The soil might have actually been too rich for carrots. In my experience with too much nitrogen grow great tops but the root doesn't form properly.

It's the urine. Try sun bleaching it by spreading out the piles to get rid of the ammonia.

It's a hot manure. Break the rules, gardening gets a lot wrong or is to finicky but for a starting idea -

"Hot manures are high in nitrogen compounds, which decompose quickly in the compost pile and generate a lot of heat in the process. In fact, traditional hothouses harnessed the energy of rotting manure to grow seedlings and cuttings during winter. Hot manures include chicken, duck, and horse.

Cold manures are low in nutrients and release less heat as they break down, posing less risk of burning your plants. Examples are cow, goat, and sheep – ruminant animals that regurgitate and chew cud, extracting most of the nitrogen from their plant-based diet before it comes out the other end. Llama and alpaca aren’t ruminants, but their manure is low enough in nutrients to be considered cold."

No worries at all, I appreciate the curiosity! You’re spot on—electronic monitoring becomes most valuable at larger scales, which is why our upcoming Monty Pro line is tailored for industrial composting facilities and large-scale operations. These setups can really benefit from the efficiency and cost savings that our data-driven insights offer, like optimising aeration cycles or catching inefficiencies before they become costly issues. You can check out the product website here: (https://www.monty-pro.com)

For households, the focus is less on cost savings and more on providing convenient insights to help everyday composters get the most out of their efforts. It’s all about enriching the overall composting experience on a smaller scale :)

