My first exposure to vegetable gardening was by my parents. While living in the Delta region of Mississippi, in my early teens, my parents grew a rather large garden. As memory serves me the garden seemed to spontaneously produce vegetables without much effort. The soil was rich and the sun plentiful. I remember working side by side with my dad and enjoying the produce as prepared by my mother. Looking back now, I am sure that garden helped spark my interest in plants.
Today I live in a suburb of Seattle and have a garden of my own. Comprised mostly of raised beds and containers I enjoy the harvest as much as the planting and maintenance. My raised beds are made from 2″ x 10″ untreated boards and are 4′ x 8′ in size. This year with help from my brother we built and installed six more beds. I have chosen to garden in raised beds for a number of reasons. Raised beds can provide higher yields, better soil conditions, less labor and even a better approach to pest control.
Traditional in ground gardening on the home scale level can produce on average 0.5 pounds yield per square foot. Research has shown that raised bed gardening yields on average 1.25 pounds per square foot, more than double the conventional method. Most of my experience in raised bed gardening has proved that research to be accurate.
Plants are planted closer together in the raised bed situation. Elimination of pathways allows for rows to be placed closer together, additionally plants growing closer together will help shade the soil surface and reduce competition of weeds adding to the plants ability to achieve a higher yield. Avoid the temptation to over plant as that will reduce the plants ability to produce a good yield.
Better Soil Conditions
Adding to the higher yields is the overall improvement of soil conditions. Essential to plant development is the ability for air, water and roots have to move through the soil. Compaction of the soil by foot traffic and equipment greatly reduces plant growth and yield. Tilling or digging the soil helps reduce this problem in conventional gardening, but a raised bed gardener can avoid the problem by making the beds narrow enough to work from its edges.
Raised beds enable areas not suited to garden due to topography and soil conditions to produce a yield. As the level of the soil in the bed is raised above the surrounding soil its height allows for positive drainage avoiding saturation. Where there are concerns of soil contamination of the native soil on site, imported soil from a tested source can enable gardening in an area that was not originally suited for such an activity.
Compared to traditional in-ground gardening the soil temperatures in raised beds achieve a warmer temperature earlier in the spring allowing for earlier germination and gardening. To stretch the season further I have added small hoop houses to my garden beds as of this writing the temperature of the soil in my small hoop house raised beds are 7 degrees warmer than the soil in my other raised beds.
Raised bed gardening not only benefits the plants and their yield, advantages extend to those working within the garden. Where mobility of the gardener is concerned, raised beds can be built up so as there is less bending involved in working the beds. Garden beds can also be built to accommodate the gardener that is bound to a wheel chair.
Raised beds can be worked earlier in the spring with out fear of compaction of wet soil as the gardener need not walk on the soil surface to work the beds. The pathways between the beds can be covered with materials that prohibit weed growth and keep the surrounding soil from washing away. I have used straw, chipped tree trimmings and gravel to cover the paths between beds, brick or even stone would add a nice finish to the garden. Making the pathways weed free will allow the gardener to concentrate more on the garden beds.
Deny the Mole
Raised beds can also be a big benefit when dealing with some garden pests. Burrowing animals such as gophers and moles can be denied access to the raised bed by lining the bottom of the bed with wire mesh. The elevation of the raised bed with an added low fence can keep out rabbits. I also find it beneficial that the raised height of the bed puts the plants in the gardeners view better than if they were on the ground, allowing the gardener to spot pest problems sooner.
I have heard many times that the added cost of the building materials, make raised bed gardening prohibitive for many. There are plenty of creative uses of recycled material used for building beds that greatly reduce or even eliminate the need for purchasing products to build the beds. Due to the increased yields a gardener doesn’t need to dedicate as much space to the garden. My recommendation to any new gardener is to start small, plant one bed a year and spread any cost out over time.
While raised bed gardening may not be suited to all gardeners and their methods I find them to be of great benefit to me. For some great inspiration read Jon Jeavons’ “How to Grow More Vegetables and Fruits (and Fruits, Nuts, Berries, Grains, and Other Crops) Than You Ever Thought Possible on Less Land Than You Can Imagine” and Mel Bartholomew’s “All New Square Foot Gardening: Grow More in Less Space!”