Measuring Rainfall in the Garden

Don’t just rely on local weather reports

Use a rain gauge for accurate rainfall readings

It’s several weeks into hurricane season on the Gulf Coast, and we know that even if we’re hundreds of miles away from where a hurricane makes landfall, we can still feel its effects by the rainclouds that move in and pour upon our yards. People have always had an interest in how much rain has fallen, especially gardeners, because the rate of precipitation has a lot to do with the success or failure of whatever we might be growing. 

Back in the 13th century, the first concept of what we would now call a rain gauge was invented. It’s become one of the easiest and most reliable methods for measuring rainfall, and it’s a very helpful garden tool. 

What’s a rain gauge?

It can be called an ombrometer, a pluviometer, or udometer. Say either one of those names three times fast! Generally, it’s a gauge that measures rain precipitation through a predetermined time period per unit area. In the U.S., rain is measured only in inches, and although it might be hard to conceptualize rain in terms of inches, you can easily see that an inch of rainfall in a week is a lot less than the same amount in an hour. And how much is an inch of rain, really? It’s enough to cover flat ground entirely, and it’s the equivalent of 4.7 gallons of water per square yard. 

Rain gauges are great to help drought-stressed plants, or overwatered areas which could contribute to many other issues. Remember, overwatering is costly, and it promotes shallow roots and could make your yard susceptible to many diseases. 

Rain gauges are important, and here’s why:

• You can anticipate floods or sudden climate changes.
• You will see if your plants or crops are being overwatered or not watered enough.
• Tracking your rainfall will help you estimate when you’ll be able to harvest your produce.

Types of rain gauges

Standard: This is a straightforward design used by nearly every organization that measures rainfall and consists of a measuring tube that collects the rain as it falls. You can simply measure it by checking the number of inches that it has collected. 

Tipping bucket: This rain gauge is more comprehensive, so the measurement it takes is a bit more accurate. Its design is simple—a receiving funnel collects the rainfall and transfers it into a second bucket. The tipping bucket design delivers the data more accurately than the standard one. The funnel gauge collects rain as it’s falling, and transfers it through a funnel to other buckets, where it’s possible to measure the depths of the rainfall. 

Weighing gauge: This is a single bucket used as a storage bin to measure the rainfall. With a weighing mechanism, it measures rainfall intensity by measuring the total rainfall in terms of time and depth, at once. 

More than just for measuring rain

The amount of water your yard or plants need will vary according to the season and your landscape, but most plants require at least weekly watering. A garden rain gauge can even track your sprinkler’s output, which is not only helpful to the plants, but could lower your water bill. 

For your lawn and garden, 1-2 inches of water per week is what’s recommended. Just be sure your rain gauge is in the path of the area being watered, and after the sprinkler has run about 30 minutes, measure the depth on the gauge, and multiply by two to figure out how much water it would get over an hour. Continue monitoring and ensure your flow rate isn’t contributing to runoff. Record your data. 

A rain gauge can measure rain, but also dew and mist as well. Just place the gauge in an open area, far from the house, trees, swimming pools, or other buildings you might have on your property. Be sure to empty it after each rain. This is the only way to really be sure how much precipitation is in your garden, and then you can manage your water, cut costs, and conserve water.

Pro tips:

• Know your soil. Gardeners should know whether water penetrates the soil well, and if it can hold water. Is your soil more clay, or sandy or loamy? You can’t always tell if your garden is wet—after a rain, put your finger into the ground. You might be surprised to find dry soil. The type of soil you have also affects the kind of compost you might consider using. 
• Select plants that will grow and thrive in the climate you’re in, and specifically, in the conditions of your garden. Consider the areas of direct or partial sun, or shade, and plant accordingly. Get to know your native plants because they’ll almost always do well, and if you’re in a very dry area, find drought-tolerant plants that will flourish in your yard.