There are many reasons why a gardener might want to utilize raised beds. One of them – better drainage – became very apparent last week when more than two inches of rain fell over a short period of time. Other reasons include: raising the soil even a few inches makes it easier on your back for weeding and harvesting; the soil warms faster in spring allowing for earlier planting; the soil is never stepped upon so it doesn’t become compacted; it is easier to exclude pests; you can plant more in less space; you don’t step on or trip over plants; and raised beds make for a beautiful and tidy garden.
Raised beds range from casual to formal, from inexpensive to costly, and from on-ground to waist high.
The easiest way to construct a raised bed is to rake soil from pathways into long mounds. Voila! – raised bed. Soil can also be brought in to create the mounds.
Most people prefer an edge on their raised beds. Materials include wood, stone, galvanized steel, straw bales or plastic lumber. For wood, choose cedar, redwood, or untreated landscape timbers. Avoid railroad ties and treated lumber for beds that will grow food as chemicals in the lumber will leach into the soil and be taken up by the roots of food crops.
Cinder blocks laid end to end make a good edging. Large field stones or piled bricks make a more casual edge. For the non-DIYer there are many raised bed kits on the market. There will still be some assembly required.
Raised beds can be any shape or size but they should not be more than 48” wide so the gardener can reach into the middle from both sides.
If the bed is raised off the ground don’t use soil dug from the ground. A lighter weight soil mix is needed, so choose a bagged product labeled garden soil, potting soil or raised bed soil. If you go the off-the-ground route, be sure the bed is constructed so that the soil is at least 12” deep for most plants, and 24” deep for tomatoes, peppers or kale.
When planting, there is no need to allow space between rows. Let’s say the seed packet says to place seeds 4” apart within rows and to allow 2’ between rows. That 2’ is for walking space which is not needed so seeds can be spaced 4” apart in every direction.
Is a raised bed in your future for next year? You can construct it this year right over your existing lawn by laying large pieces of cardboard or thick layers of newspaper over the grass and weighting it down with rocks or bricks. Throw grass clippings, weeds that haven’t formed seeds, leaves and anything else you might throw into a compost pile into the area all season. Add soil this fall or next spring and you’ll be ready to go!