The type of raised bed gardening known as Square Foot Gardening is a technique of intensive planting developed in the 1970’s by a retired civil engineer, Mel Bartholomew. It is a simplified version of many of the concepts developed by Alan Chadwick who brought together the Biodynamic and French intensive methods, as well as his own unique approach, to form what he called the Biodynamic-French Intensive method. The method was further developed by John Jeavons and Ecology Action into a sustainable 8-step food-raising method known as "GROW BIOINTENSIVE." The method now enjoys widespread practice and development.
The biointensive method is a whole, interrelated farming system which focuses on maximum yields from the minimum area of land, while simultaneously improving the soil. It’s components must all be used together for the optimum effect.
Square Foot Gardening is a simpler method for home gardeners that is based on a grid of 1-foot by 1-foot squares within a raised bed in your garden. Single seeds or plants are placed in these carefully determined spacings. This system lets you make the most of your garden space to conserve the amount of water, soil conditioners, and labor needed to produce a maximum amount of food in that space. In addition the use of close offset plant spacing allows more plants in an area, thereby increasing the yield. The close spacing of plants shades plants roots, creating a micro-climate under the leaves. This conserves water and blocks out weeds.
A square foot garden takes only one-fifth the space and work of a conventional single-row garden to produce the same harvest.
How to develop a square foot garden.
- Level Ground
- Water Supply
- Adequate light
- Till soil under bed to encourage root growth and soil improvement.
- The beds should be no more than 4’-5’ wide. You want to be able to reach the middle of the bed without stepping on it.
- Any length is fine, however, don’t over estimate the amount of work it takes for larger gardens. You may want to experiment with smaller beds the first year.
- The height of the bed depends on your soil. If the soil is heavy clay then you will want a deeper bed since this method is based on having very deep, high quality soil and good drainage. A higher bed also makes gardening easier since you don’t have to bend down as much.
- Once you have constructed your bed measure off one foot lengths on each side and attach strings from one side to the other to lay out your one foot square grid. Each one of these squares will contain one kind of vegetable or flower.
Soil (most important)
- In order to grow healthy vigorous plants whose roots go down, not out, you need the highest quality soil you can find for the entire depth of the raised bed. This soil should contain both macro and micro nutrients. You should add high quality compost to your soil on a regular basis.
- If you start with clean, fresh soil you can avoid the problem of dormant weed seeds and pests.
- Because you will not be walking on the beds the soil should stay loose, allowing both air and water that the plants need to penetrate to the roots. Soil compaction can reduce crop yields up to 50 percent.
Choosing What to Plant
- Choose vegetables that your family likes to eat!
- Make sure that your garden gets enough light if you want to plant vegetables that bear fruit; tomatoes, squash, eggplant, etc.
- Plants where you eat the leaves can get by on less sunlight; lettuce, chard, etc .
- You may want to surround your garden with plants that attract pollinators; lavendar, rosemary or yarrow.
- If you choose vegetables that can climb make sure that you have a trellis, etc available. You increase yields if your plants are growing up, not along the ground.
- Put climbing plants on the north side of your garden bed or next to vegetables that can take some shade. The north side of a small bed is ideal for climbers since the sun comes from the south.
When to Plant
- Raised beds warm more quickly in spring, so you can work the soil and plant earlier.
- Warm soil, around 80°+, is critical to summer crops. Check your soil with a soil thermometer before you decide to plant.
- Remember in this area you can grow crops year around, cool season crops in the fall and winter, warm season in the summer.
- Cool season vegetables can grow in soils 55° to 70°. You can grow lettuce year around in this area but you will need to shelter it from fall heat spells and winter frosts.