A Beginner's Garden: Soil Layers and Planting Your Raised Bed

Learn how to make simple raised bed frames here:
"A Beginner's Garden: Make a Raised Garden Bed the Easy Way"

Till a 3 ft x 5 ft area of ground. Example bed frames are 2 ft x 4 ft; the oversize gives you some extra room to position the frame correctly. Place the frame over the tilled area, and scoot it into place. Check the top edges with a level, and adjust the placement so it is level. For aesthetic reasons, square the frame with any nearby buildings, walls or fences.

Add some peat, and mix it into the tilled ground soil in the bed frame. Then add some compost to fill the bed, and mix it into the top few inches. I add the soils in layers this way, because I want the soil below the bed to be loosened. The peat will condition the deep soil, making it better for deep roots. I add compost last, so it is in the top several inches of the raised bed, with some of the peat mixed in. Most of the feeder root activity of plants I will grow will be in the top few inches, so there is no reason to use compost deeper where it will be wasted. Rain and irrigation will dissolve nutrients in the compost, anyway, and they will trickle down. If I plan on growing root crops in the raised bed, I add a bit of bone meal with the peat in the middle layer.

Peat is optional, of course. Peat may raise the soil acidity, so you might want to skip it and just mix in compost only. It depends on your soil pH to begin with, and what you will plant in the bed.

Rake or smooth the soil in your raised bed so it is level. If the soil is not level, water runoff will pool in the low area, and seeds and plants may wash out of place.

Cover your raised bed with clear plastic sheeting and you can use the bed to start seedlings. I plant cabbage, broccoli, cauliflower, and Brussels sprouts seeds in rows about 4 inches apart when the weather warms enough, usually by mid to late March in southern Indiana. The seeds are up and growing in 7 to 10 days under plastic. They are typically ready to transplant into the garden by mid to late April. Raised bed seedlings are more robust than seeds started indoors, with much better root systems.

Plants started indoors must be hardened off before they can be transplanted into the garden. Hardening off means the plants are exposed to the outdoors for increasing lengths of time over a few days so they aren't overwhelmed by bright sun, wind, and normal outdoor stresses that were absent inside. The seedlings I start in a raised bed can go straight into the garden, since they are already acclimated.

Raised beds require careful moisture monitoring. They dry out quickly, and may need daily watering. I find that there is less moisture loss as the plants grow and the foliage shades the soil. Install a drip irrigation system to make watering easy if you have permanent beds.

See related slideshow: "Use Your Raised Bed as a Greenhouse or Coldframe"
See Related Article: "A Beginner's Garden: How to Turn Your Raised Bed into a Greenhouse or Coldframe"

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Personal Experience