The gardens: four small-space garden types compared

Comparison table

Raised beds

The University of Delaware Cooperative Extension lists the benefits: roots grow above waterlogged, contaminated or compacted ground; soil warms earlier in spring and covers can extend the season; intensive planting can increase yield; and the height reduces bending. Its recommended size is 4 feet wide and 4 or 8 feet long, at least a foot deep, with paths of at least 4 feet between beds. Cedar, cypress, recycled lumber, cinder blocks and bricks are suggested materials; recycled tires and lumber treated with creosote or pentachlorophenol should not be used. Size the fill with the soil calculator.

Containers

Containers put food on any surface with sun. University of Maryland Extension gives minimum sizes by crop class and notes that reused objects, from five-gallon buckets to half whiskey barrels and wading pools, work if they drain. UW–Madison Extension asks for at least six hours of direct sun, commercial potting mix, and daily watering once plants are large. The container size table lists minimums for 25 crops, and the balcony gardening guide covers sun hours, weight, wind and lease rules for containers off the ground. NC State Extension notes that miniature fairy gardens can be made in the ground or in containers and are a way to involve children; see miniature and dollhouse gardens with kids.

In-ground beds

Planting directly in the ground needs the fewest materials and suits crops that sprawl. Its success depends on the native soil; the raised-bed advantages Delaware lists (drainage, warm soil, escaping contamination) are exactly the things an in-ground bed does not provide automatically. Many market growers start in the ground at small scale; ATTRA notes that "many successful growers begin with less than an acre".

Vertical gardens

Virginia Cooperative Extension's guide to trellises, stakes and cages lists pole beans, peas, cucumbers, melons and tomatoes as climbing or trailing crops worth growing upward, and suggests cages for heavy crops such as melons and squash that can overload a trellis. Benefits include efficient use of space, easier harvest, cleaner fruit and better air movement through foliage. Radishes, turnips and lettuce can grow beneath taller vertical crops. Post depths, stake and cage sizes and a crop-by-crop support list are in the vertical gardening guide.

Combining them

The four forms combine easily. One possible layout pairs one or two raised beds planted on a square-foot grid with containers for herbs and tomatoes on a patio, and a trellis on the north edge of a bed for cucumbers or peas. Timing for all of them comes from the same frost dates: see the planting calendar.