Manage your garden weeds through a few easy steps by adding mulch and a layer of newspaper to help prevent those pesky weeds from coming up. How Can I Keep Weeds From Growing in Mulch? Applying mulch every spring makes sense on several levels. It helps enrich the soil and helps retain moisture during the dry summer months. But the Weed control is one of the primary reasons for applying mulch, yet pesky weeds may persist, even through a carefully applied layer of bark chips or pine needles. What should you do if you've got weeds coming up in mulch in spite of your best intentions? Click here.
How to manage garden weeds with mulch
Managing garden weeds is a challenge all gardeners face, but Skip Richter, Texas A&M AgriLife Extension Service horticulture agent, Brazos County, and host of Garden Success, KAMU FM/HD-1, offers some advice to keep the weeds at bay that can be easily implemented with a bag of mulch and a few newspapers.
Mulch can help prevent weeds by. blocking sunlight for germination. (Texas A&M AgriLife photo by Sam Craft)
The importance of removing weeds
A weed is classified as any unwelcome plant in your garden. It could be an invasive plant, or just a volunteering plant of some sort, but if it is not something you want to grow in your garden area, then it may be considered a weed.
Aside from possibly not adding any beauty or benefit to your garden, weeds can take away water, nutrients, soil and sunlight from plants you wish to thrive in your garden area. Weeds may also harbor plant viruses or even attract pests that could then move on to your garden plants. As weeds grow larger, removing them by hand pulling or hoeing can disturb the roots of your garden plants.
Without proper maintenance or prep work, gardeners may find themselves pulling weeds year-round, when a few steps at the beginning of the season could significantly reduce or even eliminate your days of weed pulling all together.
Skip Richter explains how placing newspaper down before mulch provides and even sturdier barrier for weeds. (Texas A&M AgriLife photo by Sam Craft)
“When you put four to six sheets of newspaper down on the surface of the soil and then throw a mulch of leaves, dried grass clippings, compost, shredded bark or other organic materials on top of that, it will block out most weeds for the remainder of that particular gardening season,” he said. “It lasts about three or four months.”
A tip to keep in mind as you lay down the newspaper is to wet it as you lay it so that it does not blow away. Richter likes to lay the newspaper four to six sheets at a time and overlap it by a few inches. When you get to a plant, split the page, and lay the paper on either side of the plant. Then spray the newspaper with water and place the mulch over top.
After you have placed all the newspaper down with a mulch over the top, there should be no newspaper visible. The “mulch-over-newspaper” technique will keep weeds out, so you shouldn’t have to come back and do any more weeding any time soon. If a weed does appear, it may be due to a hole in the newspaper, so simply pull back the mulch, remove the weed and lay another piece of newspaper over the hole. Then cover it with the mulch.
The newspaper and organic mulch technique works well before weeds germinate but can also help capture lost ground by smothering young weeds before they get too large. It helps to wet the weeds and soil before laying the newspaper and mulch. Those young weeds will die and decompose under the newspaper cover, releasing their nutrients back to the soil.
For larger areas where you are not growing plants but just want to keep down the weeds, you can take it up a notch and use large sections of cardboard covered with leaves or even shredded branches to create a longer term weed block over the soil.
If mulching and weed control were helpful in the planning of your garden, be sure to look into raised garden beds, starting from seeds or transplants as well as how to choose the best fertilizers for your gardens.
For further information on growing vegetables, visit the Easy Gardening Series, or view the information on planting vegetables to get more on seeding and transplanting.
For more information on gardening, check out the Aggie Horticulture website, where there’s a wealth of free publications on all aspects of gardening from Texas A&M AgriLife.
Laura Muntean is a communications specialist for Texas A&M AgriLife Communications in Bryan-College Station. She is responsible for media relations and writing news releases and feature articles based on science-backed information provided by experts throughout Texas A&M AgriLife.
How Can I Keep Weeds From Growing in Mulch?
Applying mulch every spring makes sense on several levels. It helps enrich the soil and helps retain moisture during the dry summer months. But the main reason most of us mulch is weed control. We faithfully lay down a couple of inches of mulch and cross our fingers that we’ve won the battle. But most of us aren’t so lucky: weeds almost always find a way to pop up, even in the most beautifully mulched landscaping. Why are weeds so hard to tame, and what can you do to stop them? Here are a few tips:
Why Do Weeds Grow In Mulch?
We all know how tenacious weeds can be. They thrive on the very same things your garden does: sunlight, water, and nutrients in the soil. Weeds take pretty much any opportunity to grow and aren’t picky about where they take root. As plant-based mulch decomposes, it provides an attractive, nutrient-rich environment for weeds to take root.
We often find weed seeds in old or contaminated mulch. Seeds can also get distributed by birds or wind into new beds.
