Any weeds that grow through mulch are easy to pull because the soil remains loose. Photo by Saxon Holt.
The frequency and timing of your fertilizing efforts are also crucial to healthy lawns. Both vary depending on your lawn type and the length of your growing season. Most northern lawns need only one or two applications of fertilizer annually—once in fall and sometimes a second time in spring. Southern grasses might require three feedings—early to mid-spring just after the grass greens up, early summer and again in early fall.
Preemergence herbicides, such as those containing oryzalin or trifluralin (look on the label for these chemicals), or nontoxic corn gluten meal, kill weeds just as they germinate and will not eradicate established weeds. For a preemergence herbicide to be effective, you must apply it to soil cleared of visible weeds; also, you have to water most of these herbicides into the soil.
Left unattended, weeds will quickly fill in unplanted areas and any open ground around plants. Mulch spread over the soil surface blocks the sunlight most annual weeds need to take hold. Weeds that do sprout are easy to pull because soil beneath mulch remains loose and moist. Coarse chipped or shredded bark is a good choice for large areas between trees and shrubs because it decomposes slowly and doesn’t easily blow away. For paths, a thick layer of sawdust provides good weed suppression because it depletes nitrogen in the soil.
As with most types of prevention, discouraging weed seeds from sprouting requires some extra time now so you can save a lot of time later.
Deprive Weeds of Water.
Frequent, light watering causes shallow roots and helps annual bluegrass, crabgrass, chickweed, sedges and other weed seeds germinate. If you water too little, the lawn suffers while spotted spurge, Bermuda grass, quackgrass and other weeds adapted to drier soil thrive. Instead, provide your lawn with infrequent, deep soakings. Lawns need about 1 inch of water per week. Set an empty tuna can on the lawn to determine when you have applied 1 inch of water.
Too little fertilizer can lead to sparse lawn that loses the competition with weeds. Too much helps nurture certain weeds, notably annual bluegrass, Bermuda grass and crabgrass. Strike a balance by following the application rates on the package. And use a fertilizer with a high percentage of controlled-release nitrogen, such as sulfur-coated urea, ureaform or IBDU. These provide a slow, steady nutrient supply.
True Temper Hardware Box 8859 Camp Hill, PA 17011 800/393-1846 Scuffle hoe.
Yes, you can. Synthetic landscape fabrics provide a physical barrier to weeds yet allow air, water and nutrients through to plant roots. Spread the fabric over bare soil around trees and shrubs; overlap several inches of fabric at the seams. Anchor the material with U-shaped metal pins, then conceal it with 1 to 2 in. of mulch, such as stone or bark chips.
You can get in-depth information on drip irrigation from the Irrigation and Green Industry Network in the “Where to Find It” section.
Check the label to determine if it is safe for use around the kinds of landscape plants you have and effective against the weeds normally present.
Spread Landscape fabric and cut it to fit around plants. Photo by Saxon Holt.
Controlling weeds is a fight you can’t win entirely because they always grow back. But you can keep weeds under control by depriving new ones of the conditions they need to take root in the first place. Let’s look at how to prevent weeds from growing.
Think it’s an overstatement to call it the war against weeds? Here’s what you’re up against.
Denman & Co. 401 W. Chapman Ave. Orange, CA 92866 714/639-8106 Ball weeder.
Fertilize Enough, but Not Too Much.
Raindrip Inc. 2250 Agate Ct. Simi Valley, CA 93065 www.raindrip.com 877/237-3747 Request the free “Drip Watering Made Easy” guide.
This Preemergence herbicide, made from corn gluten, is nontoxic. You can safely use it near all of your vegetables as well as around ornamental plants. Photo by Saxon Holt.
Weeds can’t survive without moisture. In areas with little or no summer rain, drip irrigation or soaker hoses help prevent weed seeds from sprouting by depriving them of water. These systems deliver water to the root zone of plants at the soil level. The soil surface and area surrounding the plants stays relatively dry. In contrast, overhead sprinkler systems spray water over the entire soil surface and supply both garden plants and weeds with water.
You can also use landscape fabrics to control weeds under decks and in pathways (spread over the excavated soil base before you add gravel or sand). A 3×50-ft. roll of landscape fabric, such as the Typar shown below, costs about $10. The fabric is also available in 36-in. die-cut circles (about $3 each) for installing at the base of trees.
Photo by Saxon Holt.
Irrigation & Green Industry Network 916C N. Formosa Ave. Los Angeles, CA 90046 www.igin.com 323/878-0318.
A single redroot pigweed is able to produce up to 30,000 seeds in a season. And those seeds can remain alive in the soil for 70 years waiting to sprout and overrun your perennial border at any time.
How to Mulch Over Weeds.
In the process of trying to eliminate weeds, people often make mistakes that lead to more weeds. Here are the most common:
Tips on how to keep weeds out of the garden, add the right amount of mulch over weeds, and 6 mistakes to avoid to keep your garden weed-free.