Looking at the Hardware requirements of the project:

``` Hardware Requirements

    Raspberry Pi (Zero 2 or another model with BLE support).
    Monty Home BLE Device.
    Additional hardware specific to each project, such as an LED, OLED display, and IFTTT account.

You're looking at ~$100 worth of equipment. A very low entry price point

For Monty’s system, we use sensors from Bosch and Sensirion. During our initial prototyping phase, we tested around 20 different types of sensors and found they had the most workable results across a range of composting environments.

Feel free to share more about your project ideas— happy to dive deeper if it helps!

Oh wow, thanks for sharing! We’ll definitely drop a post in there :)

You’re absolutely right— a temperature gauge is a fantastic tool for monitoring for many composters who are focused on the basics of maintaining an active hot composting pile.

Where our system shines is when you want to go a little deeper. For example, adding data on gas, moisture levels, and air pressure allows users to troubleshoot or optimise their process more effectively. Is the activity aerobic or anaerobic? Is your moisture level tipping the pile too far one way or another? These kinds of insights can help when composting setups or inputs get more complex, or when things stall and you’re not sure why.

That said, we totally get that not everyone needs all the bells and whistles—sometimes a reliable temp gauge and your composting instincts are all you need to make amazing, healthy compost!

I can barely get my compost more than 5C above ambient. But I think it is mainly because the compost bin isn't big enough (one of those black plastic daleks), so has too much surface area/volume. Also, it is in a very shady spot.

How do you verify the expected metabolic processes are occurring that produce said temperatures?

We use sensors from Bosch and Sensirion in our systems. They’re reliable and durable, even in tough environments like compost piles, where heat, moisture, and microbial activity can put tech to the test. Finding the right sensors took a lot of trial and error for us, especially since composting conditions are so unforgiving.

Let us know if you decide to pick up the project— we’d love to cheer you on or compare notes!

i did a hobby project like this for soil moisture. here's a messy repo that i made when i could barely code. it points to some capacitive sensor guides. https://github.com/smcalilly/sensor

To dive into the utility of the sensor readings-- The main gas we monitor is Total Volatile Organic Compounds (TVOCs), which act as a general proxy for decomposition activity. Combined with temperature data, this gives a strong indication of whether the activity is aerobic (a healthy compost pile) or anaerobic (not ideal and potentially smelly!). For example, a spike in TVOCs with decreasing oxygen availability often flags anaerobic conditions.

In terms of air pressure, this is used as part of our pile turn events detection in our companion app Monty Mobile. The app also analyses other data to assess how changes in conditions (e.g., moisture levels, turning frequency) affect decomposition. For most users, though, the general proxy is plenty— by identifying when a pile is “active” or “stalled,” they can tweak their process (e.g., adding browns, adjusting moisture, or aerating).

Compost is incredibly diverse, and the results will vary depending on the setup (tumblers, bins, worm farms) and inputs (manure, food scraps, garden waste). That said, 24/7 data from our system helps streamline the behaviour-change process. Rather than relying on a “try-wait-try-again” approach, users get immediate feedback, which can be a game-changer for both beginners and seasoned composters.

As for me, Monty has been a massive learning tool. Using the Monty Mobile app has personally helped me engage more with my compost pile and remember to add feedstock to adjust the pile when needed. It definitely makes me feel more in tune with what’s going on!

I hope this clarifies things! Happy to chat more :)

https://en.wikipedia.org/wiki/Home_Assistant for those like me who have never heard of this software

Not yet, but maybe you? :)

Thanks so much for sharing these resources—this is fantastic!

If you’re into LoRaWAN, you might be interested to hear that we’re also developing an industrial composting monitor that incorporates LoRaWAN tech. Here’s the promo video link if you’d like to check it out: https://www.youtube.com/watch?v=TZFiiwLhZh8&feature=youtu.be

/? crop monitoring wikipedia: https://www.google.com/search?q=crop+monitoring+wikipedia ...

Precision agriculture: https://en.wikipedia.org/wiki/Precision_agriculture

Digital agriculture: https://en.wikipedia.org/wiki/Digital_agriculture

/? crop monitoring system site:github.com https://www.google.com/search?q=crop+monitoring+system+site%...

SIEM: https://en.wikipedia.org/wiki/Security_information_and_event...

I need to monitor my compost to keep it from freezing in the winter. Probably not what OP's system is for, given that they are from Australia.

The biological processes produce enough heat to keep the thermally insulated compost bin from freezing easily down to -15C (~5 F). But this requires that there isn't too much finished compost in the bin that won't produce heat any more, so any turn downwards on the thermometer means I'm probably late in emptying the bin. Which happens every year when it gets cold (below -20C/-5F), but can be remedied by a 40W light bulb for 48 hours to heat up and restart the composting.

Another thing that needs to be monitored is humidity, because too humid and the compost goes anaerobic and starts rotting instead of composting. This I "monitor" by smell but this project has some kind of gas composition sensor which could be useful. I don't have issues with this any more as I have practically unlimited supply of wood chips to keep it dry.

But the wood chips bring another problem which is pH levels that may go too low. Here's where I'd really like to have a monitor so I could estimate if I need to do something to adjust the pH.

I don't.

My most-productive compost operation mostly just consisted of just piling stuff up beside my brick shed, which was conveniently near an outside door on my kitchen.

The rest of the process consisted of giving it a bit of a toss with a hoe, a shovel, or a fork if I was outside, bored, and felt like doing that, or giving it a bit of water from the garden hose if it had been very hot and dry. And I did as little of this as possible because taking care of compost, while certainly interesting to me, is just not something I generally enjoy doing.

I really didn't pay much attention to it.

By the time spring came 'round again and I had a use for the stuff, I had plenty of it for the garden.

And this worked very well -- for me, on my scale, in my region, with my needs.

Therefore, I do not need to monitor my compost.

---

But not all composting operations are lazy. Sometimes, they are very active. And some operations are large enough (or the available space small enough) that real estate becomes a seriously-limiting factor.

And in these instances, optimizing the process to get higher-quality compost faster can become a very desirable goal.

Optimization of composting is not dissimilar to optimization of any other process, wherein: Having some good data is better than having no data.

I agree with everything else that has been said in this thread!

Just to add on, proper composting helps retain more nutrients in the final product, which is great for soil health, and it also reduces harmful emissions like methane that occur when the process turns anaerobic.

To ensure the pile is actually composting effectively.

To monitor the compost