Answer: There are only a few guidelines to remember in raised bed construction: Keep the beds narrow and match their length to the site and the watering system. A north-south orientation is best for low-growing crops, allowing direct sunlight to both sides of the bed. Beds that will contain taller crops such as pole beans, trellised peas or caged tomatoes might do better on an east-west axis. Thus, lower-growing crops could be planted on the south side of the bed and still get full sun. Avoid the use of creosote or pentachlorophenol-treated lumber for bed frames. These chemicals can leach out and injure plants. Use pressure-treated lumber, redwood, cement block or brick, and be aware that the cement in block will raise soil pH over time. Even if the soil is heavy clay, at least one-third of the volume of the bed's root zone should consist of existing soil. There are a lot of good minerals in clay and by loosening it up with one-third compost or peat and one-third coarse sand, it will make a good growing medium. Add a little garden fertilizer and test the soil after the first crop year. Raised bed possibilities are endless. Beds elevated 2 feet or more offer the promise of gardening without bending and can have benches built on the sides for even more convenience. Because a bed warms up quicker than the ground, it can easily double as a cold frame by covering it with a lightweight clear plastic cover. Imagine being able to start plants early in beds with covers and never having to transplant them! Supports for poles, cages and trellises can be mounted to the frame for longer life and ease of installation and removal. Hope this information convinces you to try raised bed gardening!
Q&A Library Searching Tips