As a fellow gardener, I love using mulch in my garden. Mulching comes with unique benefits and is the ultimate multi-purpose tool in gardening. However, it can be a nuisance when I notice unwanted tree seedlings springing up nowhere.
I know I’m not the only one out there with this issue. If you’ve found your mulch has tree seedlings and you’re unsure how to deal with them, keep reading! In this article, we’ll be discussing what mulch is, why seedlings sometimes grow out of mulch, and steps on how to get rid of tree seedlings in mulch.
What is Mulch?
Mulch is any material spread on the soil’s surface to modify the plant’s environment. Mulch comes in many different types of material, both synthetic and organic. Common examples of mulch include pine needles, straw, leaves, or even tree bark.
Why would a gardener use mulch in their garden? Mulching has a multitude of benefits, including:
- Regulating soil temperatures. A layer of mulch can help lock in soil temperature and keep the soil consistently warm or cool. This is particularly helpful for those living in environments with unstable weather conditions. For example, a gardener living in a warmer climate might mulch around their cabbage plants to keep the soil comfortably cool in case of a random heatwave.
- Maintaining soil moisture. Laying down mulch around the base of your plants slows down the rate of evaporation, leading to soil staying moist for more extended periods.
- Pest deterrent. Some types of mulch (such as bark made from cedar and cypress trees) contain a natural oil that deters pests. However, not every type of mulch is used for pest deterrent; most organic mulches will not aid in pest prevention.
- Weed suppression. Adding mulch to your garden can effectively stifle weeds, leading to healthier plants overall.
While mulching can overall reduce the appearance of unwanted weeds in your garden, you might find an occasional tree seedling sprouting up from the mulch. Let’s read further to understand why tree seedlings can grow out of mulch and how to get rid of these nuisances.
Why is There Tree Seedlings in My Mulch?
Tree seedlings seem to pop out of nowhere sometimes. Tree seeds drop from a mature tree and result in multiple saplings scattered everywhere. Seedlings can also sprout up from an enormous tree (these seedlings are called “suckers”).
Seedlings in mulch can be caused by the presence of a nearby tree depositing seeds into the mulch, which subsequently results in seedlings growing. In addition, mulch containing organic material can have many nutrients, resulting in the tree seeds developing into seedlings.
Another way seedlings can form in mulch is dependent on the material of mulch being used. Organic mulch is often sourced from materials that come from trees, leaves, branches, bark, etc. Accidents happen in gardening, and if tree seeds are not carefully removed from the mulch material, they could quickly sprout saplings in the mulch. Seedlings can sprout up once the mulch has been layered onto soil and treated with water, sun, and fertilizer.
Luckily, tree seedlings in mulch can swiftly be taken care of with the right tools. Read on for steps on how to remove tree seedlings from your mulch.
Methods to Remove Tree Seedlings
The key to easy removal of tree seedlings is timing; the earlier you detect them, the easier it will be to remove them from your mulch.
The first (and simplest) method is to pluck out any tree seedlings you might find hanging out in your mulch. Be cautious about pulling seedlings. However, you want to make sure you pull out the entire root system of the seedling. Any roots left behind can regenerate and develop into yet another seedling, and you wouldn’t want a whole cycle of seedlings!
You can also stifle the seedlings by layering on extra mulch or a plastic tarp. It might seem weird to fix your mulch problem by adding more mulch, but the key to what we’re trying to do is stifle the seedlings and deprive them of the strong sunlight they need to grow. Layering on extra mulch/plastic blocks out the sunlight and can kill the plant by blocking one of the most necessary facets of plant growth.
Surprisingly, salt can also be an effective tool against tree seedlings; and is a natural alternative to herbicides that could potentially harm more than just seedlings. First, cut down the seedling to the ground and drill a hole in the center of the sapling. Next, pour in some rock salt, followed by just a tiny amount of water. This should effectively exterminate the seedlings without using harsh herbicides and chemicals.
If you find that the seedlings are too much to handle, you can also resort to a chemical fix for your seedling infestation. Of course, not every gardener feels comfortable using chemicals, but the option is there.
