Companies today are actually developing different varieties of vegetables designed to grow well in greenhouses. Many vegetables will grow in a greenhouse but some will grow distinctly well – in fact much better in some cases than they may grow outdoors. The reason for this is that in most cases they are not competing for sunlight with other plants that may be overshadowing them. In addition, they are also not being bothered by birds and insects that can be detrimental to the plant.
Greenhouses offer protection from the frost and cold during the cooler months, as well as from most of the pests that plague the average outdoor garden. The best producing greenhouse vegetables will grow from seeds that have been specifically developed for use in the greenhouse environment. One thing to keep in mind is that in the greenhouse you don’t have the natural pollinators such as insects so you’re going to have to shake your plants slightly and to use a paintbrush or other method to ensure pollination of the flowering type plants.
Nearly every kind of tomato and pepper will grow well in a greenhouse or hothouse. Always remember that space is typically at a premium in a greenhouse so you want to select the kind of tomatoes and peppers which will grow well upright, as opposed to the bushier variety. You can grow tomatoes of the bush type in a greenhouse, but they are going to take up a great deal more space.
Cucumbers grow extremely well inside a greenhouse. They are forgiving of mistakes and are very prolific in growth, producing a large amount of vegetables for the growing space that you use. Remember to prune frequently to get the most from each plant.
Leaf vegetables such as spinach and lettuce grow well inside a greenhouse. They are nearly perfect for this kind of environment and can be grown in the early spring even in an unheated greenhouse so long as the temperature stays above about 45 degrees. This gives you some great options. If you live in a warmer climate you can start your lettuce and spinach growing quite early in the year and be harvesting in the very early springtime.
Root vegetables are something that many people don’t envision when they consider greenhouse growing but many do very well in this environment. Carrots are easy to grow and produce a lot of vegetables in a very small space. They will need to be thinned after they start to grow. Giving them enough root space so far as depth and spacing is imperative but aside from this, because they are beneath the soil they will tolerate cooler temperatures quite well. An unheated greenhouse as well as a heated greenhouse will offer them plenty of warmth for growth. Keep the temperature at about fifty degrees and carrots will produce well so long as they are encased in a more sandy type soil and have plenty of nutrients.
Potatoes can also be grown in the greenhouse. These may be planted in the late winter and will be producing small tender potatoes by mid spring, putting you well ahead of the other gardeners at harvest time. Potatoes need a soil that is richer in nutrients, as well as plenty of growth space for each plant.
If you’re a lover of beets, these too do particularly well in the greenhouse. Giving them plenty of space ensures there will be a harvest of the smaller beets, used for canning or cooking, can take place earlier in the year.
Thinning your plants is an important part of any greenhouse growing, but is very important in the root vegetable department since they require root space to develop to their full potential.
All of your plants should be allowed to grow until they reach full ripeness rather than being picked early. This ensures full flavor and sweetness. Allowing them to remain on the plant or vine is the best way to get peak flavor in greenhouse vegetables.
Marion Catubig is a Garden & Greenhouse contributing editor and the owner of GreenhouseHut.com a company that sells hobby greenhouses and other gardening supplies.