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Home  > Question of the Week

Question of the Week

Permalink What can you tell me about producing okra for value-added processing, particularly pickling?

Answer: Okra is a warm-season vegetable plant in the hibiscus family. It requires rich, loamy soil and a lot of nitrogen. Since it is harvested over a long period of time, it is important to manage weeds effectively throughout the season.

The following are some popular okra varieties recommended by North Carolina State University.

Clemson Spineless is a uniform spineless variety with medium dark green, angular pods. It requires 55 to 58 days from seeding to maturity.

Emerald is a spineless variety with dark green, smooth, round pods. It requires 58 to 60 days from seeding to maturity.

Lee is a spineless variety with deep bright green, very straight angular pods. The plant is a semi-dwarf type.

Annie Oakley is a hybrid, spineless variety with bright green, angular pods. It requires 53 to 55 days from seeding to maturity.

Prelude (PVP) is a new, open pollinated, spineless variety with very dark, glossy, green fluted pods. It can be harvested when pods are ½ to ¾ inches longer and still remain tender. It requires 50 to 55 days from seed and generally yields better than Clemson Spineless.

Value-Added Processing
The University of Florida has developed a web page for canning and pickling vegetables, available at If you have not pickled okra before, this would be a good place to start.

Once you have developed a recipe and processing system, the next step in starting a home-based or small food-processing business is to investigate the cottage food laws in your state. Contact your state department of agriculture to learn more.

The next step in this process is to develop a business plan and profit and loss statement. The U.S. Small Business Administration has produced a useful fact sheet, titled Starting a Home-Based Food Production Business: Making Your Culinary Hobby Your Job, which will help walk you through the steps that you need to take to start a home-based food business. It is available at

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Permalink Can I use livestock manure for methane-electric generation on my farm?

Answer: Most methane-electric generation is from animal waste. If you are accepting animal waste by truck, perhaps food waste or brewery waste can be trucked in as well. This will provide the desired variety of feedstock and will greatly increase biogas production. Manure works because it is readily available and cheap, and it naturally contains the anaerobic bacteria.

The ATTRA website has a section titled "Anaerobic Digesters and Other Biomass Options," which identifies applicable publications and other resources. It is available at On this page, you'll find links to the following publications, which discuss various aspects of using anaerobic digesters:

An Introduction to Bioenergy: Feedstocks, Processes, and Products. This publication discusses how farmers can utilize bioenergy to reduce dependency on petroleum-based energy sources.

Micro-Scale Biogas Production: A Beginners Guide. An introduction to biogas, this publication gives the basics of small-scales anaerobic digester operations.

Anaerobic Digestion of Animal Wastes: Factors to Consider. This publication discusses the benefits and constraints, as well as design considerations, of methane production through anaerobic digestion of animal waste.

A couple good examples of digesters are in Tillamook, Oregon, and New Belgium Brewing in Fort Collins, Colorado. "In Tillamook: Turning (More) Cow Poop Into Power," by Cassandra Profita for Ecotrope, the current digester is discussed, as well as plans for a more high-tech operation:

New Belgium Brewing in Fort Collins, Colorado, uses an onsite water-processing plant to turn brewery waste into energy:

The effluent from the anaerobic digestion should be viewed as a resource. The liquids can be packaged and sold as liquid fertilizer, and the solids can be composted (note: uncomposted solid effluent from digesters "digestate" is not a very good fertilizer). Solids can be removed with an auger conveyor and run through a belt thickener and/or screw press to remove liquids. Composted digestate can be packaged and sold as fertilizer.

Possible negative by-products of methane production are the non-methane components of bio-gas: hydrogen sulfide, carbon dioxide, and water vapor. Removal of hydrogen sulfide is considered essential because the hydrogen sulfide will combine with products of combustion to make sulfuric acid, which will shorten the life of the generator. A thin film of aerobic bacteria can be grown on the surface of the manure inside the digester by allowing about 5% by volume of biogas of air into the headspace of the digester. This will decrease hydrogen sulfide gas significantly. The rest of it can be removed with an "iron sponge." Moisture may be removed by condensing in a conventional air cooled condensing unit or cooling tower. Carbon dioxide (CO2) can stay in the gas stage—it is un-reactive and will pass through the engine and end up in the exhaust. The effect of the CO2 is to decrease the calorific value of the biogas. This is not an issue unless you want to store the gas for some length of time and don't want to invest in the capital cost of gas-holding equipment for useless CO2.

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Permalink I’d like to sell rhubarb to a local bakery. How do I scale up my operation?

Answer: The first step is to develop an enterprise budget for rhubarb on your farm. This is where you define local markets and estimate how much you can sell. It is also important to estimate the costs involved in preparing land, planting, harvesting, and getting the rhubarb to market. This will begin to identify how much rhubarb you need to grow and the price you’ll need to charge. For more information, see the ATTRA publication Evaluating a Farming Enterprise, available at

For general information on commercial production of rhubarb, the publication Rhubarb Production in California, from the University of California Division of Agriculture and Natural Resources, is a great resource. It is available at

With any perennial crop like rhubarb, you ideally spend a season planting cover crops to reduce weed pressure before planting the cash crop. Once you have planted, shallow cultivation and mulch can be used to control weeds and hold in soil moisture. You should take a soil sample to see what nutrients should be used to amend the soil. ATTRA’s Alternative Soil Testing Laboratories database ( identifies labs that perform soil testing.

