Square Foot Gardening: Growing More In Less Space
By Eric Vinje, Planet Natural
Intensive or square foot gardening uses space more efficiently than traditional methods. Instead of wasted room between rows of crops, the garden area is maximized — that way you get the most vegetables, fruits and flowers in the smallest amount of growing space.
Even if you have plenty of room in your backyard, intensive gardening can require less work while still providing lots of heathy plants. Usually there is less weeding involved since plants are spaced closer together and every bit of garden space is cultivated throughout the entire growing season. However, because there is less room between crops, weeding will need to be done by hand or with smaller garden tools — there will not be enough room for machinery. Another drawback — to some people — is that because plants are always growing, they are not all ready to harvest at the same time.
A raised bed is simply when the level of the soil is higher than the surrounding ground. The Ohio State University Extension has listed several benefits of gardening in a raised bed. A few of these benefits are:
• Higher yields
• Improved soil conditions
• Ease of working
• Ease of pest control
• Water conservation
A raised bed should be just wide enough that you can reach all the way across without climbing into it (or, if you can access both sides of the bed, you need to be able to reach half way across). See Building a Raised Bed Garden (PDF format).
One of the reasons raised beds have such high yields is that the soil is mixed with humus or compost to create a light, fluffy growing medium to a depth of about 2-feet. This encourages great root growth.
Vertical gardens are both a wise use of space and aesthetically pleasing. Plants grown on walls, trellises and fences can cool your home or garden and block views you don’t want to see.
Good support surfaces for a vertical garden include:
• Openwork fences
• Hanging baskets
• Poles with string or nets
Choosing the right plants for a vertical garden is important. While many plants can be trained to grow upwards, not every plant is suitable. Some of the best fruits and vegetables are as follows:
Tomatoes do better grown in a cage or other support system than when left on the ground. Not only do they use up less space, but they are less likely to become infected with a soil-borne disease. Learn more about tomato gardening here.
Cucumbers grow as vines and are a natural for vertical gardening.
Corn grows vertically, naturally, and can be used as a support for beans or other plants.
Peas, melons, and passion fruit take well to upwards growth. Even zucchinis, pumpkins and other squashes will grow vertically as long as their support system is strong enough.
Tips for a Successful Vertical Garden
1.) Make sure your vertically-grown plants are in a location where they won’t shade out sun-loving plants.
2.) Grow plants on the south side of the support structure for maximum sunlight.
3.) Don’t forget to water. Your vertical garden will dry out faster without plants laying on the soil to shade it.
4.) Soil should be deep and well-drained so plant roots can grow down into the soil, rather than growing outwards where they will compete with other plants.
5.) Heavy crops, such as melons, pumpkins and squash, may need additional support. Construct a “hammock” from strips of old pantyhose by tying it to either side of the crop you are supporting and place the vegetable/fruit inside.
Growing two or more plants in the same place at the same time is known as interplanting. This can be done by alternating rows within a bed, alternating plants within a row or mixing up plants throughout the bed.
When interplanting flowers and herbs in the vegetable garden make sure to grow plants with similar requirements near each other. Consider the following factors for each plant:
• length of the plant’s growth period
• growth pattern (tall, short, below or above ground)
• possible negative effects on other plants (such as the allelopathic effects of sunflowers and Jerusalem artichokes on nearby plants)
• preferred season
• preferred light
• nutrient and moisture requirements
In a raised bed or interplanted garden, plants are grown more closely together than in a traditional row garden. When growing vegetables, herbs or fruits, stagger your rows so that a plant in one row is between two plants in the other row. This creates an almost continuous leaf cover that shades out weeds and reduces the amount of area that needs to be mulched.
The following chart from the Arizona Cooperative Extension indicates how closely seeds or seedlings can be planted.
|Asparagus||15 to 18||Lettuce, head||10 to 12|
|Beans, lima||4 to 6||Lettuce, leaf||4 to 6|
|Beans, pole||6 to 12||Melons||18 to 24|
|Beans, bush||4 to 6||Mustard||6 to 9|
|Beets||2 to 4||Okra||12 to 18|
|Broccoli||12 to 18||Onion||2 to 4|
|Brussels sprouts||15 to 18||Peas||2 to 4|
|Cabbage||15 to 18||Peppers||12 to 15|
|Cabbage, Chinese||10 to 12||Potatoes||10 to 12|
|Carrots||2 to 3||Pumpkins||24 to 36|
|Cauliflower||15 to 18||Radishes||2 to 3|
|Cucumber||12 to 18||Rutabaga||4 to 6|
|Chard, Swiss||6 to 9||Southern pea||3 to 4|
|Collards||12 to 15||Spinach||4 to 6|
|Endive||15 to 18||Squash, summer||18 to 24|
|Eggplant||18 to 24||Squash, winter||24 to 36|
|Kale||15 to 18||Sweet corn||15 to 18|
|Kohlrabi||6 to 9||Tomatoes||18 to 24|
|Leeks||3 to 6||Turnip||4 to 6|
Note: To determine spacing for interplanting, add the inches for the two crops to be planted together, and divide the sum by 2. For example, if radishes are planted next to beans, add 2 inches + 4 inches = 6 inches, then divide 6 inches by 2 inches = 3 inches. The radishes should be planted 3 inches from the beans.
Tip: Be careful not to sow seeds too closely together or your plants may be at a higher risk of disease (often caused by poor air circulation). Always refer to the seed packet for appropriate spacing.
Succession and Relay Planting
Once a crop has reached its full production, it is time to plant more. Cool-season crops (peas, lettuce, broccoli) are followed by warm-season crops (peppers, tomatoes, beans), and if you live in a mild climate, these may be followed by more cool season plants, or even a fall/winter crop. Learn more about successive planting in the home garden here.
Relaying is overlapping planting of one type of crop. For example, spinach may be planted at 2-3 week intervals to ensure a steady harvest. Or you can plant early, mid and late season crops all at the same time (see Planting Crops for a Second Harvest).
If seeds are started indoors, there is always something ready to go into the garden as space opens up. Don’t forget to add compost or an organic fertilizer to get the soil ready for the next crop of plants.
Planning & Design
Start early when planning an organic garden. In January or February, while snow still covers the ground, it is time to get out some graph paper and seed catalogs and get to work.
1.) Pull out last year’s gardening notebook to see what did and didn’t work in your garden. What? You didn’t keep notes? Learn The Nuts and Bolts of a Gardening Notebook here.
2.) Grab a pencil and paper and draw your garden plot(s). Using graph paper helps determine how much space you have to work with more precisely.
3.) Choose what plants you wish to grow. For each plant consider:
- Nutrient needs
- Shade tolerance
- Above- and below-ground growth patterns
- Preferred growing season
4.) Determine which plants can be grown together or successionally. Read more about companion planting here.
5.) Add the plants to your chart after determining how closely together they can be grown.
6.) Order your seeds. You can start some plants indoors so they are ready to go or directly seed into the soil.