There are several ways to get rid of grass, whether you're reducing the size of your lawn or making room for a new planting bed or garden. The two basic approaches are to kill the grass or to remove it. Both can be done organically, without the use of chemical herbicides. Removing the grass is harder physical work, but it's generally faster, and it gets rid of the grass layer, lowering the height of the ground. Killing the grass organically involves smothering it with a material. This is the easiest method if you plan to use the area as a mulched bed with shrubs.
Removing Grass With Rototilling
You can rototill a lawn area that you wish to convert into a flower bed. Always call the call-before-you-dig hotline before using a rototiller. A large machine is preferable for this operation since you'll want more power than a small garden tiller can offer. But it's not as simple as it sounds. The stolons will remain in the soil after you're done tilling, so you'll have to cover the tilled soil with landscape fabric or another material to prevent new grass shoots from sprouting up. Otherwise, you'll find yourself pulling grass shoots for a long time.
Spreading landscape fabric over the ground after rototilling, then covering it with mulch, is a way to get rid of grass that works best in shrub beds, where you don't need access to much of the soil under the landscape fabric. You can simply "pocket plant" afterward. This means making holes in the landscape fabric only where the shrubs are to reside. Simply cut an "X" or a hole in the fabric large enough to dig your hole for each plant, leaving the rest of the fabric intact. Once the shrubs are planted, cover the entire area with an attractive mulch.
Removing Grass by Digging
The most thorough way to get rid of grass is to physically remove it, roots and all, using a spade or shovel. Alternatively, you can use a sod cutter, but in any case, you have to pick up the chunks or strips of grass and shake off the soil. If you skip this step and simply discard the grass, you'll lose precious topsoil, and the waste will be extremely bulky and heavy (you're essentially throwing away tons of valuable dirt).
Therefore, a sod cutter doesn't save you much time and isn't worth the expense and hassle, unless you're planning to replace the topsoil layer with sand or new soil for some reason.
When digging up the grass, dig down just far enough to get all of the fibrous grass roots. You can cut the grass into 1-foot-wide strips, using a flat spade or an edger, then dig under the strip with a shovel to remove to sod layer. Finally, shake out as much topsoil as possible, and discard or compost the grass.
Killing Grass by Covering It
A less labor-intensive way to get rid of grass organically involves laying down various kinds of materials atop the unwanted vegetation. By far the most popular method is to lay down newspaper as a smothering agent, but you can also use a tarp or black or clear plastic. Consider the pros and cons of each method.
Presumably, you'll be able to get your hands on a sufficient supply of newspapers for free. If you haven't saved up a stash of your own newspapers, you can always check with friends looking to clean out their attics or with recycling centers, etc. Another pro with newspapers is that they break down into the soil over time, meaning there's nothing to clean up after you've accomplished your mission. Furthermore, if you wish to plant landscape shrubs in select areas while waiting for the rest of the lawn to die, just dig out the sod in those areas and do your planting (you can skirt those spots easily enough when laying down the newspaper, which is a flexible material).
The newspaper may be free, but you're unlikely to get away with paying nothing at all for this project. You'll want to cover your newspaper with mulch, and that will probably cost you some money. But the mulch also breaks down, returning nutrients to the soil, an added benefit. The main disadvantage of newspapers is that laying out the papers is more work than covering grass with large sheets of plastic or a tarp.
A tarp can also be used to choke out the unwanted lawn. You'll want to cover it with mulch for three reasons:
- To hide the tarp for aesthetic reasons
- To hold down the tarp, so that it doesn't blow
- To protect the tarp against wear and tear from foot traffic
As you can well imagine, the pro of this method is that it's fast and easy. But a major con is that, unlike landscape fabric, it's not advisable to cut through a tarp and pocket plant, for two reasons:
- A tarp is not permeable and therefore will not allow air and water through to the soil.
- Cutting through a tarp will compromise the material and cause it to shred, so you'll end up with a gaping hole where you wanted just a small one.
Consequently, while a tarp will smother the lawn, you have to wait until after it has finished doing its job (and after you've removed it) before you can plant the area, unless you use container gardens or raised beds.
Black plastic represents something of a compromise. It doesn't have the permeability of landscape fabric, but, if you're careful, you can cut through it and pocket plant (unlike with tarps). Precisely because it's impermeable, it acts as a smothering agent (like tarps), so there's no need to rototill first. As with the other materials, it should be covered with mulch. Other cons of black plastic are that it's not biodegradable, and the high temperatures it generates can kill beneficial organisms in the soil.
In hot climates, one way people sometimes use to get rid of grass is to cover it with clear plastic. Here, though, you're not smothering the lawn, you're giving it a deadly sauna treatment. Water first, then cover with the clear plastic, securing it (with scrap lumber, etc.) at the edges. Periodically apply more water. Such soil solarization is also employed in scrubby, weedy areas when you're trying to start a garden from scratch, as the hot temperatures will kill weed seeds.
A con of this approach is that you can't grow plants in the area at the same time. And as with black plastic, you may well end up killing some of the microbes that benefit the soil.