For the urban gardener, the existing vegetation is usually turf or a mix of turf and weeds. In rural areas it may be anything from pasture grasses to a patch of weeds, brambles and wildflowers.
You have a choice of four methods to remove the existing vegetation – Chemical, Mechanical, Manual, or Mulching. They all have advantages and disadvantages. Choose one that works best for you.
You have probably already figured out that I don’t support the chemical option, which would mean using herbicides. There is plenty of information on using herbicides out there on the web and at your local garden center if you decide to use this option.
The so-called “organic” herbicides such as 20% “vinegar” or “vinegar” combined with other components such as orange oil or soap would never be an option to remove vegetation prior to bed prep. They are designed to deal with very young, annual weeds. They cannot handle perennial weeds or even mature annual weeds. I am not much of a fan of these products either, to tell you the truth.
Mechanical removal can be done with a rented sod cutter or roto-tiller. These methods are designed for large areas only and would be difficult for a small bed.
Deciding which one to use may simply be a matter of what equipment you have available in your area, and which one you are comfortable using. But the type of turf you are dealing with is also a consideration.
Tilling to remove existing vegetation will work if your area is St. Augustine turf, a combination of turf and weeds, a mix of weeds, wildflowers & clumping grasses, or any turf other than Bermuda.
Bermuda grass is not so simple. A roto-tiller will do nothing except break Bermuda roots up into hundreds of new root cuttings. All of those little cuttings will take root, and you will have a months-long battle on your hands.
If you have Bermuda grass, or a mix of St. Augustine and Bermuda, use a sod cutter at the deepest setting possible to remove the roots and runners. You will have to be vigilant about any little pieces that get away from you. Remove them immediately if you see any sign of new growth.
For either machine, start by marking out the perimeter of the area with a landscape or chalk marker. These are available at home improvement and hardware stores.
Read about the Sod Cutter Method
Read about the Roto-Tiller Method
Manual removal entails a grubbing hoe and a strong back. I would recommend this for very small areas only because it is so labor intensive. It does get the roots of the existing turf and many of the small perennial weeds.
A grubbing hoe is often used incorrectly. The active motion should be in lifting the hoe, then just letting it fall at the proper angle. You do not have to hack at the surface. The head of a grubbing hoe is designed to cut through the soil at a fairly shallow angle and only an inch or two in depth with each pass. The blade of the grubbing hoe should not be driven straight down into the ground. Just lift, let it fall at a shallow oblique angle, move a few inches, repeat. It’s a really effective tool in the right hands.
After you have cut through the roots of the vegetation, rake it up and dump it in a wheelbarrow. Rework any spots you have missed, continuing this process until the area can be raked smooth.
Yes, mulching can be used to prepare an area for planting. It is not a weekend project. It can take as little as 90 days, but works better if you plan a season ahead.
To remove existing vegetation by mulching, begin by mowing or weed-whacking the vegetation as short as possible; then layer any clean organic material you can get your hands on over the entire area you wish to plant.
I generally use tree leaves, but you can use sheet materials such as newspapers or cardboard, compost, lawn clippings, chopped or ground yard waste, aged premium native mulch, or a combination of these materials. The idea is that the initial cover will be deep enough to smother the existing vegetation. The time it takes to die out and decompose varies by climate factors including rainfall and temperature.
After the existing vegetation is gone, you can either remove the material or further improve it and start mulch gardening. Earthworms will have multiplied like crazy in this environment and will have begun blending the decomposed grass and the organic material into the soil.
Dealing with perennial weeds
Once you have removed the existing surface vegetation, you may still need to deal with tough perennial weeds. Depending on the time of year, some of these may be dormant and out of reach of your herbicide at the time of application if you if you have gone the Chemical route. Most of them will have been removed with the Mechanical, Manual, or Mulching methods, but an occasional culprit will persist.
These “weeds” include things like tree seedlings and wild berry vines, which may need to be dug out. You can use a sharpshooter, but I like the speed and efficiency of the Sawz-All, the reciprocating saw. A reciprocating saw is designed as a wrecking tool for the construction trade. Thanks to battery-powered technology, they are now easy to use in the garden and I consider them a must-have garden tool.
To root out seedlings and deeper rooted perennial weeds, attach a long blade to the saw. It does not need to be a shiny new blade. Plunge the blade in the soil as deeply as you can and cut at an angle so you will sever the root below the crown. Easy-peazy.
Your bed is now ready for the next steps.