5 Best Soil Moisture Meters

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Having an irrigation system is something that most people find convenient. You just cannot rely on the weather to give the exact amount of water your crops or plants need. You just set up the irrigation schedule, and the system does the rest.

It is very useful, especially in areas where the rainfall can be erratic. But what happens when you get good rainfall? When it is not really necessary to water your garden or crops. A standard irrigation system that is on a set schedule will run anyway.

And, while a little extra water is no big deal for most plants, drowning them with bucketfuls of extra water is only going to be a negative thing for them. It’s not so great for you either – water that you are paying for is wasted, and the nutrients in the ground are being leeched away.

But what is the alternative? There is no denying that being able to set up irrigation to an automatic timer is something that is extremely useful. If you have a large garden or a farm, it is one less thing on your to-do list.

And, most of the time, you do need some help in this department. However, during the rainy season, you are better served taking moisture readings and deciding whether or not to irrigate with these readings in mind.

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#1. The 3-in-1 Healthwiser Soil Testing Kit
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#2. The 3-in-1 pH Meter and Moisture Kit from Neewer

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#3. The Indoor/Outdoor Moisture Meter

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#4. The Moisture Meter from General Tools And Instruments

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#5. The Hydro Meter from Dr. Meter

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An Easier Way

That is where either a rain sensor or one of 5 best soil moisture meters that we have reviewed here will come in very handy. If you are a farmer and depending on where you live, the law may require that you have one of these already.

These are especially important in areas where water is scarce, and you may not be allowed to have an automatic irrigation system without one.

There are two basic choices here – you can either use a rain sensor or a soil moisture sensor.

Rain Sensors

Rain sensors tend to be a little less expensive to buy in the first place and can be easier to install. All you need to is find somewhere to attach it and leave it to stand fully exposed to the rain.

It is a useful item to have, but it might not be as accurate as you like. It measures all the rain that falls, even those light drizzles that hardly even make the ground underneath wet.

Soil Moisture Sensors

You can expect to pay a bit more for these and to install them means doing a bit of digging. The benefit here is that you get a more accurate read of the moisture that your plants have access to – i.e., the water that makes it down to the roots.

Also with this kind of sensor:

  • Recalibration is not required: Rain sensors entail more work to maintain them in proper working order. This means recalibrating them on a regular basis so that you can get the very best results out of them. It’s good to save the money initially, but is the small difference in price really worth the extra work at a later date? Soil sensors do not need to be recalibrated.
  • No need to replace certain parts: The rain sensor has a disk in it that expands when wet and contracts when dry. This will need to be replaced every so often in order to ensure that the system works as it should. A soil moisture sensor does not require the same amount of aftercare.
  • Better results: The soil sensor measures ground water. Now, if you have properly mulched the soil, it should still remain damp, even if you haven’t had rain in a few days. The rain sensor can only check for rain. So, if it decides that there has not been enough precipitation, it will turn on the sprinkler system. This can be wasteful if the ground is still damp.

The Best Position for Your Soil Moisture Monitor

This is going to depend on the space that you are monitoring. It would be a good idea to take readings in a few different areas within the garden.

If you have a sprinkler system, measure at both the extreme outer edge and also in the area that the bulk of the water flows.

Doing it this way ensures that you get the water to the plants as and when they actually need it. It will also help you determine what the optimal placement for your sprinkler system is.

If you want to perform something of a balancing act in your garden – like where you have a few dry patches and also wet patches, take various measurements, so you know exactly which areas need the most attention.

In some cases, like with the soil is sandy and drains quickly, it might be advisable to dig in some good compost to help the soil retain more moisture. With clay soil, you are bound to find that a lot more water is retained.

Strangely enough, the advice for clay soil is the same except that you need to put a little more work into it. You need to dig through the soil to loosen it up before adding in the compost. If it is really heavy clay, consider also adding in a little river sand as well.

More Water or Mulch?

This is not really about a moisture monitor, but I do think it deserves inclusion here. If your garden is patchy in areas, sometimes mulching it well is all that is needed to help even it out.

Mulching provides a barrier that prevents evaporation with the added bonus that it also stifles weeds. A good layer of mulch might be all that your garden needs.

Create your own mulch by allowing grass clippings or leaves to dry out or buy a ready-made mulch at your local gardening store.

There are many types of mulch to choose from. Hay is nice because it releases nutrients into the soil as it decays. Wood chips look a little nicer but should be avoided if you have a problem with ant in your garden.

