The 10 Best Compost Thermometers – [Reviews & Rankings]

A compost thermometer, also known as a compost temperature gauge, is a thermometer used to measure the temperature levels of a compost heap. The best compost thermometer will be accurate, durable, have a hermetically sealed dial, and will be easy to read.

If you are looking to increase your compost quality, you should consider getting a compost thermometer. These devices come in handy and help you understand and moderate the state of your compost pile (Source).

A compost thermometer is required for hot composting. The more heat there is, the faster your materials will break down. But you don’t want your compost to get too hot, because it will dry it out, which will inhibit the composting process.

Hot composting is simple. Use a mix of brown (carbon-rich material), and green (nitrogen-rich material), and make a pile by layering the two materials, one on top of the other. Once you do that, all you have to do is add water. As the microorganisms start to do their thing, the temperature of the compost pile will increase. The trick is to not let your pile get any hotter than 140 degrees (Source).

A compost thermometer is an essential tool for hot composting, and you want it to be accurate.  Before you buy a compost thermometer, consider its price, build quality and accuracy. You should also consider its temperature range.

In this article, we will examine all the top-rated compost thermometers. All of the compost thermometers in this review will accurately report the temperature of your pile, whether you are an experienced composter, or you’re just now getting into the trend.

What Is A Compost Thermometer?

As the name suggests, this is typically a thermometer used to measure the temperature levels of the middle-section of any compost heap. To achieve this, its probe ought to be quite long, with the standard length being 20 inches. This enables the sensitive part of the thermometer to reach the center.

Additionally, it ought to withstand moisture as well as expected creepy crawlies in the heap. If you are new to this, temperature readings are used to indicate when to turn the pile. It also allows the operator to monitor and maintain high temperatures for a long period, enough for diseases and weeds buried in the heap to die.

With that understanding, it is of immense importance that you settle for the best compost thermometer. A good product, as mentioned, should be of appropriate length, clear and easy to read, has a wide temperature range, made of stainless steel to avoid rusts, and come with a warranty.

Do You Need a Compost Thermometer?

Anyone who practices hot composting needs to have a Compost Thermometer. While composting works best in hot conditions, if compost is too hot it can dry out and compromise your composting quality. To accurately monitor even the deepest layers of your compost, a Compost Thermometer is an essential tool.

Comparing The 10 Best Compost Thermometers

1. REOTemp Compost Thermometer – Most Reliable Compost Thermometer

The REOTemp Compost Thermometer should be a product of choice for anyone looking for temperature monitoring reliability. It is the best way to take the guesswork out of your composting procedures.

From temperature readings and basic interpretation of the readings and temperature indications, you will be able to correctly time when to turn the pile, when to add more materials, when to add more water and when your compost is ready.

If you want to drip water directly to the plant roots, consider buying the soaker hoses.

However, if you are not familiar with this, don’t worry as the REOTemp Compost Thermometer package comes with composting instructions that come in handy. Perhaps the reason why this product was our best choice for reliability is due to REOTemp’s constant and continuous production of quality compost thermometers.

You will like the thermometer’s thick – 0.25” diameter stem that decreases the chances of bending when dipped. It is also thicker than any other compost thermometer present at its price range.

Besides, the hermetically sealed dial end won’t fog up easily thus making it possible to leave the thermometer in the heap overnight. Its reinforced construction also prevents the dial from easily separating with the stem and the products sturdiness benefits from the quality bimetal coils.

The other best feature of the REOTemp Compost Thermometer is how easy to read it is. It is demarcated in three temperature zones including the steady, active and hot zones. Each temperature zone indicates the current compost activity for easy reading and understanding.

2. Ecocycle Compost Thermometer – Most Simple & Clean Design

The Ecocycle Compost Thermometer wins the tag of a simple dial and clean designed compost thermometer. The thermometer might appear simple but has all the features of a high-quality product.

