Greenhouse farming is a type of farming where specific plants are grown in an enclosed environment usually a wooden or a metallic structure covered with a radiation sensitive polythene film ( usually EVA or SOLARIG ROOF 172) on the roof for enclosure and CO2 concentration. An insect net usually 90% netting material is used on the sides. This ensures that the air circulation in the greenhouse is good. Within the greenhouse structure, the conditions such as temperature, humidity and radiations are regulated to provide an optimum for the plants growth to maximize yield. it also helps to control pests, diseases and harsh weather.
For well constructed affordable greenhouses, visit our offices in Westlands- Museum hill inside the National Museums of Kenya. You can also call us on +254710399385 or +254737825568 or mail us on sanadreangreenhouses@gmail.com
Kenya, as an agriculturally uprising country has gone milestones in embracing the greenhouse technology. It is true that we are generally in the equatorial climatic region and our temperature, rainfall and humidity are well balanced at levels almost optimum for growth of most plants e.g maize, beans,coffee, sorghum, kale and cassava. This has always made most farmers to avoid greenhouse farming in Kenya and engage in both subsistence and commercial outdoor farming of the above named crops.
The diversion that leads to the increment of greenhouse farming in Kenya and much of Eastern Africa comes in as result of increased demand for exotic crops which are not well endorsed to our equatorial climate. Kenya to be specific, experiences a generally warm and wet climates through out the year with temperatures ranging between 15 to 40 degrees Celsius. This is subject to variation in different regions of the country. This kind of climate does not support plants like,flowers, tomatoes, capsicum, coriander, collards and cucumber perfectly well. This calls for adjustments to be made for them to grow well. For this reason many farmers in Kenya have resolved to greenhouse farming since it offers controlled kind of farming.
Some of the greatest challenges when growing open air plants is weather unpredictability. Lack of rainfall at crucial points in the life of plants will bring losses to farmers. Greenhouses tackle this by using an alternative farming technique known as drip irrigation, this we shall look at as the second technology.40% of the Kenyan regions are generally dry for a good period of the year, this challenges outdoor farming and makes it very difficult. Farmers then opt for greenhouses which are fitted with drip irrigation kits.
Greenhouses improve productivity by making sure that plants are harvested for the entire duration of its maturity rather than just a short time with open air farming. A greenhouse can bring In as much as ksh 400,000 in a season making it a very profitable investment
Another reason for greenhouse farming is the menace of pests and diseases. aphids, white flies, moths, spiders and much more are commonly found in the Kenyan local environments. These insects pose a threat to the plants’ health which result into minimal and low quality yields. To escape this, farmers have resolved to greenhouse farming where the pests are locked out and its easier to control them.
However much greenhouse farming is not as cheap as outdoor farming since it requires a lot of inputs and management skills to get the best outcome, many farmers opt for it because if well done and managed, it can pay well.
Generally a 8m by 15m metallic tunnel greenhouse can cost roughly 200000 Kenya shillings but after the second season, the farmer shall have recovered the construction cost plus some little profit. The seasons thereafter will be pure profit to the farmer.
GREENHOUSE TOMATO FARMING IN KENYA
Kenya’s demand for tomatoes has increased rapidly in the past seven years. this have motivated farmers to engage in tomato production. The price of tomatoes have also gone up, this has fueled the rapid increase of people interested in greenhouse tomato farming in Kenya. Various breeds of tomatoes are produced in various regions of Kenya, the most common one being ANA F1. Other common breeds are; EVA F1, Tylka F1, Bravo, Maxim and Rambo.
Other vegetables that are often grown besides tomatoes are; cucumber, couchette, zucchini, capsicum and kale.
GREENHOUSE COMPANIES IN KENYA- THEIR CONTRIBUTIONS TO GREENHOUSE FARMING IN KENYA.
Various greenhouse companies in Kenya have made great strides in the greenhouse technology since its inception in 1963. The firms have introduced new innovations in agriculture, uplifted the standards of farming in Kenya and helped growers develop markets for their produce.
For instance, In 2009, Amiran Farmers Kit was developed. The kit has grown widely popular around the country, including the arid and semi—arid areas, as it offers a workable solution to small scale growers who get to enjoy simplified modern inputs at one go.
Companies have also offered training to many farmers from various regions Kenya. Companies hold seminars in which they teach farmers on how to maximize on their small pieces of land by doing greenhouse farming.
