Previous: Prefab Plastic Houses One typical, small, prefabricated, plastic greenhouse comes packed in a do-it-yourself kit. The 6- by 8- by 7-foot model sells for under $80.00. Extra 4-foot sections are available so you can extend the house as much as you wish. The manufacturer claims it will stand up under 50-degree-below-zero weather. He recommends for it a $15.00 electric heater.

Running Your Green House Economically The temperature you maintain in your greenhouse plays an important part in plant growth. Greenhouses are classified as cold houses (unheated), cool houses (55 to 60 degrees at night), or warm houses (60 to 70 degrees at night). Whenever night temperatures are cited you should figure on a daytime requirement about 10 degrees higher. Each of these three classes of greenhouses is suitable for growing certain kinds of saleable plants.

If you live where outdoor night temperatures never dip below 32 degrees, you can run a cold (unheated) greenhouse the year round. Otherwise, you might find it profitable to operate a cold greenhouse until late fall, close it down during the coldest winter months, then resume operations in early spring. In such a house, you can make money on annuals, spring-flowering bulbs, and bedding plants by forcing or starting them in late February or early March. The cold greenhouse is also an excellent place for growing lettuce. In summer, use the unheated greenhouse for tomatoes, seedling perennials, or almost any plant that flowers in summer. In this type of greenhouse, winter-grown plants should be planted directly into the bench soil. Here they will withstand lower temperatures than if planted in pots. In the following lists are plants I have found profitable to grow under the various conditions specified . FLOWERING PLANTS FOR THE UNHEATED GREENHOUSE Spring Anemone* Larkspur Astilbe Lily-of-the-Valley Carnation Narcissus* Columbine Pansies Crocus* Primrose Cyclamen* Saxifraga Daffodil* Scilla* Forget-me-not Sedum (Myosotis) Tulip* Fritillaria* Viola Hyacinth* Violet Iris* Summer Begonia (Tuberous and Campanula semperflorens) Canna* Browallia Carnation Calceolaria Celosia (* Denotes plant usually grown from a bulb, corm, or tuber.) Chrysanthemum Hibiscus Crinum* Lobelia Delphinium Oxalis * Dutchman's Pipe Petunia (Aristolochia) Sedum Flowering Tobacco Sweet Peas (Nicotiana) Tigr idia * Geranium Vallota* (Pelargonium) Watsonia * Autumn Carnation Nerine* Chrysanthemum Sternbergia* Gladiolus* Sedum Hosta* Sempervivum Kniphofia* Zephryanthes Lily* Winter Anemone* Iris alata9 Crocus* Jasmine Cyclamen neapolitanum* Saxifraga Erica Solanum Fatsia Viburnum Freesia* Violets

THE COOL GREENHOUSE In the cool house the night temperature in winter should be about 55 to 60 degrees with the usual rise of 10 degrees during the day. In this temperature range, you can grow a variety of plants including all of those suggested for the unheated green house, as well as the plants in the following list, and your heating costs will be far less than those in a warm house of the same size. FLOWERING PLANTS FOR THE COOL HOUSE (Winter night temperature: 55-60 degrees.)

Spring Aquilegia (Columbine) Azalea Browallia

Camellia Carnation Cineraria Clematis

THE PRACTICAL GREENHOUSE FOR YOU Clivia* Lachenalia* Convallaria Lilium* (Lily-of-the-V'alley) * Nasturtium Freesia a (Tropaeolum) Geranium Rhododendron (Pelargonium) Summer

Achimenes* Clematis Agapanthus* Morning Glory Asarina (Convolvulus) (Maurandia) Cup-and-Saucer Vine Begonia (Cobea scandens) (all types) Crinum * Bougainvillea Datura Cacti Fuchsia (Some varieties) Habranthus0 Caladium* Hoya Calceolaria Hydrangea Campanula Impatiens Canna* Lantana Carnation Autumn Bignonia Mignonette Browallia Nerine* Chrysanthemum Salvia Fatsia Streptocarpus Flowering Maple Vallota* (Abutilon) Winter Begonia Chrysanthemum (Fibrous-rooted) Cineraria Bouvardia Cyclamen* Carnation Stocks Christmas Rose (Helleborus Niger) THE WARM HOUSE The actual temperature range of a warm house is 60 to 70 degrees during winter nights. However, most of those who grow African violets, gloxinias, and so forth, as well as foliage plants of tropical origin and nature, find they get more rapid leaf growth and plant increase when the night temperature is 2 to 5 degrees higher than that range. The warm house is also used for growing many of the "stove" plants described in old garden encyclopedias and English gardening books.

(Winter night temperatures: 60-70 degrees.) Spring Acacia Bromeliads Aeschynanthus (various species) (Trichosporum) Calceolaria Amaryllis* Camellia Arum* Carnation Azalea Cineraria Begonias Epiphyllum (Tuberous,* semperflorens, Episcia some rex) Freesia*

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