Green House Farming has continued to grow popularity in Kenya due to the fact that many people have turned to farming as a way of making money. The unforeseen changes in the weather has had an effect on crops productivity in the past, however, with the introduction of green house farming the future seems to be promising.
Greenhouse Technology is the technique of providing favorable environment condition to the plants. It is rather used to protect the plants from the adverse climatic conditions such as wind, cold, precipitation, excessive radiation, extreme temperature, insects and diseases. It also of vital importance in creating an ideal micro climate around the plants.
Greenhouses or glass houses provide environmental conditions that are modified to an extent that one can grow any plant in any place at any time by providing suitable environmental conditions with minimum labor.
Advantages of modern green house
- One of the main advantages to growing plants in a greenhouse is that it offers you a longer growing season.
- Temperatures don’t vary as much within a greenhouse, since the sun’s radiation is trapped in the enclosure, retaining the heat within the structure.
- Growing seasons can be extended, even in cold climate
- You have the ability to grow a wide variety of plants when using a greenhouse. It allows individuals to enjoy experimenting with exotic plants that are not found in the local area
- It’s possible to grow plants without all those dangerous, toxic pesticides when growing in a greenhouse. Gardeners can control what they use when growing their own produce.
- When using a greenhouse, it’s possible to conserve energy sources like water, since these energy sources can more easily be controlled as opposed to traditional gardening
What type of greenhouse you need depends on where you live and what you want to grow. Greenhouses are categorized in a variety of ways.
Temperature – The spectrum of structures based on the environmental temperature needs include the following types:
Cold Houses – (Temperature: Falls below freezing) Provide protection for plants, but temperatures still can get below freezing because this type of greenhouse has no additional heat source installed. The purpose of cold houses is to extend growing season in the cold season by allowing crops to mature earlier.
Cool Houses – (Temperature: 7-10°C) This type of greenhouse will maintain temperatures above freezing so that plants that die from extreme cold can survive.
Warm Houses – (Temperature: 12.778°C) Allows for a broader range of plants to survive cold winters.
Hot Houses – (Temperature: above 15.556°C) Hot greenhouses are used to maintain tropical plants. In order to heat they require supplemental heat.
Within each of these general types, there are many other considerations. There are very simple greenhouses and highly complex ones. The more technology that is involved the greater the ability to exactly control the growing conditions, from temperature to water and moisture levels. Greenhouses can also be constructed simply to minimize direct sunlight (a shade greenhouse) and not have walls, or a screen-only structure to keep out insects.
Greenhouses can also be evaluated based on the design style. Some of the traditional types of greenhouse “architecture” include A-Frame, Dome, Arched, Lean-To (can even be designed to use the wall of a home or garage as one side), and Quonset.
Materials – For the residential gardener, the choices are almost unlimited. Price will likely drive some of the decision making on this, as will aesthetic considerations and your purpose. All have advantages and disadvantages.
Support or Framework Options: wood (rots easily), aluminum, iron and plastic. Some have curved eaves; others have flat eaves.
Eaves being the edges of the roof.
Covering Options: glass (most expensive but lasts longest, also beautiful), fiberglass (can become discolored), plastic (cheap but effective), double-layered polyethylene (must replace every 2-3 years), PVC, acrylic (very expensive).
Environmental Control Options – Budget will impact what a farmer are able to do in this area. Automatic controls are ideal in a greenhouse, but obviously will be more expensive. A farmer’s options for heating equipment include a simple space heater, forced-air heat, radiant heat, steam or hot-water systems, as well as soil heating pipes underneath plants. Automatic watering systems for larger greenhouses are nice. Planning for ventilation is also essential for the health of your plants.
The workings of a Greenhouse
When it comes to greenhouse farming this is what a farmer needs to know on how it works:
- In order to provide light, greenhouses need to have some way for the light to come in. This is why greenhouses are made of mostly translucent materials, like glass or clear plastic. This gives the plants inside maximum access to sunlight
- The darker the surface, the more energy it can absorb and turn into heat. This is why black pavement gets really hot in the summer. It absorbs a lot of heat.
- All this light and warm temperatures give plants ample access to the sunlight and temperatures needed to grow. This is because they have the right conditions for photosynthesis to occur.
- Adding a brick floor to your greenhouse means that it will take longer for the building to heat up during the day, but during the night, all that extra heat energy will slowly be released into the air inside the greenhouse. This will keep your plants warm and toasty even after the sun goes down.
- All greenhouses must include vents, either a top vent that opens a hatch in the ceiling or side vents and fans that whisk out hot air and usher in cooler air.