Use a greenhouse to grow various types of plants including ornamental, vegetable and fruit plants. Plants can be grown year-round, and growing edible plants in a greenhouse is a way to cut down on the food bill. Greenhouses can also be used to overwinter delicate bulbs and tender perennials that will be replanted outdoors in the spring.
Ornamentals include flowering shrubs, annuals, perennials, biennials and bulbs. When deciding which ornamental plants to grow, consider the size of the greenhouse. Certain shrubs and climbers can grow very large, which is a consideration when space is limited. If space is an issue, Johnathan Edwards, in his book, "Greenhouse Gardening," recommends only growing plants that are difficult to find or expensive to purchase, such as dahlias, begonias, pansies and violas. If space is not an issue, plant flowers and bulbs such as carnations, impatiens, fuchsia, begonia, primula, cineraria, pelargonium and varieties of chrysanthemum for year-round cuttings for fresh flower arrangements.
Use a greenhouse to start half-hardy annuals and perennials in late winter to get a jump on the outdoor growing season and for later transplant into a garden.
Lettuce, onion, okra, carrots, herbs, potatoes and broccoli are just some of the vegetables that can be grown in a greenhouse. The temperature in a greenhouse can be controlled, allowing year-round harvesting. Greenhouses are particularly useful for growing vegetables that are unpredictable outside, such as tomatoes and capsicums, according to, "The Greenhouse Expert," by Dr. D.G. Hessayon. Use greenhouses to sow seeds of plants such as potatoes and peanuts, which have long growing periods, transplanting the seeds into the garden when the ground warms up. Use a greenhouse to start seeds, such as beans, in trays for later transplant outdoors.
Different types of fruit can be grown in a greenhouse, including dwarf fruit trees or bushes such as cherry, citrus and nectarine. Fruit trees require a fair amount of space to grow. Planting them in pots will make them easy to move when space becomes an issue, according to "The Complete Book of the Greenhouse," by Ian G. Walls. Or plant fruit trees and shrubs in pots and transplant the trees outside when the weather cooperates.
Grow grapes in greenhouses. Grape vines are typically planted with wire running over the plants from one post to another post, which the plant will twist itself around for support as it grows. As the grapevines continue to grow, one or two more wires should be added to the posts to encourage the vines to branch out. Grapevines can be pruned to maintain growth.
Low-growing fruit such as strawberries and blueberries can be grown in greenhouses safe from predatory birds and squirrels, which can pick plants clean. Melons can also be grown in greenhouses, and although they require an ample amount of floor space for the vines to grow, pruning can control plants.