The use of large scale greenhouses in Barbados, though a welcome development in the agricultural sector, could be prohibitive because of high operational costs.
However, recent research trials by scientists at the Ministry of Agriculture, Food, Fisheries and Water Resource Management have paved the way for local farmers to utilise a cost effective version of greenhouse technology to cultivate their crops, with increased and bigger yields.
Staff of the Central Agronomic Research Station, led by Agronomist, Stevenson Skeete, have been exploring the use of row covers in the cultivation of hot peppers and beans with some very encouraging results.
The row covers, which can be described as low-cost greenhouse technology, are protective materials used to shield crops from harsh elements including cold, wind and damage from insects. They are placed above crops on a supporting framework often on wire hoops to form a low tunnel and usually left in place until the crops are grown.
The advantages of such structures include: protection from adverse heat, cold and wind and reduced incidence of pest damage.?? In addition, row covers are flexible and can be moved around easily; they increase moisture and humidity; give better yields and crop quality; and the cost of implementing row covers is much lower than installing a full greenhouse.
During a recent Food Crop Research Field Day at the Ministry’s headquarters at Graeme Hall, Christ Church, Mr. Skeete said the results of the research trials were very positive, with findings indicating that the hot peppers grown under row covers were over five times the size of those cultivated in the open.
"Often the improvement is usually 10, 15 or 20 per cent but this one factor of covering the hot peppers in these special shields has given us a dramatic increase," the Agronomist pointed out.
Speaking to an audience which included Minister of Agriculture, Dr. David Estwick, ministry officials, agriculturalists and farmers, Mr. Skeete highlighted some of the differences between the hot peppers which were grown in the open field and those grown under row covers.
He said on average the plants under row covers had a higher number of fruits when sampled, with larger leaves, while those grown in the open were affected by blemishes, damage from birds and bacterial spottiness.
For farmers looking to export their crops, Mr. Skeete suggested that the use of such structures could be a great advantage as the research trials had also showed that the crops produced had better quality and size.??????
"The average fruit size based on weight from the covered plot was 12.59 grams, whereas in the open the figure was about 7.7grams. The average fruit in the open area was not up-to-the-mark for export. You, therefore, have an advantage having the covers on in that most of your fruit will be above and beyond the quality and size for export," he noted.
Mr. Skeete pointed out that the research trials for beans also yielded excellent results. "For beans our experience was also very good. We grew string beans with the cover [on]… and the increase in yields was about 50 per cent more than the ones which were uncovered… the benefits can be seen there," he said.
One of the concerns which research officials had was the possibility of increased temperatures affecting the plants due to size of the row covers. However, tests showed a small temperature variance inside the structure as opposed to the outside.
"By measuring the temperature [we found], it was actually one degree more than the ambient temperature outside and that would vary but the important thing was that there was no increase in temperature under the cover…," Mr. Skeete explained. In addition, tests showed an increase in soil moisture under the covers compared to the open field, which allows the plants to grow better.
The research trials have illustrated that the use of row covers could be quite beneficial to the local agricultural sector in terms of increased crop production and a better quality of fruits and vegetables. In addition, the cost effectiveness and savings made by farmers using this type of greenhouse technology is a significant bonus.
According to the Ministry of Agriculture, the price of the covers on display was approximately BDS $160 while a typical 30 foot by 90 foot greenhouse can cost from BDS $ 12, 000 and up, not inclusive of installation and maintenance costs.
The breakdown for the cost of the row covers was: 12ft by 10ft insect mesh BDS $100 greenhouse plastic $30 Polyvinyl chloride (PVC) conduit (20mm or ?? inch) BDS $25 and drywall screws BDS $5.
Further information on the research trails and low-cost greenhouse technology may be obtained by visiting the Ministry of Agriculture, Food, Fisheries and Water Resource Management’s website at http://www.agriculture.gov.bb/ or by calling the Ministry’s headquarters, Graeme Hall, Christ Church, at 434-5000.