Why schedule irrigation by weather?
Plants use water faster on hot, dry, windy days and slower on cool, humid or cloudy ones. Rain adds water for free. A fixed schedule wastes water after a rainy week and shorts plants during a heat wave.
Basing watering on conditions can reduce water and energy use, lower disease risk from overly wet foliage and improve plant health. It also helps with costs if you pump from a well or buy water.
If you irrigate from a pond, well or stream, remember that supply matters too. Keeping a record of how much water you actually pump helps you spot problems with equipment and plan around limited sources.
What weather information matters most?
Rainfall, temperature, humidity, wind and sunshine all affect how much water plants lose. Rainfall you measure yourself is especially valuable because storms are patchy. Add a look at the forecast so you can skip watering when meaningful rain is coming.
Some public tools estimate crop water use from weather data for your region. Ask your state Extension service which tools exist locally and how to use them, because crop factors and methods vary.
If you are unsure which tool to trust, compare its estimates with your own soil checks for a few weeks. Where they disagree, believe the soil in front of you and adjust the tool.
- Rain gauge on your own land
- Daily temperature and wind
- Forecast for the next few days
- Regional crop water use tools from Extension
How do I check the soil?
Weather estimates should be matched with soil checks. Dig a small hole and feel the soil at root depth. Sandy soils dry quickly and need more frequent, lighter watering, while clay holds water longer and can become waterlogged.
Soil moisture sensors can help, but a trowel and your hands also work. Learn what moist but not soggy feels like for your soil. Your NRCS service center or Extension office can help identify your soil type.
Mulch reduces evaporation from the soil surface and moderates soil temperature, so it can cut watering needs. Keep mulch pulled back from stems to avoid rot.
How much and how often should I water?
Deep, less frequent watering generally encourages deeper roots than shallow, frequent watering, though the best approach depends on the crop, soil and system. I will not give you specific amounts, because they depend on plant stage, climate and equipment.
Look for published guidance from your state Extension service for your crop. Then calibrate your own system: measure how much water it actually delivers in a set time, using catch cans or a gauge, so you can apply the amount you intend.
What common mistakes should I avoid?
Watering in the heat of the day loses more to evaporation. Watering late in the evening can leave foliage wet overnight and encourage disease in some crops. Leaky lines, clogged emitters and uneven pressure waste water and cause patchy growth.
Another mistake is forgetting to adjust. Review your schedule weekly in the growing season, and turn systems off for rain. Rain sensors and controllers can help, but check that they work.
Check connections and filters at the start of each season. A small leak running for weeks wastes more water than most people expect, and the damage to the crop may not show until the plants are stressed.
How do water rules and drought change things?
During drought, water use may be limited by your water provider, irrigation district or state. Well owners should also watch for falling water levels. Rules vary by place and can change quickly, so check with the official body that applies to you.
Drought.gov and your state drought office publish current conditions. Ask Extension about drought-tolerant crop choices, mulching and other ways to stretch limited water.
How do I keep a simple irrigation log?
Write down the date, how long each zone ran, the rain since the last watering and a quick note on how plants and soil looked. Add any repairs.
After a season, compare the log with your yield and plant health. You will see whether you tended to overwater or underwater, and which zones always dry first.
Share the log with your Extension agent if you want help refining it. A record of what you actually did is more useful than memory.
- Date and run time
- Rain since last watering
- Plant and soil condition
- Repairs and changes
Key takeaways
- Water according to weather and soil, not just the clock.
- Measure your own rainfall and check soil at root depth.
- Calibrate your system so you know what it delivers.
- Check local water rules and drought conditions with official sources.
Sources and further reading
Last reviewed: November 12, 2026. Written by the Rural Farm Life Editorial Team. See our editorial policy.