Compost Tomato Plants – How and When You Should Do It?

Recycling is undoubtedly the future in the modern conservation of resources, and nowhere is this more valuable and true than the act of composting. This ‘soil conditioner’ is particularly useful with the incorporation of tomato plants.

Composting excels at reducing greenhouse gas emissions, limiting the amount of organic waste that is deposited into landfills, and helps procure a flawless looking garden that cuts down on your fertilizer costs.

The different variables that come into play with tomato plants and roots are the levels of nitrogen involved as well as the pH of the overall heap. The how and when to compost tomato plants relies entirely upon preparation, execution, and time of year to act. So where do you get started?

When You Should NOT Compost Your Tomato Plants?

So you’ve harvest your tomatoes and you want to compost the plants. For a beginner gardener, composting your tomato plants seems very natural and safe. However, that’s not entirely the case.

If your plants are infected by a disease or viral infection (such as the mosaic virus) composting them would be the worst idea. The virus might spread and affect future crops all over your garden. That’s is really not what you want.

Before you proceed to compost your plants, make sure they are healthy looking and there’s no sign of any viral infection or disease. If you find tomato plants that are indeed infected you need to carefully wrap them up with a garbage bag, tie it up and throw them out. But do not compost them!

Those are the safety precautions we had to cover. Now, let’s proceed to the steps you should take to compost healthy tomato plants.

The Tools You Need

Having the proper tools in your arsenal for effective composting is critical, and made even more so if you are performing nuanced versions of the process such as utilizing tomato plants.

It is a fruitless (no pun intended) endeavor to begin the task at hand unless you are fully capable of completing all the steps with ideal devices to fit each need. So what are must have utensils to put to use and why?

If you are of the ilk that does not prefer to use large amounts of your property for this operation, a compost bin should be at the top of your list to acquire. The purpose of this receptacle is to have a controlled environment for the decomposition of tomato plant waste to transpire.

compost bin
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Although some people prefer to just have a heap instead, the benefit of a bin is that it is much easier to contain and shield it from outside forces, be it weather or otherwise.

No compost operation is worthwhile without a solid rake. Equal distribution of tomato plant matter over a pile of waste is the lifeblood of composting. It is even more beneficial to employ a shovel to allow for peak aeration.

Because plants come in all shapes and sizes, a garden fork is also recommended to break down awkward ‘suckers,’ which is the term for tomato branches.

garden fork

Temperature gauges are a no-brainer for accurate readings to any green thumb connoisseur to begin with, but they are twice as important when using tomato plants since this type of vegetation can harbor many pests and diseases.

A thermometer is worth its weight in gold to oversee the destruction of harmful pathogens while at the same time being able to monitor if your compost heap is getting too hot.


Excessive heat can bring the process of waste decomposition to a halt, undoing all your efforts in one fell swoop. Adding a pH and moisture meter into the fold will ensure everything is developing according to plan.

Finally, a sieve will break down large chunks of matter making swift distribution of the compost achievable. This tool is invaluable to those who plan to make potting mixes with their tomato plants.

How To Compost Tomato Plants?

Though the procedure with tomato plants is similar to traditional types of composting, there are a few things to keep in mind. This family of roots are known as ‘green’ because they have high levels of nitrogen. This element increases heat in piles, so it must be counteracted with carbon that can be readily found in leaves and other ‘brown’ components.

The first step in your journey is to gather your tomato plant waste and set it into the designated bin. The optimal spot for this is near your garden or kitchen so you are able to discard matter with ease. If you do not have a container, choose an area for a heap on your property that is shaded so the elements have minimal impact on the maturation process.

compost container

Commence with the literal breakdown of the tomato plant, removing stems and foliage. The same can be done with branches and leaves or carbon-rich items like straw. Your shovel and garden fork will make handy weapons during this step to chop them up with minimal effort.

Organize your bin interweaving the tomato waste and ‘brown’ scraps by alternating them one on top of the other. This will have the nitrogen and carbon working in unison to prioritize not making the decomposition process too hot. Piles should be layered with brown components on bottom and top, with chopped up tomato plant matter residing in the middle if possible.

