Gardeners react no differently than anyone else when times are tough: They tighten spending and try to squeeze more from their budgets. Some turn to close cropping -- crowding plants as a cheap and easy way to maximize yields from minimal space.
Placing garden plants shoulder-to-shoulder is not a new idea. American Indians are credited with introducing the "Three Sisters" concept, in which corn, beans and squash were planted alongside one another. The nitrogen-rich climbing beans used the corn stalks for structure, while the ground-hugging squash smothered weeds and reduced soil evaporation. The result: three interdependent and eminently edible crops produced from the same ground.
If done right, massing plants in their growing beds is also an efficient way for urban gardeners to make the most of patios or decks, balconies or fire escapes.
"Many gardeners find themselves in a situation of wanting to grow either more produce in the same amount of space or grow similar amounts in a reduced area," said Ben Sturtevant, a marketing specialist with Johnny's Selected Seeds in Winslow, Maine. "This leads to finding ways to change methods or use new methods of production."
Traditional single-row spacing varies, but smaller crops like radishes, leaf lettuces and beets usually are assigned about a foot between the rows, Sturtevant said.
Larger plants, including beans, cabbage and broccoli, generally are given 2 to 3 feet.
Garden beds can be compressed, however, if managed properly. That includes letting enough air flow around the plants to prevent mildew, Sturtevant said.
It also means using rich soil, said Derek Fell, author of more than 100 garden publications. "If you have a lot of nutrition in the soil, then a lot of plants won't mind being crowded," he said.
Rather than planting in single rows, plant in square or diamond patterns, Fell suggested. "That's used extensively in places like Britain where you have space limitations. You can get an amazing amount of production from tight planting."
Here are some space-saving variations:
Grow vertical. "Cucumbers, some squashes, melons and tomatoes can be trellised very nicely," Sturtevant said.
Succession planting. Get a new crop into the ground as soon as the cool-season crop has been harvested. Replace lettuce, radishes and peas with something like beans, beets and turnips.
Inter-planting. Grow vegetables having different maturity dates side by side. A typical pairing might be radishes, which are fast maturing, with carrots, which take longer to mature. Space also can be gained by planting a massed row of leaf lettuce between two rows of tomatoes. The lettuce can be eaten before the tomatoes grow tall enough to shade them out.
Use containers, "a sure way to grow in a limited amount of space," Sturtevant said. "Specific [plant] varieties are now being developed for this specialized environment."
Select "bush" or dwarf plants, which don't take as much space or compete as vigorously for soil ingredients.
"Shop around for 'kit gardens,' or comparable plant varieties that are made into salads, pizza fixings or herbal teas and seasonings," said Linda Chalker-Scott, an urban horticulturist with Washington State University's Puyallup Research and Extension Center. "They're also a neat way to introduce gardening to the entire family, especially children."
For more about maximizing yields from minimal space, see this Iowa State University website: www.extension.iastate.edu/publications/pm870a.pdf