You may visualize your garden under glass as a profusion of bloom and a riot of color, but you will certainly be missing something if you do not include some of the interesting and decorative trailing, climbing, and vining plants. Their distinctive leaf patterns, unusual forms and growth habits, and (on some) magnificent flowers, provide the frame that completes the picture made by your winter garden. They add grace and decoration to the interior of your greenhouse.
Many lovely plants whose nature it is to trail or hang, or even sprawl, are cultivated and displayed to advantage only when they are grown in a container that is suspended, as a basket or pot that hangs from above, or a pot placed on a high shelf.
To some plants nature has given the irrepressible urge and need to climb, clamber, or twine and twist. These plants can be grown in pots or other stable containers placed so the plants will grow up the inside of the glass, thereby shading tender plants on benches; or they can climb on a trellis, wire-mesh, or lattice arrangement of twine, against the solid wall of a lean-to greenhouse or even as floral "walls" to divide sections of benches.
Catalogues available from nurserymen list a variety of types and styles of containers for trailing plants: open-work wire baskets, metal baskets, plastic lattice-type baskets, pots with attached saucers, even ceramic containers or baskets of Mexican fern wood or redwood. I prefer the open-work wire basket for my own plantings; they seem to be more decorative when lined with sphagnum moss and the bits and pieces of moss wander through the openings. No matter what container you select, basic preparation is the same and quite simple.
Line the basket with moss (either coarse sphagnum or sheet moss) that has been soaked thoroughly and pressed firmly to remove excess water. This lining holds the soil mixture in the basket and helps retain moisture in the soil. Next, fill the basket to within about 1 inch of the top with a soil mixture consisting of equal parts of clean sharp sand, well-rotted manure, and garden loam, leafmold, or peatmoss. Water well and let drain before planting.
Care must be taken in the selection of the material to be planted in a basket. Plants mature rapidly under the ideal controlled conditions of ventilation, heat, and humidity provided under glass, and what seems to be a sparse planting when baskets are being prepared will, in short order, fill them to overflowing. In small baskets, plant no more than three evenly spaced plants to a basket. In large baskets, four or five plants can be accommodated depending upon your choice of plant material. Think of the basket as a square place one plant in each corner and one in the center.
Water thoroughly, using a fine spray to help prevent loss of moisture in the leaves due to transplanting, and to settle the plant into the soil mixture. Do not allow soil and moss to dry out or growth will be checked, and baskets will be a disappointment. It will be difficult for you to know the moisture condition of the soil, as the plants will be above eye level, so apply water liberally. Moss provides adequate drainage to prevent water-logging of soil. Liberal watering, however, leaches nutrients from the soil, so a regular feeding program with liquid fertilizer every two weeks is necessary.
For an interesting variety of foliage, color of bloom, and growth characteristics, try various combinations of the trailing and climbing plants listed below. Most of these are for a cool house with a temperature range of 45 to 50 F, but you will find that warmer temperatures near the roof of the greenhouse make it possible to include a few requiring a more moderate climate.
Some of the best are: begonias (tuberous hanging kinds), bougain-villea, browallia, Campanula isophylla, ceropegia, chlorophytum, clero-dendrum, episcia, fuchsia, Hedera Helix (English ivy), hoya (wax-plant), lantana, manettia (firecracker-vine), oxalis, passiflora (passionflower), pelargonium (ivy-leaved geranium), Plumbago capensis (leadwort), Saxifraga sarmentosa (strawberry-begonia), streptosolen (orange-browallia), Trachelospermum jasminoides (star-jasmine), and tradescantia (inch-plant).