Dos and dont’s in greenhouse farming - Daily Nation

Dos and dont’s in greenhouse farming

Friday April 17 2015

A worker tends to strawberries grown in pipes in a greenhouse in Kinangop. FILE PHOTO |

A worker tends to strawberries grown in pipes in a greenhouse in Kinangop. FILE PHOTO | NATION MEDIA GROUP


Greenhouse farming is not a new concept in Kenya, with many farmers growing crops under the system.

However, despite increased uptake of greenhouses, many farmers, including the experienced ones, make several mistakes that lead to huge losses. Here are the common ones.

a) LACK OF TRAINING: A good number of farmers don’t believe in greenhouse agricultural training modules or those who seek training do not concentrate during sessions.

The excuse behind this is that most say that they have watched other people engage in the farming, so they can borrow lessons from them. Farmers need to know that with the ever-changing climatic patterns and every farm being different, training is crucial for any successful venture.

b) FARM MANAGEMENT: For a crop to attain its optimal potential, it requires good care. This includes adhering to the watering regimes and schedules, feeding nutrients and controlling pests or diseases. A farmer should monitor growth of his crops or have someone to do so. Modern farming techniques have made farming an easy activity but this should not mean total neglect of the crops.

c) TECHNICAL SUPPORT AT THE FARM LEVEL: Farmers need to understand the importance of professional input and advice. As an addition to the monthly field visits by agronomists, there are guide books that explain how to take care of crops. One can also get online support. A farmer should seek help always, even when he feels he does not need it.

d) DESIRE FOR QUICK RESULTS: Greenhouse farming has eased field activities, however, this does not mean there will be absolutely no work to be done. The general perception that the crop will grow by itself is misleading to say the least.

In the desperate attempts to achieve even higher yields, farmers are known to distort professional advice accorded to them in search for quick money. Doubling application of some inputs to hasten the growth process is a common phenomenon. This not only stresses the crop but also causes them to fail. What’s more, too much of chemicals will affect the soil.

e) PESTS AND DISEASES: It is important to note that greenhouses decrease chances of pest attack but they do not eliminate them as some farmers believe. Greenhouse kits such as the Amiran Farmers Kit come ready with pesticides that help in controlling inevitable pests such as whiteflies. However, correct application of the chemicals is necessary.

f) SOIL TESTS OR ANALYSIS: Some farmers skip this test without understanding that pathological analysis of the soil is crucial in greenhouse farming. Timely detection of pathogens like bacterial and fusarium wilt and nematodes will help you know what to grow and curb losses.

g) GREENHOUSE HYGIENE: Farmers are strictly advised to limit human traffic into their greenhouses. People might carry bacteria, especially on their shoes into the facility. It is important to have a footbath at the entrance of the greenhouse structure for cleaning feet or shoes before entering the greenhouse.

The outside cover of the greenhouse should be clean and farmers should remove dust from cover to ensure enough light reaches the crops.

h) NOT EVERY PIPE WITH HOLES IS A DRIP LINE: Farmers need to understand that the technology behind quality drip irrigation systems ensures each crop gets the right and equal amount of water and nutrients.

Netafim, the Israeli multinational firm that invented drip irrigation, insists that small-scale farmers need to invest in narrow drip pipes that ensure maximum distribution of water at minimal pressure.

In addition, the system should have valves that regulate the amount of water coming out and prevent dirt from clogging the pipes.

Drip irrigation pipes are important in greenhouse farming since they are the sources of water and soluble nutrients to the plant. The pipes should be flashed on a weekly basis.

The process is to unfold the drip line at the edge of the bed and open the water to flow through. Any debris that may have accumulated inside should be washed out. If clogging persists, farmers are advised to use Superlink, a chemical that dissolves any salts that may have built up in the pipes. Piercing the emitters using sharp objects is prohibited.

i) UNDER IRRIGATION/OVER IRRIGATION: Greenhouse farming uses lesser water compared to the other farming methods. This, however, should not be taken to mean that you shall use no water. Whilst some farmers believe greenhouse crops do not require water from time to time, others over irrigate and flood their crops. Too much of anything is poisonous.

To check your soil for either of the two, scoop it with hand and squeeze. Over-irrigated soil will appear muddy with some water dropping while under irrigated will be dry and the plant is stressed.
j) NOT ALL SEED VARIETIES ARE SUITABLE FOR GROWING INSIDE TE GREENHOUSE: Farmers should understand that seeds are divided into those for open field and for greenhouse farming.

k) IMPORTANCE OF NURSERY SET: The growing media contained in the tray is porous to allow young roots to grow faster and spread easily. The media doesn’t keep water, thus, decreasing the chances of disease brought about by excess water.

The nursery trays allow only for one crop per tray-hole, so the plant does not compete for nutrients. The nursery set allows production of healthy seedlings that grow fast.

Having discussed the common mistakes, here is what to do before you start greenhouse farming.

First, start with soil analysis to test for bacterial or fusarium wilt and nematodes. These three affect tomatoes and capsicum, two common crops in greenhouse farming.

Second, the land terrain of the farm should be even. In regards to size, the standard greenhouse such as the Amiran Farmers Kit fits on about an eighth of an acre. One should place the greenhouse strategically away from too much shade for best results. Farmers should also have windbreakers on the side of the greenhouse.

Third, water should be clean and reliable. Rain harvesting and wells sinking is a welcome idea in this aspect. Fourth, research on market and seasons.

Fifth, seek financial aid to invest in quality greenhouse for better results and taking an insurance cover will help you manage risks. Sixth, invest in farm workers who are well-trained on the basics of greenhouse farming.

Ms Nanjala works at Amiran Kenya