Evergreens and Berried Branches for Winter
Winters need not be dull. After annual plants are lifted, evergreen branches can be inserted in the soil. These will last until spring, when it is time to set out the first pansies. Branches of balsam fir, white pine, red, Scotch, or black pines, and Douglas fir stay green all winter. Spruce and hemlock will shed their needles when it gets too warm, but replacements can be made. In warm areas such broad-leaved evergreens as podocarpus, pit-tosporum, leucothoe, mahonia, and bull-bay magnolia last several weeks and can be replaced from the abundant supply in the garden.
Berries can be added to the greens. Bittersweet is one of the best, but red alder also stays plump and fresh outdoors. Always colorful are California pepper berries, nan-dina, sea buckthorn, and love apples. Cones and gilded or silvered seedpods and branches are festive at Christmas, with artificial berries and fruits as other possibilities. Where squirrels are not a problem, window boxes can also be turned into feeding stations for winter birds.
Of course, window boxes can be directly planted with small evergreens, needled or broad-leaved. Dwarf Japanese yews are excellent, but small junipers and spruces, bear-berry, leucothoe, leiophyllum, pieris, pachistima, rounded arborvitae and boxwood, where not subject to winter injury, are also candidates. In spring, these evergreens can be planted in the garden and room left again for summer-flowering plants. Or you might have two sets of boxes, one for summer and one to set along the terrace perhaps and bring back for winter.
Large window boxes on firm foundations can be partially planted with small evergreens for year-round green, with geraniums, petunias and other flowering plants added for summer color. In this case, boxes must be large enough to accommodate both groups of plants. Such boxes, often made of concrete, adorn hotels, department stores, restaurants, and business offices as permanent features at windows and doorways.
If you plan to grow evergreens in your window boxes in winter, remember that the plants will need water. In warm sections, where camellias, pittosporum, podocarpus, osmanthus, dwarf hollies, nandina and others are hardy, the soil does not often freeze solidly. Despite cold weather,
watering, though less frequent than in summer, is needed. In the rush of the holiday season, this chore is too often overlooked.
When Soil Freezes
In the North, where soil freezes it cannot be regularly watered. Meanwhile plants are constantly evaporating moisture that they are unable to replace. This causes windburning and sunscald. It can be somewhat mitigated by heavy watering whenever there is a slight thaw. These will give roots sufficient moisture for another period of freeze. Gardeners often think that plants in containers do not require watering in winter. This explains why evergreens in window boxes, tubs, and planters are unsightly or dead by spring.