthy plants, and ensures your garden weathers the heatwave with grace.

If you’re facing a heatwave, give this simple tip a try — your plants will thank you!