If push comes to shove, use pebbles instead of an organic mulch. It can become a striking garden feature.

How to Use A Soil Moisture Monitor

Read through the manufacturer’s direction for the kit that you have. Most of the time, though, all you need to do is to push it down into the ground. If the soil is very hard, you may need to dig a small hole, put the monitor into it and then add back the soil.

The instructions will tell you how long it should be in the ground so that you can get an accurate reading. Generally, though, when the arrow on the dial stops moving up, it is done.

When you are done, take it out of the ground and wipe off any remaining dirt gently with a soft cloth. Cover it with a dry cloth and store in a cool area away from direct sunlight until you need to use it again.

Keeping Notes

It doesn’t take much effort to jot down what the readings were from place to place or plant to plant. It is especially helpful if you are finding it hard to get your plants to thrive outdoors.

All you need is a small notebook – record the date, time and whether or not it had rained recently. Keeping notes will help you to get everything perfect and also help you do better in the year ahead.

Readings should be taken at least once or twice a week, depending on the actual rainfall in your area.

When to take the readings is something that is often debated. Some people take them in the early morning, others in the early evening. Some believe that it is best to take them at midday. You should choose whatever time suits you best.

All you then need to do is to ensure that you take subsequent readings at the same time every day after that so that you get an accurate pattern of the water levels. While the probes should be extending into the lower levels of the soil, soil moisture can be affected throughout the day.

If it is hot, the moisture will dissipate faster, and so you will have less dampness in the soil. The key to overcoming differences related to climatic conditions is in always taking the readings at the same time every day.

Play with the Meter

I do encourage you to take it out and test it in a few different places, and at a few different times during the day. This will help you get the gist of measuring quickly and easily.

#1. The 3-in-1 pH Meter and Moisture Kit from Neewer

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This is a pretty impressive-looking gadget and also one of the newest entrants to the market. It has been cleverly designed so that it is sleek instead of bulky. You just stick it in the ground, and you can get a reading.

It does not require a battery or to be hooked up to electricity, and this is a huge plus.

Most users find it simple to use and pretty durable.

#2. The 3-in-1 Healthwiser Soil Testing Kit 

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This will let you monitor the pH of the soil, the light conditions and the moisture in the ground. For our purposes, the moisture meter is all that we need.

Again, this model is comfortably-designed and sturdy. It can be used either in the garden or in the home. It also does not require the use of batteries. The plus here is that it is lightweight enough to make carrying it a lot easier.

The dial is large enough to read comfortably.

#3. The Indoor/Outdoor Moisture Meter

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This ranks amongst the best for a good reason. It is durable, gives accurate results and is easy to manage. This is a machine made for one purpose and for one purpose only, to detect the amount of water in the soil.

It is a good buy for those who know they have the acidity levels in their soil right already but who want to improve the moisture content.

It is easy to use and easy to clean and has become a firm favorite with many gardeners.

#4. The Moisture Meter from General Tools And Instruments

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This one scores high points because it can be used indoors or out. It will let you know in next-to-no-time if there is a moisture problem in the home. It is also handy for establishing where you have groundwater issues in your garden.

It doubles up a leak detector so keep it on hand to check out damage after a flood.

The downside of this device is that it doesn’t look great. That said, the looks are of minor importance when you consider the overall functionality here.

#5. The Hydro Meter from Dr. Meter

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We have left this one until last because it comes up tops in our books. It consists of a simple design and an easy to read meter. The results produced are always accurate and keeping the machine in its optimal state is pretty easy.

All you need to do is to place the probes into the ground and take your reading.


If you are serious about gardening, or farming, making sure that your plants have the optimal water supply is an essential task to complete. While it may be easier to sit back and let the automatic irrigation system take over, you could find that this approach makes things harder.

If plants sit in water too long, they start to rot or, at the very least, become weaker. Too much water is just as bad as not enough for your plants. In this post, we ran through the myriad of options out there and chose the best five.

We rated the above options on durability, design, ease of use and accuracy. Choosing any of these five will help you to ensure that your plants stay healthy and happy for longer. If you want the best possible results, you have to work towards getting them.

With these little devices, though, your job has just become a whole lot easier.

My favorite is the 3-in-1 Healthwiser Soil Testing Kit for general garden use. It comes in at a good price and can be used to check pH as well.

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