Even the most experienced gardeners sometimes have trouble knowing what to do with spent tomato plants. Do you compost them? Burn them? Throw them away?
Composting is beneficial and a valuable skill for anyone interested in helping the planet or becoming self-sufficient in rich soil and compost for their garden. Bringing in compost from outside sources can be expensive and physically taxing, after all.
But what if you don’t have a compost pile? How else can you get rid of plants after the garden season is over? Keep reading to find out more about what to do with your spent tomato plants.
The risks of composting tomato plants
Composting tomato plants comes with several risks, mainly that you risk spreading diseases through your soil next season if you compost diseased tomato plants.
Let’s discuss the risks more in-depth before getting into the four ways I’d recommend disposing of your tomato plants at the end of the gardening season.
When adding tomato plants to your compost pile, taking the necessary precautions to avoid spreading disease is important. Compost piles can provide a warm, moist environment where many plant pathogens thrive, and diseased tomato plants can introduce these pathogens into the mix.
Common diseases like early blight, late blight, fusarium wilt, and bacterial canker can spread through compost to infect other tomato plants as well as potatoes and peppers. And once a disease takes hold in your compost pile, it can linger for years.
According to UMass Extension, “Plants with especially damaging diseases, such as late blight of tomato and potato, which is caused by the fungus Phytophthora, should not be composted because if the disease is not killed in the composting process, the resulting spread of the disease can be devastating.”
To prevent spreading disease through compost, always thoroughly clean tools before using them on healthy plants, and never add diseased plants or plant material to the compost pile.
Volunteer plants in springtime
Another risk to consider when composting tomato plants is that you may end up with volunteer tomato plants in the springtime. This isn’t a particularly hazardous risk, but it’s worth mentioning.
Tomato seeds can survive the composting process and germinate in spring, leading to unwanted tomato plants in your garden. If you don’t want tomato volunteers, make sure to remove all the fruit from your plants before composting them. You can also let the fruit rot on the plant, which will kill the seeds.
If you don’t mind a few volunteer tomato plants, composting is a fine way to dispose of your spent tomato plants. Just be sure to avoid composting any foliage or stems with signs of disease.
What to do with spent tomato plants
Now that we’ve gone over the risks let’s get into the four ways I recommend disposing of your tomato plants at the end of the gardening season
1) How to compost tomato plants
You might not want to compost your old tomato plants because tomatoes are notorious for spreading disease through compost. If your compost pile is well-maintained and regularly reaches temperatures of 130-150 F, you don’t have too much to worry about.
That being said, most beginner composters aren’t building compost piles with the amount of material and aeration needed to achieve what’s called a hot compost pile. Those new to composting will often pile up their yard and food scraps without turning the pile or chopping up their scraps into pieces small enough to break down quickly and heat up the pile.
And if this is you – that’s OK! You have lots of time to work on your composting skills and refine your composting process so that it’s more efficient in the future. For now, take a look at how to build a compost pile and keep practising your composting skills. If you’re having issues with your compost pile (too slimy, not heating up, etc.) this article will help you sort it out.
For the more experienced composted who do have piles that get hot, compost away! Regular old tomato blight isn’t much of a match for a hot compost pile that maintains its heat for a few weeks at a time. If you have any doubt about how hot your compost pile gets, buy a long metal thermometer to check.
2) Sending your garden plants to a municipal composting facility
Many people turn to municipal composting facilities when it comes to disposing of diseased plants in the garden. But how exactly do you go about sending your plants off to be composted?
First, check with your local waste management services to see if there is a facility in your area that accepts these kinds of materials. Some cities might have designated drop-off locations for yard waste, including diseased plants. Or, you could inquire about curbside pick-up for compostable materials.
Keep in mind that commercial composting facilities often have higher temperatures in their compost piles, which can effectively break down diseases and prevent contamination. Plants with signs of disease are sometimes accepted at commercial composting facilities because they can be disposed of here without contaminating the compost being produced.
If you do choose to compost some of your diseased plants this way, make sure to thoroughly clean any tools or equipment that may have come into contact with the diseased plants before using them on healthy ones. Either way, sending diseased plants off to be composted can help contribute to a healthier garden and environment.