We as San Adrean greenhouses company are glad to have held more than ten seminars to educate farmers and to use agriculture to transform lives.
FACTORS AFFECTING GREENHOUSE FARMING IN KENYA
Temperature And Humidity
Many farmers fail to get good profits from greenhouse crops because they cannot manage the two important factors that determine plant growth and productivity. Greenhouse temperatures below 13 degrees Celsius and above 30 degrees Celsius in the case of dry air or higher than 30 to 35 degrees Celsius in cases of high air humidity affect growth and productivity of most crops. The optimal temperatures for production of greenhouse tomatoes, pepper and eggplant should be 15 to 30 degrees Celsius and not beyond 35 degrees Celsius.
The temperatures should be maintained at around 16 to 30 degrees Celsius during the day and 13 to 18 degrees Celsius during the night.
Some tomato farmers close the greenhouses the whole day without ventilation resulting in excessively high temperatures beyond 40 degrees Celsius that lead to reduced performance of the crops. Generally, small-scale greenhouses are prone to overheating when the sun is too hot.
Farmers should, therefore, open the doors and sides of the greenhouse from 8am to 5pm for ventilation and close them at night to reduce heat loss. Greenhouses with only insect nets on the walls are unsuitable for areas with low temperatures like the highlands of Kericho, Mau Narok, Molo and Mt Kenya regions but may have positive effects in hot and warm areas such as Mombasa, Kitui, Kisumu, Machakos and Garissa. Ideally, farmers should have a thermometer for measuring temperature inside the greenhouse for effective management.
High relative humidity resulting from crop transpiration, water evaporation from the humid soil or other growing media and condensation of water vapour on the different greenhouse surfaces is another challenge.
Relative humidity above 80 per cent coupled with high temperatures increases incidences of bacterial and fungal diseases like bacterial wilt and botrytis (gray mold) while greenhouse conditions with relative humidity below 60 per cent and high temperatures create favourable micro-climate for rapid multiplication and development of mites and insect pests.
Humidity in the greenhouse should, therefore, be regulated by ensuring adequate ventilation, maintaining high temperatures at night, using plastic mulching on planting beds and avoid wetting of the greenhouse floor.
Loss of Soil Fertility
This is a common problem as most farmers plant one crop continuously without rotation. This can be overcome by rotating crops, for example growing onions or melons, pepper or eggplant after tomatoes and the use of both organic and inorganic fertilisers to replenish soil fertility.
Farmers can also replace greenhouse soil by bringing quality soil from outside. Adopt the technology of growing crops in pots or soilless cultures. The soils when used continuously with same crop will have a buildup of diseases, especially bacterial wilt, bacterial canker, fusarium and verticilium wilts.
Greenhouse farmers are, therefore, encouraged to treat the soil by sterilisation, solarisation or fumigation using fumigants such as Dazomet, Metam Sodium and Chloroptin.
Greenhouses get contaminated by people visiting the structures or by use of infected planting material, water and farm tools. Have a foodbath at the entry.
Lack of Quality Water Sources
Many parts of the country are deficient of good water sources and rivers or boreholes may also be absent. In addition, available water could be saline, chlorinated or contaminated with diseases like bacterial wilt, hence it is of poor quality.
Contaminated water is common in areas where farmers in sources of water plant crops like potatoes, tomatoes and water flowing downstream is collected by farmers for greenhouse farming. This introduces bacterial wilt in greenhouse tomato.
Pests and Disease
Management of insect pests and diseases is the biggest challenge in greenhouse farming. This depends on the type of the crops that are planted. However, generally, pathogens and insects can be established in a greenhouse very fast. They are very difficult if not impossible to get rid of effectively. For greenhouses that are covered with plastic, the use of ultraviolet-absorbing plastics can reduce insect problems.
Cost of setting up greenhouses
Setting up a greenhouse and the systems that go with it is expensive and posses the greatest challenge to many people who would like to get into greenhouse farming. Commercial banks offer credit facilities but they require collateral to act as security which in most cases are usually not available and also the interest rates charged on this loans make the loans unattractive.
Greenhouse Farming in Kenya – Advantages/Benefits
- Increase in yields depending upon the type of greenhouse, type of crop, and environmental control facilities.
- Reliability of crop increases in green house cultivation.
- Expands the growing season.
- Expands the variety of crops to be grown.
- Minimize external threats to crops.