Broccoli can be a prime raised bed crop, here growing in 20-inch-wide raised beds.

Over the past several years at the Noble Foundation Horticulture Center, experiments have been conducted with various bed widths. Crops were successfully grown in 6-foot-, 5-foot-, 4-foot-, 3 1/2-foot-, 3-foot- and 20-inch-wide beds. Every width has advantages and disadvantages.

Each gardener should consider several factors before deciding on a bed width. Some of these include:

Value. As bed width increases, construction cost per square foot decreases. A 5-foot by 20-foot bed constructed of 2-inch by 12-inch lumber is comparable in cost to a 3-foot by 20-foot bed of similar construction (approximately $100, not including labor or soil medium costs). The material cost per square foot is considerably less for the 100-square-foot bed ($1 per square foot) compared to the 60-square-foot bed ($1.66 per square foot).

Utilization of space. Another advantage of wide beds is increased utilization of space. Generally speaking, the wider the beds, the fewer the pathways. Where space is limited, more bed space and fewer paths translate into more yield per square foot of overall garden area.

Climate control devices. Many plastic row covers and mulches are available for use on 40-inch or narrower beds. Also, the narrower the bed, the easier it is to apply these devices. With wide beds, some of these materials must be custom made.

Personal stature. Tall individuals can easily reach the center of a 5-foot bed. Most people find it more convenient to use narrower beds. On wide beds, it is often necessary to place one foot on the bed and the other on the path, in order to reach the center. Stepping on beds is not encouraged because it compacts the soil. However, this practice is easier on the gardener because it takes strain off the back. This may sound trivial, but to anyone with a bad back, placing a foot on the bed makes all the difference in the world. No detrimental effect on yield has been noted from occasionally stepping on beds, especially when a large growing area is utilized. Anyone not wanting to step on beds can place a 1-inch by 12-inch standing board across the bed top. This will reduce the possibility of soil compaction.