In choosing the kinds of plants for the main grounds the gardener should carefully distinguish two categories, -- those plants to compose the structural masses and design of the place, and those that are to be used for mere ornament. The chief merits to be sought in the former are good foliage, pleasing form and habit, shades of green, and color of winter twigs. The merits of the latter lie chiefly in flowers or colored foliage.

Each of these categories should be again divided. Of plants for the main design, there might be discussion of trees for a windbreak, of trees for shade; of shrubs for screens or heavy plantings, for the lighter side plantings, and for incidental masses about the buildings or on the lawn; and perhaps also of vines for porches and arbors, of evergreens, of hedges, and of the heavier herbaceous masses.

Plants used for mere embellishment or ornamentation may be ranged again into categories for permanent herbaceous borders, for display beds, ribbon edgings, annuals for temporary effects, foliage beds, plants for adding color and emphasis to the shrubbery masses, plants desired to be grown as single specimens or as curiosities, and plants for porch-boxes and window-gardens.

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