On October 10, 2012 we visited the University of Minnesota, Waseca Research Station. We were visiting the ginger growing area at the station to see what type of growing techniques they were using in the considerations for commercial ginger. We walked down to 2 high tunnel-growing facilities. The researchers were growing ginger under different conditions = to calculate the plant=92s phyto-nutrient content of gingerol. The gingerol is used in cancer research by the Hormel Cancer Institute.
The growing beds wer= e prepared with soil of 5 to 6% organic material and 30 - 40% clay. The soil seemed pretty silty to me, but it was = very dry on the surface. The beds are also fertilized with 100 pounds nitrogen p= er acre. Urea is used in the beginning because of the clay soil. The seed tube= rs are purchased from a supplier In Hawaii and look much like the ginger root = you might see in the store. Tis= sue cultures are used in Indonesia for starting plants. The Hawaiian plants are= planted at 6 in spacings 3 to 4 inches deep. Deeper plantings reduce the chances of= a successful harvest. The seed root then sends out rhizomes and begins growin= g new tubers atop the old one. 60 pounds of seed root can yield 600 pounds of ginger root tubers at harvest. These single-season tubers are round and very thin-skinned. They do not look like the usual retail ginger roots from the store. But they taste and contain the same nutrients.
Shade cloth was used over some of the beds. Sections are being tested for growth under shade of 30%, 50%, and 70%. In the deepest shade the plants create more rhizomes but less gingerol per pound. In the 30% sha= de area and in diffuse sunlight under the high tunnel, plants had less foliage= and larger roots. In each case the phenotypic response of the plants produced o= nly the amount of leaf area necessary for photosynthesis. The root, however, being less or more concentrated in phyto-nutrients was relative to the leaf size and overall produced similar amounts of gingerol per plant regardless of sunlight treatment. The more transmissive shade cloth produced less rhizomes but mor= e gingerol. More dense shade cloth produced more rhizomes and less gingerol.
Researchers were also testing different soil temperatures, placing tables at 16 inches beneath the soil surface. Tubers were placed 4 inches above the table, but the depth of the soil reduced plant growth or plants did not emerge at all. Data loggers are used on all the planting bed= s to keep track of moisture and soil temperature. The planting beds are in a double plastic sealed hoop house using an air pump to inflate The space between the layers of plastic and increase insulation. Even with this there was some frost damage early in the fall and it showed on the leaves as light brown striations running the length of the leaf ridges. Ginger seems to be highly susceptible to cold temperatures. High tunnels for season extension are mandatory to grow ginger commercially. Care must be taken in managing the high tile to make sure that the temperature remains consistently high and failures in the structure do = not destroy the crop. In the 2nd high tunnel we visited, row covers were being used to keep the plants warm and reduce frost damage. Row covers and stratifying the air mass within high tunnels can buffer the temperature changes during the night. Larger high tunnels supply more thermal mass and heated air which takes longer to cool during the cold nights. Other storage sources of thermal mass might be recommended for serious commercial production of ginger. Auxiliary heat and dynamic insulation systems would ensure the crop against extreme weather.
Some financial calculations. It seems that Ginger is a profitable venture with season extension. Seed root sells for about $6.50 per pound. 1 pound of see= d stock will plant about 3 feet of soil and yield between 4 to 12 pounds. The Waseca research facility had yields of approximately 10 to 1, but of course theirs is a highly controlled and well managed production space. Some of th= e ginger farms out east are getting approximately $9-$15 per pound for fresh ginger at farmers markets. The 30 x 48 foot-high tunnel in Waseca yielded approximately 600 pounds of ginger root from the 60 pounds of seed group.About a $400 investment yielding anywhere from $5000-$9000 of salable harvest. Not a bad return especially w= hen there are inter-crop possibilities and even a poor harvest would have a good profit.
I enjoyed our trip to Wasec= a to see the high tunnels and the ginger growing there. Just recently we have assembled our own 20 x 50=92 hoop house. I will have to check on= the root depth of ginger but it would seem that raised beds might be an option = for us. Otherwise we also have = a geodesic dome growing space using ground soil that might work well also. </= span>
Posted By Blogger to PERMACULTURE AND PERENNIAL FOOD F= OREST DESIGN at 10/24/2012 09:25:00 PM --f46d042de41b6edd3b04ccd8e930--