By: Eng. Omry Eiger, Netafim’s Greenhouses Activity
Greenhouses enable growers to have greater control over the growing environment of their crops. Greenhouse technology reduces the gap between crop growth requirements and the actual weather conditions where this crop is to be grown.
Statistics indicate that around the world, 70 – 85% of greenhouses are used for growing various vegetables, whereas 15% are used for growing flowers and other purposes.
In the scope of my work in the Greenhouse Division at Netafim, we are often asked by farmers and business investors for advice on whether it is feasible to build a greenhouse in a certain region for a certain crop, and what kind of greenhouse best suits their needs.
Before giving advice, we examine and analyze the environmental conditions in the area planned for the greenhouse, and enquire what kind of vegetable or flower is being planned. This analysis involves studying the environment’s Engineering parameters, Agronomic parameters, and Market parameters.
We specifically look at those engineering parameters in the standards for engineering design, which may affect the load on the greenhouse structure, including:
- Wind speed in the region – Will the planned structure be able to withstand heavy winds? For example, we check if this area has had typhoons in the past 20 years.
- Specific crop that will be grown – Certain crops, as they grow, are tied to the structure of the greenhouse, and add to the load on the structure.
- Snowfall in the planned region – Does it ever snow in this region, and if so, how much and how often is expected?
- Annual precipitation – The annual and seasonal precipitation. In a tropical region, what is the maximum amount of hourly showers, and if this is a dessert area, what is the annual pattern of minimal precipitation?
We also check several agronomic parameters that determine whether the specific crop has potential to grow successfully in a greenhouse in this region, including:
- Environmental temperature – How will the temperature in the greenhouse be affected by a change in season? What is the average temperature, as well as the temperature (minimum and maximum) in extreme weather conditions? What has the weather in this area been like in the past 20 years? We use this information in order to learn the expected weather for the following years.
- Radiation – What is the expected amount of radiation in the greenhouse due to photosynthesis?
- Humidity – What is the relatively humidity in the region? Will it have any effect on the specific crop?
- Water quality – Is the irrigation water in the area of the greenhouse “good quality” or does it require treatment? (PH control desalination)
- Soil analysis – Is the soil in the region suitable for growing, or do we need a different solution?
- Precipitation analysis – Does the precipitation in the region enable growing in a Net House (NH), or should we look into a Greenhouse (GH)? Is there any “heavy rain” season that requires a special drainage system?
As marketing is an important issue, we carefully check several market parameters that determine whether or not the specific crop has potential to become profitable for the customer.
After completing this analysis, we advise on the appropriate solution from the six greenhouse segments available at Netafim. These segments, from the simplest to the most sophisticated, include:
- Simple Net House – The simple net house is a structure that is covered with a net, in order to prevent bugs from entering. It is also equipped with a simple water system. This structure is usually suitable for dry areas with little precipitation. It has no temperature control; during the night, the temperature outdoors is pretty much the same as the temperature inside the net house; during the day, the temperatures indoors and outdoors slightly differ due to the shade created by the net.
- Simple Greenhouse – This is similar to the Simple Net House, but is usually covered with polyethylene walls. This segment is supplied with simple irrigation and natural ventilation.
- Mid Tech – This greenhouse has polyethylene covers, and additional elements that enable growing with temperature control. It comes with windows that can be opened, a screen system, water system, crop management technology (CMT), and electricity.
- Mid-Hi Tech – This greenhouse is the same as Mid Tech, but has the following additional features: air/heating system, growing systems, and hydroponic water system.
- Hi Tech Glass/Polyethylene – This is a greenhouse with a glass or polyethylene cover, featuring advanced systems: screen system, hot water heating system, growing ystems, hydroponic water system, recycling water system, crop management technology (CMT), electricity, and artificial light system.
The lower-end segments are usually suitable for farmers growing vegetables or flowers in a “good climate condition”. For example, in Ethiopia and Kenya, as in Ecuador and Colombia they are predominantly used for growing roses in ideal weather conditions. In Mexico, these low-end NH & Greenhouses are used mainly for growing vegetables in Baja region, which also has ideal weather conditions.
More and more customers are becoming interested in investing in higher-end greenhouses for producing vegetables and flowers. Greenhouses are becoming sophisticated production plants for agricultural products. As we climb the segmentation ladder, the greenhouse costs are approaching business investment levels. Therefore, when we advise these customers on which greenhouse/systems to use, we perform a feasibility study to understand the market, operating costs, and the staff and expertise required. We approach this as if it is a business investment for the customer, and weigh the inputs against the outputs, in order to come up with the most cost-efficient and productive solution for our customers.
For more information about greenhouses, visit our website.
If you have any questions or comments, please send me an email at:
Omry Eiger, Netafim’s Greenhouses Activity