Raised bed gardening: Try it, you’ll like it

A raised bed gar­den by def­i­n­i­tion is sim­ply one that is ele­vated off the ground. The bed can be solid to the ground and con­structed with sides made of wood, brick, or other mate­ri­als. The bed can sim­ply be a berm with no per­ma­nent edges. Or, the bed can be com­pletely ele­vated off the ground so that a chair can be placed under it. How you design your raised bed gar­den depends on your avail­able resources, where you are putting it, and how you intend to use it.

One of the pri­mary rea­sons that peo­ple choose to have a raised bed gar­den is to have improved soil. Much of Delaware County has hard clay soils. This is espe­cially true in new hous­ing devel­op­ments when top­soil is removed and replaced with the clay dug out for the foun­da­tion. Also, a raised bed gar­den is desir­able if a gar­den is being located on a site, such as an aban­doned city lot, where the soil may be con­t­a­m­i­nated. Bill Daw­son, Grow­ing to Green Pro­gram Coor­di­na­tor for the Franklin Park Con­ser­va­tory, rec­om­mends in these instances that for com­plete safety you replace at least 18” of soil to let the roots thrive but not grow into the native soil.

Typ­i­cally, a raised bed gar­den has a per­ma­nent bor­der. Jim White, a Delaware County Mas­ter Gar­dener intern, recently built three raised beds in his yard. Two are enclosed in wood frames, and the third is con­structed from bricks. He lined the bot­tom of each bed with a weed mat and then used pre­mium organic gar­den soil from a local sup­plier to fill the frames.

Every­one I talked with rec­om­mended that you limit the width of a raised bed gar­den to about 4 feet, so you can reach to the mid­dle of the gar­den from either side with­out stand­ing on the bed and com­press­ing the soil. The length of the gar­den can vary and depends on the space you are fill­ing and the mate­ri­als you have available.

Some of the ben­e­fits you get from raised beds include much bet­ter drainage than you have in native clay soils. They also warm up ear­lier in the spring, allow­ing you to extend the grow­ing sea­son. Jim White has had a gar­den in his back­yard for many years, but he says that by con­vert­ing it to raised beds his gar­den is bet­ter than ever. This is in direct con­trast to the frus­tra­tion that many local grow­ers with­out raised beds have expe­ri­enced due to the cold, wet spring weather. How­ever, since these beds do have bet­ter drainage, it is nec­es­sary to water them thor­oughly to avoid shal­low root sys­tems. Liz Coverdale, hor­ti­cul­tur­ist at the Franklin Park Con­ser­va­tory, reminds us that we don’t want “wimpy plants” that will not stand up dur­ing the hot days of summer.

Raised beds are ideal for peo­ple with lim­ited phys­i­cal abil­i­ties. Sarah Ritchea, of the Her­itage Health Day Cen­ters, coor­di­nates a pro­gram at their facil­ity on Dublin-Granville Road in Colum­bus, mainly for older adults. Pro­gram mem­bers have the option to have their own small indi­vid­ual raised veg­etable gar­den. They get to choose what to plant. Then they main­tain the gar­den on their own, or with assis­tance as needed. Sarah says that gar­den­ing is one of the more pop­u­lar activ­i­ties at the cen­ter. It’s ther­a­peu­tic, and “they like to get their hands dirty.” Fre­quently it brings back fond mem­o­ries. Raised beds that are solid to the ground are pre­ferred by Sarah for veg­etable gar­den­ing, even for peo­ple con­fined to wheel­chairs. Raised gar­dens that are con­structed on legs so that a chair can go under them have more lim­ited use, as the beds are shal­lower and dry out more quickly, so veg­eta­bles can­not develop strong deep roots.

Accord­ing to our con­tacts, despite the time and expense of prop­erly installing raised beds, the ben­e­fits far out­weigh the costs. They are an excel­lent alter­na­tive when there is a drainage issue. They also allow you to cus­tomize the soil so plants, such as blue­ber­ries, which require acidic soil, can thrive in your gar­den. The grow­ing sea­son is longer as the soil is warmer, and it is eas­ier to work, since it is higher up and not com­pacted by walk­ing. Raised beds that are solid to the ground are the most ver­sa­tile and the eas­i­est to main­tain. You can hire a land­scap­ing firm to build a bed or do it your­self. More infor­ma­tion can be found online at Ohioline.edu in The Ohio State Uni­ver­sity Fact Sheet HYG—1641–92. Resources are also avail­able at your local nurs­ery, in a book­store or your local library. Or you can con­tact the Delaware County Mas­ter Gar­dener Helpline (740–833-2030) week­days for help in get­ting started.

Nancy F. Traub is an OSU Exten­sion Delaware County Mas­ter Gar­dener Volunteer.

Posted by Andrew Tobias on Jul 8 2011. You can follow any responses to this entry through the RSS Feed. Comments can be made below.