Next, aeration is key if you are to generate any level of success with a compost heap. Oxygen is the second most important aspect of decomposition besides the material that is decaying. Your rake or garden fork should be used to flip the material on a consistent basis. A good rule of thumb is to undertake this twice a week or more, depending on the size of your bin or pile.

After aeration it is a good time to check the amount of water in the heap by using a moisture meter. The sweet spot is between 45 to 60 percent, with the latter being more acceptable in larger piles. If there is too much moisture, aerate again until you are satisfied with the reading.

garden rake

The elements in your compost interact almost immediately to alter heat levels. Check the temperature with a thermometer to be certain that the range falls between 125 degrees and 165 degrees. Colder heaps should be flipped with a shovel until desired levels are obtained. Pests enjoy feasting on tomato plants without regulated temperatures, so it is vital this step is not skipped.

Compost heaps should have a neutral PH of 7 to magnify its effectiveness. Because tomato plants are acidic, they may drag down this number to unsatisfactory levels. The addition of lime into a bin will balance out this action effortlessly.

It takes about 5 months for ‘green’ waste to decompose entirely. This is when it is at its most useful since the amount of nutrients are at their peak. Your sieve has the ability to diversify the matter into more even batches if necessary. What’s leftover is a perfectly blended concoction of compost that is superb at filtering soil and improving its health to grow other plants and crops dramatically.

Composting Tomato Plants: What Time Is Ideal?

Fertilizing tomato plants during the winter months may seem counter-intuitive since little vegetation thrives in cold weather, but in actuality this time period allows positive nutrients to fully flourish. Composting overall is a marathon rather than a sprint, and for good reason.

Dropping temperatures ensure that the process of decomposing waste slows to a controlled, steady pace. The reason this is ideal is because the microorganisms beneficial to healthy, sustainable soil mature more efficiently in chillier conditions.

An easier way to discern why weather plays such a vital role in a pile’s success is to understand that blazing hot temperatures kill the very nutrients gardeners wish to utilize in dirt. While heat certainly has its place in the ‘life’ of a heap from beginning to end, it is not a factor that can be left unchecked.

The fact that there is less sunlight during fall days is an added bonus to procure powerful organic matter breakdowns among the sections of waste.

snow on cherry tomatoes

There is obviously enthusiastic composting that takes place before summer by many individuals, but it should be understood that these piles are more volatile and require additional attention to manage.

This is because their temperature ranges change frequently, necessitating increased human intervention. For those who are ardently against tomato plant composting during cold spells, it would behoove them to realize that no two piles of vegetation are created equal.

This is to say that undertaking this process during the spring as opposed to fall will produce vastly different outcomes. Warmer climates for tomato plant decay will all but guarantee fewer integral microorganisms will be retained, thus making the compost less rich in nutrients.

Conversely, when degrees begin to drop outdoors, waste starts to take on a life of its own to the benefit of those who set the process of science in motion. More minerals that find their way into the dirt itself extends the longevity of its effectiveness as a fertilizer.

Bottom Line

Even though there is an art to composting, it is a skill anyone can learn and put into action with organization and a bit of preparation. Tomato plant waste behaves slightly different than other categories of vegetation, but don’t let its potential unpredictability intimidate you. Every scrap, leaf, branch or waste placed into a bin serves its purpose in generating safe and dynamic nutrients to create quality compost.

Tomato plants are no different, and are terrific sources of folate, potassium, and vitamin K, all of which aid in the progress of ‘cleaning’ dirt. Fertilizing with this type of vegetation is prudent for beginners who prefer a more gradual pace to learn the craft since it can be done at a time of year when there are less outside factors to take into consideration.

The how and when to compost tomato plants ultimately boils down to your strategy and dedication to follow each step in earnest. If performed consistently, the output can save your crops, the bottom line on your gardening bill, and even the planet from dangerous gasses.

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Emily Jones
My name is Emily Jones and I'm a vivid gardener and tomato lover for over 30 years. I've gained a lot of knowledge and tips related to growing and caring for tomatoes. Now I'm dedicated to help beginner tomato lovers grow their own tomato plants.