Region: Grabouw – South Africa
Type of Structure: Shade-net structures – fixed and moveable.
Description of Project:
The trials have been running for about 3 years now and have included work with Yellow, Red, Pearl (White Diffused), Blue, White and Black nets over various varieties. All nets used are of a fairly low percentage shade factor of about 15%. The nets used are not decorative in color, but actually change the spectrum of light that is reaching the tree canopy and thus changing the way the tree reacts photo-synthetically to light.
The trials are being run by a company called Two-a-Day, who have various farmers delivering crops to them in a co-operative structure including Oak Valley Estates, Crooks Bothers and about 10 others. Collectively they have thousands of hectares in the area. The monitoring of the trials are managed by their technical team consisting of geologists, botanists and the farmers themselves and we have been very fortunate, not only because everything is being coordinated independently but also that they are monitoring very closely and scientifically.
We have also encountered additional challenges in Grabouw with the weather in that the winds there can reach 140 km/h and we are trying to counter this by using moveable net systems, as the nets are not required over the trees during the winter period and this is the season when the winds are at their strongest.
Because of the professional and academic nature of the work being done we are able to get very accurate and detailed results and this is obviously beneficial for all involved as well as the industry as a whole.
The reason for using nets is different for different varieties, but we have already found that the Blue nets show particularly promising results over the green varieties and the Red nets more so over the red varieties. With a variety like Granny Smith for example, sunburn is a very big problem for the growers and they lose up to 60% of export quality crop. The Blue net here not only prevents the sunburn, but also gives additional advantages to the fruit size, yield etc.