G. Stephen Crnko | 12/22/2005 11:33:36 PM
Commercial organic vegetable production is catching on in Louisiana. LSU AgCenter commercial vegetable expert Stephen Crnko shares his strategy for growing a successful organic crop.
The horticulturist planted a set of crops in two different seasons, one in the fall of 2004 and one in the spring of 2005 on a 0.13-acre site in Baton Rouge. He chose vegetable varieties that would yield premium products that would command premium prices. Higher selling prices are necessary to offset the higher cost of organic production.
To prepare the site, he applied 105 cubic yards of compost (equivalent to about 50 tons per acre) in the fall and another 75 cubic yards of supplemental compost (equivalent to about 35 tons per acre) in the spring. The compost had fairly high percentages of nitrogen (N), phosphorous (P2O5) and potassium (K2O).
Crnko set up a drip irrigation system for water and fertilizer and to minimize pest problems.
He followed organic production guidelines outlined by the Louisiana Department of Agriculture and Forestry, which offers a three-year organic production certificate program. He used natural fertilizers and pesticides, according to approved fertilizing and spraying practices.
His fertilizers included a natural fish oil, which contained 5 percent N, 2 percent P2O5 and 2 percent K2O; Chilean Bulldog sodium nitrate, which contained 16 percent N; and Epsom salts and calcium chloride.
He applied the fish oil at a rate of 15 quarts per acre, the sodium nitrate and Epsom salts at a rate of 31 pounds. per acre and the calcium chloride at rate of 7.5 quarts per acre.
The vegetable expert used plastic mulch to limit weeds, control diseases and minimize pest problems, plus to accelerate growth.
He staked and tied crops that needed support. This practice enhances yields by limiting diseases and insects.
He controlled weeds primarily by hand plowing, hoeing and hand-pulling. He used the chemical kocide to control early blight disease on cucurbits (melons, squashes) and tomatoes. He used pyrethrins (natural pesticides), horticulture oils, ultra fine oils and Bts (microbial pesticides), such as Dipel and Condor to control insects.
Crnko’s fall garden consisted of artichokes, beets, broccoli, brussels sprouts, cabbage, carrots, cauliflower, collards, garlic, lettuce, mustard, onions, shallots, spinach and turnips. These long-term crops should be planted in the fall and harvested in spring.
He realized some success with the artichokes, shallots, onions and garlic. Overall, though, he was not pleased with the results. He discovered that the crops did not do well, because the compost had not completely decomposed.
By spring, the compost had decomposed and released nutrients. After he applied the supplemental compost, he was ready to try again. He planted artichokes, bell peppers, cantaloupe, cucumbers, eggplant, Irish potatoes, jalapeno pepper, okra, pole beans, southern peas, squash and tomatoes. This time, the harvest was close to commercial grade.
For those interested in organic vegetable production, Crnko passes along several observations from his experience.
1. Commercially produced organic vegetables are possible in southern Louisiana. He recommends raising artichokes, shallots, onions, garlic, Irish potatoes, pole beans, squash and bell pepper.
2. Supplemental compost, with organically approved fertilizers, is very important for quality plant growth, especially with the first crop after initial application of compost.
3. Actively growing crops help reduce pest problems.
4. Isolate certain crops from one another. For example, isolate the onions, garlic and shallots from the other crops to prevent the buildup of thrips. These insects thrive on green and actively growing crops in the spring.
5. If pests get ahead of you and cause a lot of damage, it is best to get rid of the host crop.
6. Normally, organic gardening is an expensive production system. To make money, you have to have a premium quality product and obtain a premium price for your product.
For related horticulture topics, click on the Lawn and Garden link at the LSU AgCenter Web site, www.lsuagcenter.com. Additional yard and garden topics are available from an extension agent in your parish LSU AgCenter office.