Some of the best features of the Ecocycle Compost Thermometer include:

• Long stem – you will enjoy the 20” long stainless steel stem featured in this thermometer. This is perfect for accurate readings and perhaps a great addition to any backyard compost thermometer. Temperature readings are done from the tip and takes randomly 30 seconds.
• Easy to read – the dial of this product is easy to read. Like our first product, it is color coded with various temperature zones. It also features 2 degrees temperature increments for enhanced accuracy.
• Anti-fog and waterproof lens – the only way of waterproofing and making the lens anti-fog is through the hermetically sealing the lens. This avoids fogging and moisture thus can be left in the compost even overnight.
• Long lasting – the Ecocycle Compost Thermometer offers features a thick – 6mm stem that ascertains long-term durability. With such a rigid stem, be sure it won’t break or bend.
• Free composting guide – like other manufacturers who care about their clients, Ecocycle provides a free composting e-book for clients purchasing this product. This helps beginners wade their way through the initial stages on how to create and maintain a compost pile.

3. REOTemp Heavy Duty Compost Thermometer – Heavy Duty Composting Thermometer

Yet another product from the REOTemp, the REOTemp Heavy Duty Compost Thermometer is an industrial grade compost thermometer. It is a perfect choice for those looking for a top-notch tool that handles heavy-duty compost tasks expertly.

The thermometer is available in various stem lengths, extending up to 36 inches. There are shorter stems for this model too. The diameter of the stem is 0.3” wide, perhaps thick enough to provide extra durability.

Like other models mentioned above, the REOTemp Heavy Duty Compost Thermometer is hermetically sealed to keep moisture out and prevent fogging. It is also important to note that it features dual temperature scales, allowing the users to read in both degrees Celsius and Fahrenheit based on preference.

Being an industrial setting compost thermometer, manufacturers provide a one-year warranty.

4. Cate’s Garden Compost Thermometer – Best Compost Thermometer for Accurate Readings

If you are in the market for the easiest and accurate way of making temperature readings from your compost pile, consider the Cate’s Garden Compost Thermometer. The thermometer comes with great features, perhaps the best being its accuracy level.

Among the intriguing features of this thermometer include:

• Utmost accuracy – the thermometer features 2-inch wide dial lens with color-coded temperature ranges. Color-coding and the small temperature increments make it easy for users to note even the slightest temperature changes.
• High-quality lens – the Cate’s Garden Compost Thermometer comes with high quality and lightweight PC coated lens that is hermetically sealed. This enables them to avoid fogging as well as moisture accumulation that may hinder visibility. The lens also has an IP55 water resistant rating.
• Rugged construction – for durability purposes, this compost thermometer features a tough and reinforced welded bolt that joins the dial and the stem. This ascertains long-lasting operations under any condition.
• Long stem – it features a 20-inch stem that is 0.2” wide. This provides for accurate readings, especially from the tip. It is a great choice for large backyard compost piles and takes approximately 30 seconds to make the readings.

5. Planteko Compost Thermometer – Best for any Gardener

The Planteko Compost Thermometer is a perfect way of alleviating worries of having your compost too dry or extra hot. This specifically designed compost thermometer always keeps an eye on the compost temperatures, providing insights as for when to do what.

Among the best features of this product include:

• Easy to read dial – it is of no need purchasing a thermometer that will make it hard to read out temperature changes. This is why the Planteko Compost Thermometer features an easy to read dial that can be read even with one glance.
• Extra thick stem – this product’s 20-inch thick stem is an assurance of a long-lasting product. The stem is also long enough to ensure that it gets accurate readings from any compost heap size without breakages.
• Premium quality lens – unlike conventional lenses used in basic thermometers that fog easily when left outside, the Planteko Compost Thermometer lens features a special coating that prevents moisture and fog.
• Free composting manual – you will benefit from the free guide on how to compost provided by the product manufacturers. This will help you achieve an effective compost.

6. Greenco Soil Gardening Compost Thermometer – Super Durability

The Greenco gardening thermometer for your compost is a highly durable device to give you long term diagnosis. The design features a robust 20-inch probe with a diameter of 0.2 inches.

The probe stem is has been ensured high durability because of the use of stainless steel. Furthermore, this compost thermometer provides decent visibility through the 2-inch broad dial.

For your ease, the temperature ranges are coded with distinct colors ranging from low to high temperatures. That’s how the probing thermometer gives you accurate temperature readings for your compost.

