“In a raised bed application, what should I use first before adding soil to prep the bed to reduce weeds and grass?” Question from Marlene or Stuart, Florida
Answer: There are several ways to stop perennial weeds from rising from the base of a new raised bed. You can either do the obvious– roll up your sleeves and completely desod and remove all weeds from the base of the bed–or you can place an organic cover at the base that will break down over time. If you choose to desod, you may also consider double digging below your beds to encourage deep rooting. (Click here to learn more about double digging.)
Raised Bed Organic Covers
The three organic covers that I recommend include either a layer of plain cardboard, black-and-white newspaper, or biodegradable burlap garden cloth. Any of these will work well if you provide full coverage. Place the cover of your choice at the base of the beds to stop weed growth, and then add enriched, raised-bed soil.
Raised Bed Soil Preparation
Raised bed soil should contain a mix of your own topsoil amended with lots of organic matter. Black Gold Garden Compost Blend, Black Gold Earthworm Castings, and an organic soilless potting mix, such as Black Gold Natural and Organic Potting Mix, are all good choices. Soil-to-amendment ratios depend on topsoil quality; good topsoil requires fewer amendments. In general, mix two parts topsoil to one part compost and one part soilless potting mix or earthworm castings. If drought is a problem in your area, add a 2- to 3-inch layer of compost along the soil surface to reduce surface water loss. I also recommend that you fortify your soil with a quality vegetable fertilizer.
To stop further weed encroachment, remove the grass from around your raised beds. Surrounding the beds with walkways covered with pebbles or organic mulches will look great and really help with weeds! (Click here to learn more about mulch solutions.)
Black Gold Horticulturist