Production Shade Levels Affect Yield and Vase Life of Elaeagnus

Producers of cut foliages need information on proper production shade levels to maximize yield and quality.  This experiment was conducted to determine the effects of 0, 30, 50, or 80% shade on stem production and vase life of Elaeagnus × ebbingei ‘Gilt Edge’ and Elaeagnus pungens ‘Maculata’.  The experiment was conducted in central Florida where the majority of U.S. cut foliage production occurs.  Elaeagnus were planted in April 2005 and harvested periodically from Oct 2006 through 2009.  Stems used for vase life determinations were stored at 4°C for two weeks and then held in glass containers filled with deionized water.  Containers were held in rooms that simulated the home/office environment.  Vase life was terminated when stems showed signs of desiccation, chlorosis, necrosis or leaf drop.  Significant cultivar × shade interactions occurred for yield (numbers and fresh weights of marketable stems).  For Gilt Edge, more stems were produced under 30 and 50% shade than under lesser or greater shade. i.e., the response to shade was quadratic.  For Maculata, yield declined linearly with increasing shade.  Yields for Maculata were consistently more than for Gilt Edge, averaging 76.5 versus14.5 stems per plant.  Production shade level had variable effects on subsequent vase life.  Overall, Gilt Edge vase life was not affected by shade level but the vase life of Maculata stems tended to increase linearly with increasing production shade level.  Vase lives varied from harvest to harvest but always were longer for Maculata than Gilt Edge.  For all harvests, the average vase lives for Maculata and Gilt Edge were 24.3 and 12.6 days, respectively.  Also, vase lives for both cultivars increased over time as the plants became better established.  The results indicate that producers of Maculata can use shade to increase vase life but at a cost of reduced production.  However, vase lives of Maculata stems grown in full sun averaged from around three to over five weeks in 2008 and 2009, respectively, suggesting that, at least for some markets, increasing the vase life using shade may not be necessary.