Growing under cover is the growing of plants in a translucent shelter for plants. It may be done using several types of shelter:
- traditional or DIY cloche; a shelter for one plant
- cold frame: a shelter for a small amount of plants, consisting of a box with translucent lid
- windowsill: the interior sill plate (behind the window) on which plants are placed
- propagator; a metal frame with several planks above each other. The whole is covered with a translucent material (often plastic). They can also be used inside a greenhouse so as to provide double insulation to seedlings. See Plant nursing
- greenhouse: a man-sized structure often consisting of a metal frame and glass as the translucent material
- polytunnel: a tunnel; often man-sized or even less than man-sized (may require crouching to enter) made using PVC or wooden beams and a plastic as the translucent material
- geodesic dome: a dome made from a metal or wooden frame and glass or plastic. Due to the shape, it has no cold/heat pockets, yet the structure is difficult the produce and thus expensive (when bought).
- conservatory: a sort of greenhouse that is made as part of the house (connected hereon). It hence contributes to the heating of the house aswell.
Operation[edit | edit source]
All of the shelters above capture solar energy and use it to create a warm environment for food production.
They can also be used (using an appropriate design) to provide hot water.
Inside the shelter, ponds can be constructed to act as a heat sink and attract frogs; toads, ... to eat pests. Water butts (which may be filled from water from the shelter's roof) also act as heat sinks. Finally, the Strawbridge heat sink (shown on the righ) may also be used for this purpose.
Advantages and disadvantages[edit | edit source]
Translucent shelters, if properly protected with screens and without gaps for pests to enter, can offer advantages in pest control. However, they can also offer favorable conditions for pests to flourish, if pests are allowed to establish themselves.
Waste heat from industry can be used to heat greenhouses: Greenhouse waste heat exchange.
Which plants are grown indoors/outdoors ?[edit | edit source]
Annual herbs such as dill, caraway, basil, borage, chamomile, garden marjoram, chervil, cumin, parsley, anise, coriander, and annual bean herb are sown. This is done in spring from late March, on site, in the soil. Also, frost-sensitive annual herbs such as basil are sown in March-April, under glass. Seeds that germinate slowly (parsley) too are better sown under glass.
The cutting of some plants (e.g. tarragon) is best done in a greenhouse because the cuttings are then in a growth-promoting climate and will dry-out less.
Herbs are not only supplied and used in their natural growing period. The cultivation of herbs can also continue during the winter months. In cold and temperate climates, the cultivation during the winter months is completely done in a greenhouse.
In a mild climate, (e.g. Sydney or Perth in Australia, or the southern United States) many herbs can survive over winter. Some annuals, notably basil, may even be made to survive another year if cut back very hard (removing almost the entire bush) to prevent going to seed. This might need to be performed multiple times, especially removing any buds and flowers than manage to form.
According to the location of cultivation, we can make the following division:
- In full soil
- In container
- In full soil
- In container
- In pot or press pot
- In trays or multi plates
See also[edit | edit source]
- Plant nursing: nursing plants in a greenhouse
- Underground farming: growing under cover yet without using sunlight