Do I mulch old tomato plants into my Raised Bed Garden or remove the dead plants? - Ask Extension
Hi Garden Professionals,
I have a small Raised Garden Bed in Towson. 1. Should I mulch my old tomato plants into the soil, or remove the dead toma...
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Do I mulch old tomato plants into my Raised Bed Garden or remove the dead plants? #919166
Asked October 03, 2025, 12:18 PM EDT
Hi Garden Professionals,
I have a small Raised Garden Bed in Towson. 1. Should I mulch my old tomato plants into the soil, or remove the dead tomato plants totally?
2. Next should I add new Leaf Gro on top for winter, or wait until spring?
3. How should I prepare my garden now, for spring for best results? Cover with black plastic, to keep soil warm all winter and kill unseen weeds? Help!
I appreciate your expertise,
Bonnie
Baltimore City County Maryland
Expert Response
Hello and thank you for your question!
Tomato plants often end the season with one, if not multiple, diseases. Whether fungal or bacterial, it is best to remove them (and any fallen plant material) from the beds to prevent early infection next season. You do not have to dig out the roots, simply snip at, or above, the soil line and dispose of the stem and leaves. The roots will die over the winter and provide biomaterial as they decompose.
As for the leaf-gro compost, I would add it whenever is the most convenient for you. Generally, fresher compost (less aged) is best for fall application as it has all winter to further break down and integrate into the soil, as well as act like a mulch to prevent nutrient leaching through the winter. Finished compost (fully aged or commercially made), on the other hand, is best for spring application to give the plants an instant boost during the beginning of growth, when they need nutrients the most, and to aid in moisture retention. All that being said, leaf-gro does not have a significant amount of NPK so you would want to add a fertilizer in the spring anyway. Applying in the fall, if that time suits you best, would not lose any of the benefits of the compost, so I would err on the side of personal convenience.
To answer your final question, beds are healthiest when they are full/covered. Whether that is by cold crops (collards, kale, mustards, beets, turnips, garlic, etc.), cover crops (crops planted to be killed off by winter’s freezes and add biomaterial or mowed down and tilled in at spring for the same reason), or mulch. Plastic is only recommended for solarizing an area where weed seeds, or plants that are difficult to kill, exist. Plastic over soil for extended time can have a detrimental effect on microorganisms, beneficial soil dwelling insects and fungi that are important to both soil tilth and nutrient uptake by plants, as well as incorporate possible microplastics or chemical leaching into the soil. Organically derived mulches, such as pine needles, hardwood mulch, leaf litter, straw or seedless grass clippings are all better choices that will serve the same purpose. And yes, covering beds that will be empty during the winter is a better option than leaving them bare.
Please feel free to ask follow up questions if you have any!
Tomato plants often end the season with one, if not multiple, diseases. Whether fungal or bacterial, it is best to remove them (and any fallen plant material) from the beds to prevent early infection next season. You do not have to dig out the roots, simply snip at, or above, the soil line and dispose of the stem and leaves. The roots will die over the winter and provide biomaterial as they decompose.
As for the leaf-gro compost, I would add it whenever is the most convenient for you. Generally, fresher compost (less aged) is best for fall application as it has all winter to further break down and integrate into the soil, as well as act like a mulch to prevent nutrient leaching through the winter. Finished compost (fully aged or commercially made), on the other hand, is best for spring application to give the plants an instant boost during the beginning of growth, when they need nutrients the most, and to aid in moisture retention. All that being said, leaf-gro does not have a significant amount of NPK so you would want to add a fertilizer in the spring anyway. Applying in the fall, if that time suits you best, would not lose any of the benefits of the compost, so I would err on the side of personal convenience.
To answer your final question, beds are healthiest when they are full/covered. Whether that is by cold crops (collards, kale, mustards, beets, turnips, garlic, etc.), cover crops (crops planted to be killed off by winter’s freezes and add biomaterial or mowed down and tilled in at spring for the same reason), or mulch. Plastic is only recommended for solarizing an area where weed seeds, or plants that are difficult to kill, exist. Plastic over soil for extended time can have a detrimental effect on microorganisms, beneficial soil dwelling insects and fungi that are important to both soil tilth and nutrient uptake by plants, as well as incorporate possible microplastics or chemical leaching into the soil. Organically derived mulches, such as pine needles, hardwood mulch, leaf litter, straw or seedless grass clippings are all better choices that will serve the same purpose. And yes, covering beds that will be empty during the winter is a better option than leaving them bare.
Please feel free to ask follow up questions if you have any!
Dear Extension Foundation,
Wow, Wow, Wow ….thank you so much for sharing your extensive expertise, which I really needed right NOW!
Very timely! I’m following your instructions ….immediately!
You have really made a difference. Thank you so much. I did not know any of this info. , but NOW I do, thanks to YOU!
Foodie,
Bonnie
On Oct 3, 2025, at 8:31 PM, Extension Foundation wrote:
You are so welcome! Give us a shout anytime you have a question. Happy gardening!!
