You may think that the only way to start a new vegetable garden is to laboriously dig up the sod and weeds to get down to bare dirt. But there's a simpler, no-till method of beginning a new garden called sheet mulching, sheet composting or lasagna gardening. With lasagna gardening, you smother out the existing vegetation with cardboard and then alternate layers of organic matter like leaf litter and compost to build up a new garden surface from scratch. Lasagna gardening requires some patience, but very little labor.
Cover the area where you wish to install a new garden with a single layer of corrugated cardboard. You can also use six to 10 sheets of newspaper. Avoid cardboard and paper that is glossy or printed with colored inks.
Wet the cardboard or newspaper thoroughly to prevent it from blowing away while you are working and to hasten decomposition later.
Spread an inch or two of compost or topsoil over the cardboard. Compost and topsoil can be purchased in 50-pound bags at any garden center, or you can get a bulk delivery from some landscaping companies.
Cover the compost or topsoil with an inch or two of dry, brown material, such as fallen leaves, dried grass clippings or shredded straw.
Continue alternating layers of compost or soil and leaf litter until you have built up the surface of the soil by 6 to 8 inches.
Wait three to 12 months for the cardboard and leaf litter to break down before planting in your new garden. You can plant into your garden immediately, but you will need to dig through the cardboard with a shovel. If you choose to plant right away, plant vegetable starts rather than seeds, and avoid planting any deep-rooted vegetables, such as carrots, for the first year.