Shrinking Your Lawn? Three Ways to Get Rid of Grass Before Planting Something Else

The perfect green lawn – once considered the hallmark of a responsible homeowner – has apparently undergone a radical change.

In at least some circles, a large, weed-free lawn is now referred to as a “biological wasteland” that could/should be used in more productive or environmentally friendly ways.

Warmer summers and periods of drought are putting additional strain on our traditional cool-season lawns, causing periods of mid-season browning and even leading to plant death.

Whether it’s reusing space for vegetables, creating a pollinator-friendly meadow or installing a rain garden to prevent stream flooding, the trend is toward reducing lawn space.

For those who decide to do this, the question arises of how to do it.

Neither method is particularly easy, but at least you have three main options for lawn removal. Late summer and early fall are the best times to do all of them.

Traditional Kill and Farm Method

This is the fastest way to transform your lawn into a garden, but it is also hard work.

The first step is to kill and/or remove the grass.

One option is to spray with kill-all herbicides such as glyphosate or glufosinate if you are a chemical gardener, or vinegar (acetic acid), ammonium fatty acid soaps, or various vegetable oil-based sprays if you are an organic gardener.

Once the grass has died back (usually within a week or two), the bed can be tilled, planted, and mulched. At this point, you can also mix compost into the bed if your soil is poor.

Check the label of the herbicide you are using for information on how long you should wait before replanting.

The chemical-free alternative is to go straight to tillage. While a large enough tiller can dig up the live grass, the downside is that it will leave clumps of grass that can re-root… unless you have the energy to remove and compost the clumps.

The second non-chemical alternative is to strip the sod with hand tools – or, for larger areas, by hiring a gas-powered sod cutter. Then you can dig or plough the bare soil, add compost and replant.

The dug-out turf pieces can be turned over on top of the prepared soil (i.e., root side up) and broken up to use up the decaying organic matter. The pieces can also be composted or used to patch bare lawn elsewhere (free turf).

If you are a planner, the turf can be killed by covering it with black plastic or garden fabric for at least a few weeks. Then the dead turf can be planted (if the soil is good) or ploughed over, improved with compost and replanted (if the soil is poor).

Tip: Whether you spray or cultivate, dig a 15cm wide strip around the perimeter of your new garden to separate the ‘leftover grass’ from your future garden.

Tip 2: Before you start any work, find out where your utility lines are or call Pennsylvania One-Call at 811 to mark them. Some internet and cable lines are only a few inches deep.

Sheet composting or the “lasagna” method

This method has recently gained popularity because it allows you to bypass the entire process of digging, plowing and using chemicals.

“Instead of removing existing lawn or weeds, layer composting builds new beds on top of them,” writes former Clinton County Master Gardener Coordinator Dr. Debra C. Burrows in a post on the Penn State Extension website.

Step one, he says, is to mow the grass short. Leave the clippings in place.

Step two involves covering the area with overlapping pieces of corrugated cardboard (flattened shipping boxes work well) or at least five-page sections of dampened newspaper.

Step three is to cover this layer with a two-inch layer of nitrogen-rich ingredients such as compost, well-rotted manure, grass clippings, used garden plants, or vegetable scraps.

Step four is to cover this layer with a two-inch-thick layer of high-carbon material such as wood shavings, dry leaves, sawdust, shredded paper, or pine needles.

“Repeat with layers of nitrogen and carbon until you reach a height of 18 to 36 inches,” Burrows says. “That may sound a bit high, but remember that the materials will shrink as they decompose. Cover the entire substrate with a layer of carbon, such as bark or mulch, as a top layer and lightly mist with a hose. The substrate is ready for planting vegetables or annuals when the materials have decomposed to the point where the individual components are no longer recognizable.”

If you stick with perennials, Burrows says you’ll need fewer materials. After adding a layer of cardboard or newspaper, he suggests a two- to three-inch layer of mulching material, such as leaves, grass clippings or shredded hardwood mulch.

“Once the layers are in place, all the gardener has to do is wait,” he says. “The process can take up to six months or more, so fall is the perfect time to start. It will break down over the winter, and the new bed will be ready for planting the following spring.”

York County Master Gardeners with Penn State Extension suggest adding a 4- to 6-inch layer of mulch, such as fallen leaves, grass clippings, wood shavings, bark and/or pine needles, over the cardboard or newspaper. (They recommend a 10-sheet layer of newsprint.)

York County police posted a five-minute documentary online showing the trial.

Suffocation from wood shavings

This is the simplest solution, but the challenge is getting the wood shavings and spreading them out in potentially huge quantities.

Wood chips (sometimes called “arborist chips”) are the leftover branches and stumps that a lumber company has chopped up after pruning or removing trees.

They never caught on because some people find them a bit “rough.” There are also rumors that they “steal nitrogen from the soil as they decompose,” and can also bring pests and plant diseases onto your property.

While none of these risks have been confirmed by research, the trick is to get the chips in the first place.

One method is to contact local lumber companies and ask if they will drop off a load the next time they are in your area. You may get one for free.

Another service is an online service called Chip Drop, which connects residents looking for shavings with lumber companies looking for places to dispose of them. It’s also free unless you want to increase your chances by making a donation.

The US Geological Service’s Bee Lab described its wood chip production process in an informational flyer for the 2024 Philadelphia Flower Show.

The lab says you shouldn’t put anything under the chips… just spread a twenty-centimeter layer directly on the grass, which doesn’t even need to be mowed.

“You can plant immediately, but if you have time, put down the shavings well in advance of your planned planting date so that the grass and weeds underneath have time to decompose,” the leaflet advises. “This will make planting easier.”

The roots of the plants should at least touch the soil below, and not be “swimming” completely in the chips. The mulch can be moved away from around the plants as they grow, and more mulch can be added in subsequent years to suppress weeds.

Dr. Linda Chalker-Scott, a Washington State University horticulturist and author of The Informed Gardener, is also a proponent of using wood chips to build new beds.

In general, he advises against composting cardboard, newspapers and sheets because they “tend to impede air and water flow.”

Her advice is based on a four-step process:

1. Mow the grass as close to the ground as possible.
2. Cover them with a layer of wood chips—at least 8 inches deep and up to 12 or 18 inches deep. “They’ll sink quickly, so you need to put enough down to maintain a depth of six to eight inches after a few weeks,” Chalker-Scott says.
3. Wait. The sod will decompose depending on temperature and water. Warm, moist conditions are ideal. After two to four weeks, pull back the mulch and see what’s underneath.
4. Once it’s easy enough to dig underneath, plant. “Be sure to push the mulch aside and plant into the soil,” says Chalker-Scott. “Replace the mulch to cover the disturbed soil and suppress weeds.”

Chalker-Scott says that while a layer of at least eight inches of wood chips can mean a lot of material to spread, it is easier and simpler than layering multiple materials, which is required for layered composting.

• Read George’s column on four ideas for reseeding your grass once it’s gone