When I plant my vegetable garden, I follow a modified version of what is often called Intensive Spacing. Square Foot Gardening is one example of a garden method that relies on intensive garden spacing. It does not use farm-style rows; instead, plants are set into the garden in a grid-pattern, and they often are placed very near to each other. (Note: The Square Foot Garden book has helped a lot of new-gardeners find success in growing food, and in many ways it is pretty awesome.)
My version is modified in that the spacing I use is a bit roomier than in some of the grid-style intensive planting schemes I have seen. There is more than one reason for my spacing plants a bit farther apart than is sometimes recommended.
The intensive planting guide that I started out with, John Jeavons’ How to Grow More Vegetables , suggests starting bush beans at a 6-inch spacing, and that is what I tend to use, but for big varieties like ‘Provider’ bush beans I make the spacing bigger. The Square Foot Gardening book I read (early edition, so it may be changed now) suggests a shorter distance – fitting as many as 9 bean plants into a square foot of garden. My version fits 4 (or fewer) plants into one square foot of space.
The theory supporting tighter spacing is that even though there may be fewer beans per plant, the overall productivity of the square foot of space will be higher. That makes total sense.
However, when the tops grow to maturity and are making beans galore, the dense tangle of leaves and stems make the beans hard to find. For me, the convenience vs. exasperation factor is a consideration.
This tangle of growth can be a problem for more plants than just the bush beans. Following the suggested spacing for many crops in intensive planting systems can result in a mess.
The second reason for wider spacing is related to drought and the time required to water a garden. When plants are spaced more closely together, their roots cross into each others’ soil-space. The roots of several plants will all be pulling nutrients and water from the same chunk of soil.
In a drought, in hot weather, a mature garden with big plants will need a lot of water. If those plants are very close together, all trying to get moisture from the same little bit of soil, they may need to be watered every day. Plants in raised bed gardens (which dry out faster than in-ground gardens) may need to be watered twice a day. Do I have time for that? No.
Steven Solomon, whose book Gardening When it Counts: Growing Food in Hard Times, has a tip for growing food in drought conditions. The tip is to make the plant spacing even wider when rain is scarce.
If the original spacing was fairly close, and the rains have stopped indefinitely, he suggests pulling some of the plants out of the garden. The remaining plants will have less competition for water, and the gardener will need to water a little less often.
My sister in Louisiana plants her bush beans 9 inches apart. Since her area is hotter and drier than mine, NW of Atlanta, this spacing makes sense for her garden. She doesn’t have time to water every day, either.
For gardeners who need high productivity and who can get plenty of water out to the garden in a long, hot, dry spell, the closer spacing patterns will be a better choice.
For the rest of us, if our upcoming summer gets as hot and dry as the last one, and if watering the garden becomes a seemingly endless chore, you might consider pulling up a few plants to see if Steve Solomon is right.