7. Thermometer World Compost Thermometer – Great For Beginners

If you have an immense passion for gardening, then you need to have an excellent compost thermometer for keeping your compost under check. With the compost thermometer by Thermometer World, you are promised a decent tool for keeping a check on the temperatures.

It is an ideal device for beginners that accurately measures the temperature of the compost pile. With its 11.7 inches stainless steel body, and a diameter of 50mm, you can be assured of using the device safely without damaging the probe.

Keep using it for a long term without the risk of corroding this tool. The manufacturer even offers customer service if you feel the device is not working correctly for you.

8. Mantis 201101 Compost Thermometer – Highly-Accurate

The Mantis 201101 is a decent compost thermometer with a straightforward design. Expect highly-accurate temperature readings of up to 240 degrees F with this model.

Furthermore, the 201101 packs a 20-inch long probe made of rugged stainless steel material for high durability. It also makes this device rust-proof with impressive longevity. The probe is sturdy to endure the force of compost pile without damaging the stem.

While it lacks color-coded temperature zones, yet it ensures high precision for your gardening tasks.

9. Tel-Tru GT300R Compost Gardening Thermometer – Most Stable

The GT300R promises highly stable temperature readings through its premium-quality 48-inch probe. The stainless steel stem maintains its durability with its 9.5mm diameter for you to precisely take readings of the compost pile.

This tool manages readings up to 200 degrees F and can withstand probing through dense soil or compost quickly. Tel-Tru has manufactured this unit for fulfilling your heavy-duty operations with ease.

10. Yardwe Soil And Compost Thermometer – Long-Lasting Usability

No products found.

For high-end usability and durability, the Yardwe compost thermometer has been fabricated using stainless steel and silver coating. That’s one reason why it will stay rust-proof for years.

Furthermore, this gardening equipment can be a great way of deducing the temperatures of not just compost piles, but topsoil as well. The dial has been sealed efficiently to keep it safe of fogging.

It’s fast, it’s accurate, and it gets the job done through its 20-inch probing stem. No doubt, the Yardwe compost temperature reader is an excellent unit for gardening operations, whether you are a beginner or an expert.

What are Some Common Compost Thermometer Issues?

• The probe is too Short: Your compost thermometer probe needs to reach the center of your compost pile in order to get proper measurements. Consider how much compost you typically have piled up so that you can get one with a probe that is long enough.
• Measurement Units: Some people prefer reading temperatures in Celsius and others prefer Farenheight. Compost thermometer manufacturers don’t always include both of these units together. A good compost thermometer will include both of these measurement units.
• Fogged Up Lenses: There is nothing more tragic than trying to read your compost thermometer only to encounter a fogged-up lens. A high-quality compost thermometer will also be completely anti-fog and waterproof.

How Hot Does Compost Get?

In the hottest conditions, hot compost can reach temperatures of 120-170 degrees Fahrenheit. However, it’s essential to monitor hot compost to ensure it doesn’t exceed 140-150 degrees. This heat is capable of killing microorganisms that are essential to the composting process.

Features of the Best Compost Thermometers

In order to ensure that you get the best compost thermometer for your needs, it’s important that you understand what features to look for. Believe it or not, a simple thermometer will not work. Here is what you need to look for if you want to get a high-quality compost thermometer.

Long Probe Stem and Sheath

In order to get the most accurate measurement, remember that the heat of your compost will be much different in the middle than on the top. For the most accurate results, you will need the probe stem to go all the way down to the middle of your compost pile. It will also ideally include a sheath to keep it in place. As a general rule of thumb, a good compost thermometer probe will be at least 20 inches long.

Dual-Scale Measurement Units

Most people have a particular measurement unit that they prefer. Whether you like reading temperatures in Celsius or Farenheight, you should have the ability to do both. A high-quality compost thermometer will come with dual-scale measurement so that everybody can read in the unit that they prefer the most.

Waterproof and Anti-Fog Lens

One of the best signs of a high-quality compost thermometer is having waterproof and anti-fog technology. This is relatively easy for manufacturers to do, and necessary for a moist compost environment. This way, you can also count on reading the thermometer for years to come.