Rhubarb is a heavy feeder and responds well to applications of manure and compost. It will tolerate slightly low pH and grows well in the 6.0 to 6.5 range. Pulverized limestone, rock phosphate, greensand, and blood meal can be added to the field the year before planting to increase pH, phosphorus, potassium, and nitrogen levels respectively.

If you are happy with the variety of rhubarb you grow now, and it is free of disease, you can propagate plants from the patch that you currently have. This is done by dividing the roots. Each well established plant should give at least eight root crowns for your new patch. Dividing is best done in the fall or early spring, and planting should be done as early in the spring as conditions allow. Common plant spacing for commercial production is two to three feet in row with rows six feet apart. If you locate commercial producers of rhubarb in your area, they may be willing to sell you some root crowns when they divide their plants. Dividing is part of maintaining a productive crop of rhubarb. Many seed companies and nurseries sell rhubarb crowns, and some companies also sell heirloom seed.

If your new plantings grow well you can harvest a few stalks the first year, but harvest won’t truly start until the following year, when you can take a larger portion of the stocks. In three to five years you can start fully harvesting. In certain areas, rhubarb can be harvested once in the spring (April or May) and again in July. Regardless, the plants should be left to re-grow through the summer in order to feed the roots for next year’s production. Some commercial production yields show 10 pounds per plant. This may be a good starting point to determine the amount you need to plant.

The price you set should be determined in part by how much you need to make a profit, and in part by how much rhubarb is selling for in local markets. Bakeries that want rhubarb for their pies seems like a good market, but how much will they need and what are they willing to pay? Will you have to sell to other markets to make the time and financial investment in starting your rhubarb patch worthwhile? These are questions that you should answer before you start this endeavor.

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Permalink Is it beneficial to feed sprouted grain to dairy cattle?

Answer: Grain that has sprouted (if free of mold and other microorganisms) can be fed to cattle with no negative consequence. But in terms of delivering energy and nutrients to livestock, it is generally not advantageous to sprout grains before feeding. Generally, the nutritional quality of the grain is not improved by sprouting them. Germination of the seed utilizes starch (stored energy) that would have otherwise been available to the animal. Since the germinating seed uses up starch, the remaining nutrients (protein, vitamins, and minerals) become more concentrated in the sprouted grain. However, the total amount of these nutrients is not actually higher.

Sprouting can increase the amount of carotene (vitamin A precursor) in grains. Before the development of commercial vitamin supplements, sprouted grains were used as a source of essential vitamins, particularly for poultry during winter months. However, the amount of sprouted grains you would need in order to affect the vitamin A status of your dairy cows is likely impractical, particularly if those animals already have access to pasture or high-quality forage.

You can find much more information on livestock nutrition in the Livestock and Pasture section of the ATTRA website, available at

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Permalink Can plants grown in hydroponic systems be certified organic?

Answer: The National Organic Standards Board [NOSB; the advisory board to the USDA's National Organic Program (NOP)] and the NOP two years ago published a document addressing this question. Entitled Production Standards for Terrestrial Plants in Containers and Enclosures (Greenhouses), this document addresses issues of production including, but not limited to, hydroponics. It includes some of the arguments and reasoning with respect to hydroponics that has been considered by the National Organic Standards Board, as well as specific organic rulemaking change recommendations. Among NOSB's recommendations regarding greenhouse and containerized production, is the statement, "Potting mixtures devoid of or deficient in organic matter capable of supporting a natural and diverse soil ecology are prohibited. For this reason, hydroponic and aeroponic systems are prohibited." The document can be accessed online at

However, there are exceptions. A recent conversation with NOP revealed that there are 17 certified organic hydroponic operations at this time that are certified by USDA accredited certification agencies (ACAs). So, while a proposed rule change by the NOSB recommends that hydroponic systems be prohibited, some such operations, deemed by their certifiers to be compliant under existing NOP regulations, are still certified by ACAs.

It is critically important to understand the relationship between the NOSB and the NOP. The NOSB is an advisory board. While they make recommendations that may guide or lead to regulatory changes by the NOP, they themselves do not have regulatory authority, and their recommendations are just that. See the NOSB webpage at for further description of the makeup and role of the NOSB. It begins with this statement: "NOTE: Recommendations made by the NOSB are not official policy until they are approved and adopted by USDA."

Clearly, the topic of hydroponics remains controversial, with a general notion that if hydroponic systems are to be certified organic, there needs to be additional clarity about the standards (regulations) regarding their certification.

For now, the future outcomes of the discussion are uncertain. At this time, some USDA-accredited certification agencies have certified hydroponic operations as organic, and others have stated that they would not certify them. In the meantime, it is essential to ask certifiers about their current position, and future plans with respect to hydroponic production, and await future clarification from the NOP.

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