Triclopyr is a herbicide that only affects broadleaf plants, so you don’t have to exercise as much caution as you would with other herbicides. The downside to this is if you have mystery seedlings growing out of your mulch, this might not be very effective or helpful. However, glyphosate is a step up if you don’t have luck with triclopyr.
Glyphosate is another type of herbicide you can use to kill off seedlings, though be warned: glyphosate is nonselective, meaning it will kill anything it touches. Therefore, if you opt to use glyphosate, I strongly urge you to handle it carefully
On the whole, I don’t recommend using herbicides to remove tree seedlings from your mulch. It’s straightforward to misuse herbicides, which could devastate your whole garden if things go even slightly haywire. Instead, removing tree seedlings by hand is a chemical-free and effective way to rid your mulch of tree seedlings.
Tips on Using Mulch
You can buy mulch at any garden center or hardware store, but it’s much more cost-effective to make your mulch! As we’ve already learned, mulch can be made from simple materials you have lying around your yard. So next time you are outside raking leaves or collecting fallen branches, save the scraps to use as mulch for your garden. Tip: if you try to mulch your grass clippings, please make sure your grass is pesticide-free.
If you are home-making your mulch, please make sure the materials are dried out first. Using wet mulch can suppress oxygen levels from reaching the soil, harming your plant’s health.
As a general rule of thumb, you should apply a 3-inch layer of mulch to your garden. Sometimes, certain plants require a thinner or thicker layer of mulch, so I recommend reading up on what crops you’re growing and if they have any specific mulch requirements.
If you’re laying on mulch to regulate your soil’s internal temperature, your soil must be already at the optimal temperate for the companion plant. This is because mulch keeps the soil’s temperature regular by essentially “locking in” whatever the soil’s current temperature is.
What I mean by this is: take tomato plants, for example. Tomato plants thrive on a warm soil temperature of about 70° F. If you intend on using mulch to keep that soil warm, you must wait until the earth is at the target temperature before laying down mulch. If I mulched around my tomato plant when the soil temperature was 55° F, then the soil would stay somewhere in that range, and my tomatoes wouldn’t reach their full potential.
Keep mulch about 2 to 3 inches away from the base of your plant, do not pack on mulch around the bottom of your plant like a “volcano.” The reason for this is that if the mulch happens to grow bacteria, it maintains a safe distance away from the plant’s main stem, reducing the chance of infection reaching the plant.
As a whole, including mulch in your gardening repertoire is packed with benefits. Whether mulch is used for temperature control, moisture retention, pest prevention, or weed deterrent, mulching is necessary for growing unique plants. I used to grow vegetables without mulching, and I can honestly attest that adding mulch to my garden has saved me so much time and energy by not worrying about constant watering or weeding.
However, with all the benefits mulch provides for your garden, you might run into tree seedlings in your mulch. Tree seedlings sprouting from mulch can be a tiresome nuisance in the park, but they can easily be remedied with simple solutions. Luckily, learning to get rid of tree seedlings in mulch has never been easier. I hope using these skills and tips in this article will help improve the quality of your garden!
Campbell, Lindsay. “A Guide to Homemade Mulch.” Modern Farmer. https://modernfarmer.com/2020/07/a-guide-to-homemade-mulch/
“Choosing and Installing Mulches.” The University of Florida. https://gardeningsolutions.ifas.ufl.edu/care/planting/mulch.html
Erler, Emma. “Garden Mulches [fact sheet].” The University of New Hampshire. https://extension.unh.edu/resource/garden-mulches-fact-sheet
Johnson, Doug. "How to Kill Tree Seedlings." SF Gate. https://homeguides.sfgate.com/how-to-grow-healthy-flowers-indoors-13768649.html
Smyth, Danielle. “How to Stop Saplings From Growing in the Garden.” SF Gate. https://homeguides.sfgate.com/stop-saplings-growing-garden-42094.html
“Will Plants Grow Through Mulch?” Peppers Homes & Gardening. https://peppershomeandgarden.com/will-plants-grow-through-mulch/