3) Burning spent tomato plants
In some cases, the best way to dispose of diseased plants is simply burning them. This is often the case with tomato plants that are heavily infected with Phytophthora root rot, as there is no treatment for this disease, and it can quickly spread to other nearby plants.
Burning diseased tomato plants can help stop the spread of the disease and prevent it from infecting other plants in your garden. However, you should only burn diseased plants if there is no other way to dispose of them. Be sure to check to see if burning is an option in your area before lighting a fire, and read up on fire safety tips before attempting to burn plant remains.
4) Trench composting tomato plants
Trench composting is a method of composting that involves digging a trench in your garden and burying spent plants and other organic matter in it. This is a good way to dispose of diseased plants since it effectively isolates them from the rest of your garden.
To trench compost, dig a trench that is about a foot deep and wide enough to fit all of your plant material. Chop up your tomato plants and other plant material to help them break down faster. You can then bury your plants in the trench and cover them with a layer of soil. Water the trench well so that the plant material decomposes quickly.
After a few months to a year, the plant material will have decomposed, and you can then use the trench as a planting bed for new plants. This is a great way to effectively recycle nutrients back into your garden.
FAQ on how to get rid of old tomato plants
What do I do with spent tomato plants?
There are a few different options for disposing of spent tomato plants. You can compost them, send them off to a municipal composting facility, burn them, or trench compost them.
Can I compost diseased tomato plants?
In some cases, you can compost diseased tomato plants. However, you should only do this if the diseased plants will go to a commercial composting facility with high temperatures in their compost piles. This can help kill off any diseases and prevent contamination. Experienced composters might also be able to effectively compost tomato plants with blight, given their compost piles reach a high enough temperature.
Can I burn diseased tomato plants?
Yes, in some cases, you can burn diseased tomato plants. This is often the case with tomato plants that are heavily infected with Phytophthora root rot or bacterial canker, as there is no treatment for this disease, and it can quickly spread to other nearby plants.
What do you do with compost after tomato blight?
If you have composted tomato plants with blight, it is important to understand that the compost may still contain the disease. Because of this, it is important to use the compost in a way that will not contaminate other plants. One option is to use it as mulch around trees or shrubs. Another option is to mix it with other soils in a garden bed that will not have any susceptible plants growing in it.
What plants should not be composted?
In general, you should not compost any plants that are diseased or infested with pests. You also shouldn’t compost any invasive plants, as they could spread their seeds in the compost and cause problems. Finally, you shouldn’t compost any plants or grass clippings that have been treated with chemicals, as these could be harmful to your plants.
Should you remove old tomato plants?
Yes, you should remove old tomato plants from your garden at the end of the growing season. This will help prevent diseases and pests from overwintering in your garden and infecting your new plants. It will also give you a chance to add some fresh organic matter to your compost pile.
How do I save my tomato plants for next year?
If you want to save your tomato plants for next year, you can take cuttings from the plants and root them in potting soil. You can also dig up the plants and pot them indoors over the winter. You can also save seeds from your tomato plants to grow next year.
Can I eat the tomatoes from a plant that has blight?
Tomato blight doesn’t transfer to humans, so tomatoes from affected plants are generally safe to eat. Cut off the most affection portions of the fruits if you plan to eat tomatoes that have been affected by blight. Of course, not everyone wants to eat blighted tomatoes, so there is no harm in disposing of them.
Does tomato blight remain in the soil?
Yes, tomato blight can remain in the soil for up to four years. This is one of the reasons why crop rotation is common among farmers who grow tomatoes.
Can you reuse potting soil for tomatoes?
Yes, you can reuse potting soil for tomatoes. However, you’ll likely need to reinvigorate the soil by adding some organic matter to it. Compost, worm castings, bone meal, and kelp meal are all options. Crop rotation is commonly practised when growing tomatoes to avoid disease, so consider planting something different in that soil next time you use it.
You can dispose of your spent tomato plants in a few different ways. You can compost them, send them off to a municipal composting facility, burn them, or trench compost them. Each method has its own set of pros and cons, so be sure to choose the one that is best for you and your garden.