The city, with its houses built smack up against the sidewalk, its factories belching out smoke to darken the skies and its tall buildings blotting out the sun, is scarcely a place in which one would expect to find a garden, and for that reason the tiny spots of nature's colors which may be coaxed from the urban earth are as appreciated as they are unexpected.
Revitalizing the soil
Houses in great cities usually back onto small courtyards, divided by brick walls or scrubby plank fences. Looking down into such a yard from a rear window, the city resident is aptly termed a cliffdweller, is invariably thrilled to find fresh greenery and bright blossoms where once a laundry pole reared to a height of five stories or a scraggly ailanthus or gingko tree formerly cast its skinny shadow over sour, hard-packed, acid soil.
In such a garden, coldframes and hotbeds have little use and the gardener needs no knowledge of propagation by budding, layering, cuttings, or grafting. His main problem is preparing a good soil and keeping it that way.
The foundation of most such gardens consists of the soil excavated to build a cellar, mixed with old plaster and any other sort of building waste, with no more than a thin skim of topsoil, if that. If it is at all feasible, the best approach to developing a garden in this plot is to dig it out to a depth of 2 or 3 feet and replace it with a mixture of good soil, generously laced with manure, sand, and peat, and dressed well with lime.
The city gardener is warned that this is difficult and expensive but it has been done. One couple spent an entire spring digging out their back yard, filling bags and garbage pails with the old dirt and hauling them to the sidewalk for the city's Sanitation Department to remove.
Most city yards have been built with a drain, usually in the center. Before putting in the prepared soil, the bed should be lined with 3-inch or 4-inch hollow tile, sloping slightly toward the drain, or with 3 or 4 inches of cinders. If there is no drain, these linings will filter the moisture gradually into the soil. At the same time a water line may be prepared. It is not a difficult plumbing operation to bring a pipe extension from the house. A 25-foot garden hose will be sufficient.
If it is not practicable to replace the old soil, it should be well spaded and generously supplied with manure, peat, ground charcoal, and sand. It should be turned over several times to aerate it as much as possible and to expose it to any sunlight that can find its way into the yard.
Bowers in back yards
With no more preparation than this, surprising results have been obtained. A border of ivy forms a permanent ground covering, through which tulips, hyacinths and daffodils push brightly in the spring against a background of rhododendron and azaleas. When the flowers and shrubs have ceased to bloom, a cool green background of the shrubbery foliage remains, beneath a wall covered with lovevine, a persevering climber which will flourish in the worst conditions.
Since a big city garden offers little place for vegetative propagation and transplanting, it is wise to buy plants that are already started. Many of them can be obtained reasonably from the good florist or the garden counters of department stores or five-and-ten-cent stores. The plants they carry usually are the ones which are certain to flourish in the city, because years of complaints from despairing customers have taught them just what plants are foolproof.
Building airy centers
In these small, walled-in, back-yard city gardens it is best to do the planting around the borders of the plot, leaving the center open to admit as much air and light as possible. It is important not to crowd anything in such a garden.
The center may be planted with grass or covered with bricks. or flagstone, planting grass or rock flowers between the stones. Bricks and flagstone can be purchased from a building supply firm, or from seedsmen, and can be laid easily. Dig out to a depth of 8 or 10 inches the earth which they will cover. Level off the bottom of the bed and pack it well. Cover it with 4 inches of cinders, and shovel in a 1-inch blanket of sand and soil. Then set the flagstones, which should run from 1 to 3 inches in thickness. Place a board across them to show that their rise is even, and slant them slightly toward the drain. Fill the spaces between the stones with soil, peat moss, and sand.
Importance of lime
As most big city back yards are sour and acid, the application of lime to the soil is important. The soil first may be tested by a simple method. Take several samples from various parts of the yard, mix them thoroughly, and dry them out. Put the earth samples in a jar and pour over it a small amount of muriatic acid, readily available from a drug store. If the soil fizzes vigorously, the lime content is ample. If the fizz is moderate, a moderate application of lime is indicated. If there is no reaction, the soil is highly acid and requires a generous quantity of lime.
This should be applied in the fall, in the form of slaked lime; it will help to control pests and disinfect and hasten the decay of manure as well as neutralize the soil. Two to three pounds of lime per square yard is the usual application.
Mulch is as important to a cramped backyard garden as to the beds in a broad and airy lawn. Since a compost pile is hardly feasible and fallen leaves are scarce, the city gardener will help his soil by light cultivation. For his use a mulch of peat moss is recommended. It is clean and easy to handle.
The garden should be watered carefully. The beds should be soaked well and evenly, and allowed to dry before watering again. Spraying the foliage with water early in the day will help to get rid of dust and dirt.
Some houses in large cities lack even a grubby rear yard, backing only onto a rock-filled alley. In such cases the nature-loving dweller may wish to build a roof garden. It is difficult and expensive to get soil to a rooftop, and disposal is difficult. Hence it is advisable to use boxes made of redwood or cypress, or pots and urns of clay or cement. Even a butter tub or a lard bucket will serve.
Plants that succeed
In a garden on a rooftop or in a shaded, airless back yard, the selection of plants is extremely important. Numbers of city gardeners have achieved satisfying results with the following plants: