Raised Bed Gardening

Advantages of Raised Bed Gardening

• Using raised bed gardening methods, plants get more sun and air circulation and they can make better use of water. You often can plant earlier and harvest later, because raised beds warm up early in the spring and stay warm later in the fall.
• Raised beds also make ideal places to grow plants that can be invasive in a regular garden – such as mints and horseradish. But ease and convenience is the benefit many gardeners appreciate the most. If you get a bad back and sore knees every year from gardening, a raised bed may put an end to those aches and pains.
• Raised vegetable beds are excellent for gardeners who have trouble with their backs and older people who don’t have limited flexibility. They are also excellent for people in wheelchairs or with other disabilities and
  those who don’t want to spend the summer on their knees in the garden.

Growing a garden is a challenge in many urban and rural areas because of soil conditions. Homes are not always built on soils with desirable agricultural characteristics, and many soils in urban areas have been modified adversely by home construction. Vegetable gardening can be difficult at best. Gardeners are soon discouraged by the difficulty of preparing an adequate bed because the soil dries so slowly in the spring. If the planting is finally made, crusting, clods, and collapse of plants during the summer prevent the bountiful harvest promised by the seed catalogs.

For centuries, crops in many parts of the world have been produced on modified soils in elevated growing areas between walkways. This "raised bed gardening" method has been adapted to smaller areas and may be the perfect solution to the problems of growing a garden at home.

At first this may seem like a lot of work. In fact the first stage usually is, however, it gets easier as the years go by and the advantages far outweigh the initial investment of time and money. It’s also more difficult to weed when soil is compacted, so with a raised bed, you can plant, weed and harvest without ever walking on the soil. Most gardeners find that raised beds are easier to maintain in the long run.

Soil improvement may be achieved by incorporating organic matter. Substantial quantities are required, so the organic matter should be readily available and relatively inexpensive. Sawdust, ground bark, leaves, or chipped pruning materials meet these criteria to one degree or another. If the organic materials are composted, so much the better, but this is not a necessity.

Other satisfactory materials, although more expensive, include planting mixes, which are sold by forest by-products companies, and animal manures, either alone or mixed with some kind of bedding material. See soil for more info.

Creating a raised bed usually includes a great deal of spading, possibly a multiyear process, but the following method permits great success in the first year after a fairly simple soil modification process.

Preparing raised beds

If the soil is compacted, an initial rototilling will be helpful, even if only 2 or 3 inches deep. Do not rush this step; wait until the soil is dry enough to pulverize and not turn it over in large chunks.

Step One
Spread a 2- to 3-inch layerof organic material over the garden’s surface. A cubic yard will cover 162 square feet 2 inches deep, so you will need 6 to 7 cubic yards per 1,000 square feet.

Unless you use a composted product, a mixture that contains manure, or a commercially fortified planting mix, you will need to supply nitrogen. Nitrogen is needed for organic matter breakdown. Broadcast one of the following supplemental nitrogen uniformly over the layer of organic material.

Step Two
Till (if you use a rototiller) to a depth of about 6 inches to mix in the organic matter. Spading will accomplish the same objective, but using a tiller will make the job less backbreaking and the results more uniform, especially in a heavy clay soil.

Step Three
Use a shovel and rake to shape the beds. They should only be about as wide as you can read, say 48 inches. Shovel the walkway area (14 to 16 inches wide) to a depth of 6 inches.

Add the excavated soil to the top of the beds. This creates a soil-organic mix about 8 inches deep, sufficient for adequate rooting of most vegetable plants.

When the elevated area is raked level, the natural slope of the soil will leave about 36 inches of flat planting space on top of the 48-inch-wide bed. Once the shaping is finished, keep traffic in the paths and do not compact your nicely prepared planting beds. Add sawdust or bark to the paths to prevent problems with mud.

The walkways between the raised beds may seem to be wasted space. However, when you see how much more you can grow on the beds, compared to what you did before, you will know the work was worth it.

"Retaining walls" are not necessary unless you want to create special shapes or use narrower walkways to fit your garden space. Boards, blocks, or railroad ties will hold the soil in place, but they also will create another place for slugs to hide and breed.

Planting and caring for plants using raised bed gardening

Plant seeds or transplants. Application of fertilizer is important at this time because the nitrogen you added in Step 1 took care of only the 2-inch organic layer. Additional nutrients are needed for adequate nourishment of garden plants.

As you read this, you may be thinking, geez, they need a LOT to eat! And it may be starting to dawn on you why our soils are sooo depleted. Read more about that here.

Whether you use organic or manufactured fertilizer, keep in mind that vegetables need a lot of nutrients. They grow rapidly, producing an entire plant and crop for harvest in only 25 to 100 days. Be sure you apply enough nitrogen, phosphate, and potash to feed the plants properly. Pale green plants craving nitrogen probably will appear more often in raised beds than in conventional gardens. Add the nitrogen as needed during the growing season.

Irrigate properly to keep plants growing. The mixture of soil and organic matter in raised beds dries faster than clay soil. On the other hand, the soil is loose, so it absorbs water faster. Soaker hoses or upside-down sprinkler hoses can be used to good advantage. With low pressure, they water only the raised bed.

Keep the walkways as dry as possible to help control weeds. You can place stakes at the corners of the beds to catch the hose and prevent it from damaging plants.

Maintaining Raised Beds

Organic matter decomposes and disappears, so add more of it constantly. Use compost to provide nutrients during the summer. Cover the beds with 2 inches of leaves or other organic material each winter. This material will be pretty well decomposed by spring, and planting can proceed on schedule.

Fill the walkways with leaves when they are available. This will create a trench of composted material that
you can rake up onto the beds later. Think of it as easy schmeezy compost!

Once the beds have gone through the improvement process, rototilling should be unnecessary. Conditions may not be ideal yet in the first spring following bed construction, but light spading or forking will create a suitable seedbed.

As you keep adding more loosening material, you will be able to garden almost all year. Earlier planting will be possible because the improved drainage creates a better environment for plants. It also promotes faster warming of the soil and more rapid growth in the early season. At the end of the season, better drainage means healthier plants that will continue yielding longer. The walkways can provide better footing after rains begin. You are more likely to harvest cool-season crops with less mud to battle!

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