How Can I Prevent Weeds in My Mulch?
Here are a few strategies for preventing weeds from popping up in your mulch:
- Apply the right amount. Mulch’s primary role in weed prevention is blocking the sunlight they need to grow. To make this happen effectively, you need to make sure it’s thick enough: we recommend 1.5 to 2 inches. But don’t over-mulch or your plants won’t get the air they need.
- Weed first, then mulch. When you’re preparing your bed, move aside old mulch, pull any weeds and then apply a layer of fresh mulch.
- Treat the soil with a pre-emergent herbicide before mulching.
- In some cases, especially around trees and shrubs, you can also lay down landscape fabric before mulching. It lets air and water into the soil but blocks weeds from growing.
- Edging around your mulched beds can also help discourage stray seeds from winding up in your mulch.
What’s the Best Mulch to Prevent Weeds?
For flower beds and landscaping, we like a chipped or shredded bark mulch with a relatively coarse texture. It decomposes relatively slowly and doesn’t blow away so it can do its job and keep sunlight from reaching the soil. Inorganic mulch (like stones or gravel) does an excellent job of preventing weed growth. However, it doesn’t offer the soil-improving benefits of organic mulch.
How Can I Kill Weeds in Mulch?
If weeds start popping up in mulch, we want to tackle them before they can seed and spread. If you’re pulling weeds by hand, make sure you get the whole weed, including the root. Applying a pre-emergent herbicide is also an option. One approach is a commercial weed-killer like Roundup, which contains the chemical glyphosate. Some gardeners prefer a more natural approach, using a mixture of vinegar, salt, and dish soap to kill weeds as they grow.
For More Effective Mulching: Hire a Pro
As experienced gardeners know, fighting weeds is a never-ending battle. They seem to pop up no matter what you do. But there are proven strategies for preventing them, and mulch is one of the best tools available. Working with a professional for your landscaping needs, including mulch application, is the best way to make sure your weed control program works.
At Epling, our experienced team knows which type of mulch to use in different locations. We apply just the right amount for each job, both for weed control and curb appeal. We have herbicide use down to a science and know which kind to use, both before and after mulching. This spring, put the focus on spending time outdoors with family and let our pros at Epling take care of the weeds.
Mulch Weed Control – Tips On Getting Rid Of Weed Growth In Mulch
Weed control is one of the primary reasons for applying mulch, yet pesky weeds may persist, even through a carefully applied layer of bark chips or pine needles. This happens when weed seeds are buried in the soil or are distributed by birds or wind. What should you do if you’ve got weeds coming up in mulch in spite of your best intentions? Keep reading for a few helpful tips.
Getting Rid of Weed Growth in Mulch
Manual Mulch Weed Control
Mulch acts as physical barrier against weeds, but it must block sunlight in order to be effective. If you notice weeds coming up in mulch, you may need to thicken the layer as blocking light generally requires at least 2 to 3 inches (5-7.6 cm.). Replenish mulch as it decomposes or blows away.
How to Kill Weeds in Mulch with Herbicides
Other than hand-pulling, mulch is probably the single most important means of weed control. However, mulch works best when used as part of a multi-pronged approach along with pre-emergent herbicides.
When used correctly before weeds sprout in early spring, pre-emergent herbicides are one effective way to prevent weeds coming up in mulch. They won’t, however, do anything for weeds that have already sprouted.
To stop weeds in mulch with pre-emergent herbicides, begin by raking mulch off to the side, then hoe or pull any existing weeds. Apply the product, following manufacturer directions to the letter. Pay attention to the label, as some plants don’t tolerate certain types of pre-emergent herbicides.
Replace the mulch carefully, being careful not to disturb the just treated soil. At this point, you can provide extra protection by applying another layer of herbicide over the mulch. A liquid herbicide works best because it adheres to the mulch instead of falling through to the soil.
A Note about Glyphosate: You can use glyphosate to stop weeds in mulch, but this approach requires extreme care because glyphosate, a broad-spectrum herbicide, will kill any broad-leaved plant it touches, including your favorite perennials or shrubs. Apply glyphosate directly to weeds, using a paintbrush. Be extremely careful not to touch nearby plants. You can also protect plants by covering them with a cardboard box while you’re applying the herbicide. Don’t remove the box until the treated weeds have time to dry completely.
Preventing Weeds with Landscape Fabric
If you haven’t applied mulch yet, landscape fabric or weed barrier cloth is a safe way to block weeds while still allowing water to pass through to the soil. Unfortunately, landscape fabric isn’t a perfect solution because some determined weeds will push through the fabric, and those weeds will be extremely difficult to pull.
Sometimes, good old hand-pulling is still the most effective way of getting rid of weed growth in mulch.
Note: Chemical control should only be used as a last resort, as organic approaches are safer and much more environmentally friendly.