Want Bigger Veggies and Hardier Flowers? A Botanist Says It Starts with the Soil, and a $9 Tool Can Fix It All

Unlike other pro gardening tips, you don’t need to invest in any expensive, fancy tech to use this one at home. Moisture meters can be inexpensive, and the one I recently tested has helped me rectify common soil mistakes like overwatering and underwatering—and it’s on sale for $9.

Craft911 GrowIt Plant Moisture Meter

Credit: Amazon

Now less than $10 thanks to the 40% discount, the popular soil moisture meter has a 7-inch probe and comes with a free plant-watering e-book that details light and moisture preferences of more than 200+ plant species. The design is also completely analog—no batteries required—and offers an instant, accurate read in seconds.

Still not convinced you need one in order to optimize your garden’s soil? Vukicevich cautions that even if you water plants regularly with a scheduled irrigation system, plants could still be at risk.“Depending on how you water—with drip or sprinklers, or hand watering—you may have wetting zones and drier patches, so you want to make sure [moisture meters] are placed in a spot that is representative of where roots are growing,” Vukicevich tells Better Homes & Gardens.

What to know about soil moisture and moisture meter use

Since I’m no soil scientist, I asked Vukicevich to break down the intricacies of soil moisture levels, textures, and types, and how gardeners can leverage this information.

“Soils with different textures hold different amounts of water. Soils with more clay hold more total water compared to sandy soils, which only hold a small amount,” Vukicevich explains. “Although clay can hold a ton of water, infiltration is slower and some of that water is held so tightly that plant roots cannot access it at all. Conversely, water infiltrates sandy loam soil relatively quickly but also drains out fairly quickly. So the actual water plants can use is held between these two points we call field capacity and permanent wilting point.”

Xlux Soil Meter Moisture Meter

Raintrip 4-in-1 Soil Moisture and pH Meter

That’s where the Craft911 GrowIt Plant Moisture Meter comes in. “A soil moisture meter will be most useful if you can understand how its readings relate to these two points for your particular soil,” Vukicevich says. “Field capacity happens after a soil drains (think: after a big rain) and then holds water against gravity, [which is] when plants start drinking.” By comparison, “permanent wilting point happens when water gets so low (from plants drinking and evaporation) that plants can’t get enough water anymore.”

How soil moisture affects plant health, growth, and yield

How much moisture your soil has in its metaphorical tank directly affects the health of your plants.

“Plants need water in order to photosynthesize,” Vukicevich explains. “If soil moisture is very low, plants can become stressed and will likely not grow as well.” However, too much moisture is equally detrimental. “Saturated soil, which can last longer than it has to if you have very dense, compacted soil, creates a low oxygen environment, which most plant roots do not tolerate well since they need to respire like you and me.”

The latter could result in near-fatal problems like root rot, yellowing levels, and lack of growth. It can also kill off plants entirely.

Censinda Soil Moisture Meter

Gouven Soil Moisture Meter

How to measure with a moisture meter correctly

According to Vukicevich, there are many kinds of soil moisture meters, but the type of moisture meter is not as important as using it correctly.

“No matter which kind of meter you are using, it will be important to take readings at different moisture levels—right after a thorough irrigation, a day after, [and then] when you see plants becoming stressed—so you can calibrate the readings to your soil,” Vukicevich says. “After calibrating a moisture meter to what you can see and feel with your own hands, it can be a useful tool to help you know what is going on below the surface and how long before you need to water again.”

To use Craft911 moisture meter in particular, the directions recommend inserting the meter 3 to 4 inches deep. If the scale reads under three, it likely needs water; if the moisture registers as more than a nine, refrain from watering until the number drops between the four to nine range.

“Remember that as the summer heat comes plants will take up a lot more water and you will also lose more to evaporation,” Vukicevich adds. “Using compost and mulch can help minimize water loss to evaporation and increase water use efficiency.”

The Craft911 GrowIt Plant Moisture Meter is an analog solution to the age-old problems of overwatering and underwatering. Now that we know just how much the soil and its moisture content impacts plant health, we think adding this hack is a worthwhile investment for better blooms and harvest. Get it now while it’s on sale at Amazon for just $9.