For young children and the young at heart living in a small space, I think Square Foot Gardening is the answer!
Square Foot Gardening is the practice of planning small but intensively planted gardens. The phrase "square foot gardening" was popularized by Mel Bartholomew in a 1981 Rodale Press book and subsequent PBS television series. The practice combines concepts from other organic gardening methods, including a strong focus on compost, closely planted raised beds and biointensive attention to a small, clearly defined area. Proponents claim that the method is particularly well-suited for areas with poor soil, beginning gardeners or as adaptive recreation for those with disabilities.
The original square-foot-gardening method used an open-bottomed box to contain a finite amount of soil, which was divided with a grid into sections. To encourage variety of different crops over time, each square would be planted with a different kind of plant, the number of plants per square depending on an individual plant's size. A single tomato plant might take a full square, as might herbs such as oregano, basil or mint, while most strawberry plants could be planted four per square, with up to sixteen radishes per square. Tall or climbing plants such as maize or pole beans might be planted in a northern row (south in the southern hemisphere) so as not to shade other plants, and supported with lattice or netting.The logic behind using smaller beds is that they are easily adapted, and the gardener can easily reach the entire area, without stepping on and compacting the soil. In the second edition, Bartholomew suggests using a "weed barrier" beneath the box, and filling it completely with "Mel's mix," a combination by volume of one third of decayed Sphagnum "peat moss", one-third expanded vermiculite and one-third blended compost. For accessibility, raised boxes may have bottoms to sit like tables at a convenient height, with approximately 6" (15cm) of manufactured soil per square foot.
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