A Reasonable Price & Nice Warranty

At the end of the day, a compost thermometer is just a standard thermometer with some extra features to help you with composting. Thermometers aren’t that expensive to produce or purchase. Keeping this in mind, you shouldn’t expect to pay that much for a good compost thermometer.

A manufacturer who is confident in the durability and quality of their product might include a nice warranty. Some of the best compost thermometers will even include a lifetime warranty.

Clear Instructions and Guidelines

If this is your first time using a compost thermometer, you will definitely need a little bit of assistance. Although it is easy to learn how to use a compost thermometer, it’s important to have a concise user guide with instructions that are relevant to a particular thermometer you chose.

Some of the best compost thermometers come includes with specific instructions on both how to use the thermometer and how to properly compost. If you are new to composting or using a compost thermometer, this will come in handy.

Things to Consider Before Buying a Compost Thermometer

Compost thermometers can be the hardest gardening tools to search for. This is perhaps due to the limited knowledge of how to use them, and the features characterizing the best product.

That said, what should you really consider when searching for a compost thermometer? Here are the four main features to look for.

Measuring Units

The standard temperature readings vary from different regions or continents. Whereas other counties use degrees Celsius as their standard, others prefer their readings in Fahrenheit.

A good example is that those living in America will like their readings in Fahrenheit while those in the UK will want a thermometer measuring in degrees Celsius. Different thermometers provide varying readings. However, it is prudent to consider a dual scale thermometer, offering readings in both measurements.

If you are using a compost thermometer, you should also consider buying a reliable grain moisture tester as it helps to measures the moisture content of the grain. A good grain moisture tester helps you access the quality of grains quickly and precisely.

Probe Length

Compost temperatures are usually taken from the center of the compost heap/pile. Therefore, you would want a thermometer that reaches the center of the heap, without breakage or kinking.

Therefore, consider a thermometer with a long and thick probe. This will ascertain that you make accurate measurements, whilst ensuring that the stem doesn’t break easily when being used.

Construction

Compost piles never lack moisture. Besides, you could be leaving your thermometer in the compost pile for quite a long period. Therefore, it is of immense importance that you get a rust-resistant thermometer. It should also be sealed tightly to prevent water leaking to the dial.

Temperature Range

Nearly all high-end compost thermometers come with three classifications of temperature range, i.e., the steady, active, and hot zones. This makes it easier to monitor the temperature levels of your compost heap. Additionally, small temperature increments, of up to 2 degrees Celsius make it easy to detect even the slightest changes in temperature.

When and How Often Should You Turn?

Many gardeners prefer turning the heap after each burst of heat. Others prefer turning based on the number of days. However, this isn’t a scientific approach to making a good quality compost heap.

So to say, compost should be turned when the temperatures reach between 140 degrees to 150 degrees. It should be left until it achieves this temperature again, probably after 5 to 7 days.

What Makes the Pile Heat Up?

Perhaps this is the most interesting question of the day. The contents of your compost heap heat up due to the actions of Microbes. The heat generated through the microbe’s metabolic activities such as eating, excreting, and multiplying is responsible for such heat.

Bacteria is the common microbe responsible for this, but fungi and large soil organisms can also be found. The increasing intensity of microbe activity is the reason behind increasing temperature levels with different stages.

Ready To Buy The Best Compost Thermometer?

To ensure that your compost pile matures effectively, you must consider using a compost thermometer. However, not any thermometer can ascertain this, but the best can.

As mentioned, readings obtained from this instrument guides on the various changes and additions made to the heap.

Among the changes includes when to turn, when to open up, when to add water and when the heap is ready. Note that proper monitoring of this is a receipt for a high-quality compost heap result.

As mentioned the best thermometer ought to be made from the strongest material, have appropriate probe length and favorable measuring units. This will make it easy to read and monitor temperature changes in your heap.

Did you liked our review on “The Best Compost Thermometers”? Then, you’ll love this great review on “Top rated Compost Aerators” as well.  If you have a beautiful garden to tend to, what you need is the best hand-held spreader.