Mowing too low weakens turf by reducing the ability of a grass leaf to produce enough nutrients. It also lets light hit the soil surface, which helps crabgrass and goosegrass seeds sprout and grow. Check with your local extension service for the recommended range of mowing heights for your grass type. Then mow at the highest level—usually between 2 and 4 inches.
Lee Valley Tools Ltd. Box 1780 Ogdensburg, NY 13669-6780 800/871-8158 Telescoping Crack Weeder.
(For those of you who already have weeds attacking your yard, read our article on How to Get Rid of Weeds.)
Primus Box 186 Cherry Valley, IL 61016 815/332-5504 Weed flamer.
Apply a 2- to 4-inch layer of organic mulch over the entire surface of the black plastic weed barrier. Spread the mulch over the edges of the weed barrier so the black plastic doesn’t show.
Rake the area smooth and remove any old mulch, rocks or debris that could poke a hole in your weed barrier.
Overlap the strips of black plastic weed barrier so weeds can’t sneak their way through the edges of the material.
Cut small “X” shapes into the weed barrier if you want to plant new plants in the area before laying the mulch. Dig a hole in each “X” shape and place one plant inside each hole.
Pull up any weeds that are already growing in the area you want to mulch. Use a trowel to help you remove the roots of the weeds, which will decrease how many try to grow back.
Things You Will Need.
Spread a layer of black plastic weed barrier over the planting area. If you already have plants growing in the area, cut holes in the black plastic to fit over them.
Weeds are the enemy of gardeners around the country. These pesky plants decrease the beauty of your yard and rob vital moisture and nutrients from your flowers, vegetables and lawn. Mulch helps minimize weeds but also retains more moisture and helps moderate the temperature of your soil. The trick to keeping weeds from growing through your mulch is to put a layer of weed barrier underneath.
Use several layers of old newspaper in place of black plastic weed barrier if you want a more environmentally friendly way to reduce weed growth through your mulch. Lay the newspaper down and cover with a 2- to 4-inch layer of organic mulch. You’ll have to replace the newspaper and mulch more often, however, because the newspaper will biodegrade over time. Fabric weed barriers are another option, though they aren’t always as effective as plastic in preventing weeds from growing.
Black plastic weed barrier.
Don’t use clear plastic weed barriers because they aren’t as effective as black plastic. Clear plastic lets more sunlight in, which can encourage weed growth. Don’t use plastic weed barriers around trees and shrubs because it prevents their roots from getting adequate water.
In Columbia, Missouri Voss Landscaping uses and suggests triple-shredded hardwood mulch to prevent weeds from growing. Higher quality mulch typically contains larger materials and chunks in it. If used liberally, about three inches deep, your high-quality mulch should prevent any future weeds from surfacing.
Another sure-fire way to prevent weeds when planting your bed is to employ the use of a landscaping fabric. Landscaping fabric is a thin textile you can purchase at most local garden stores and is designed to prevent the growth of weeds by blocking sunlight to them.
Mulch is great for your landscaping needs — it can help to preserve moisture, improve the fertility and health of your soil, and add some aesthetic appeal to your front or backyard. Another main reason mulch is purchased is to prevent the growth of pesky weeds from terrorizing your plants. However, why is it the case that sometimes even after mulching that weeds can still grow through?
Pro Tip: Use a dyed mulch to have your mulch bed retain its color all year long!
There are several reasons why weeds may be breaking through your mulch bedding. Follow our tips below to discover the reasons why and the best ways to prevent them from showing up again in the future!
Purchase High-Quality Mulch.
One of the benefits of mulch is that it prevents weeds from growing in the first place. If weeds are piercing through your mulch-bed, it may be the case that you are using a cheaper or low-quality mulch. These are typically made with grass clippings, straw, or leaves as opposed to wood chips, bark nuggets, and sawdust.
If you already have planted your mulch and are seeing weeds growing through it, this could be for a number of reasons. It could be that your mulch is low quality, your bed isn’t thick enough, or your mulch is older and breaking down. Regardless of the cause, you’ll want to start by manually dealing with the problem.
Once you have planted all trees, shrubs, or bushes in the area you will want to cut the fabric to size before you begin the mulching process. Since the material is relatively thick it should be easy for you to cut and shape it to fit perfectly in the location. Once in place, you’ll want to spread mulch as normal and cover the fabric completely. This will help to prevent weeds for up to 5 years depending on the type of landscaping fabric you purchased.
First, pull all the weeds you can find by hand that is directly residing in the area of your mulch. Any additional weeds that are exposed around the area should also be sprayed with a common herbicide or weed killer that contains glyphosate (most common weed killers contain this). Finally, you’ll want to apply a granular pre-emergent product to the mulch bed to prevent future weeds from growing. You can purchase a pre-emergent granular product at your local garden store.
Want to ensure your mulch bed is installed properly? Leave it up to the experts at Voss Landscaping & Tree to ensure your mulch is giving your trees and shrubs the most benefit. Our expert landscapers offer a wide array of landscaping services and will always apply the highest quality mulch!
Having staff that is knowledgeable and passionate means that we understand the importance of doing the job the right way. Contact Us today w ith any of your landscaping needs!