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Home  > Question of the Week

Question of the Week

Permalink What information can you give me on post harvest handling of organic vegetables?


Answer: I am pleased to provide you with information regarding organic post harvest handling procedures for your vegetables.

Peroxyacetic acid (PAA, also called peracetic acid), in combination with hydrogen peroxide, is a popular alternative to chlorine that is allowed in organic production. Like chlorine, PAA performs well in water dump tanks and water flumes. However the treatments result in safer byproducts than chlorine treatments. The disinfection performance of PAA is comparable to chlorine and ozone. To maximize effectiveness, PAA should be maintained at a level of 80 ppm in the wash water. A post-treatment wash with clean water is required for organic standards after a disinfection treatment with PAA.

There is a good publication on this topic available on E-Organic, the Extension online portal for organic information. The title of the publication is:
Approved chemicals for use in organic postharvest systems: In Wholesale Success: a farmer's guide to selling, postharvest handling, and packing produce (Midwest edition).” Silva, E. 2008.

An excerpt from this publication lists organically approved cleaners and sanitizers. I have pasted this list below.
Other Allowed Cleaners and Sanitizers (Suslow, 2000).
• Acetic acid. Allowed as a cleanser or sanitizer. Vinegar used as an ingredient must be from an organic source.
• Alcohol, Ethyl. Allowed as a disinfectant. To be used as an ingredient, the alcohol must be from an organic source.
• Alcohol, Isopropyl. May be used as a disinfectant under restricted conditions.
• Bleach. Calcium hypochlorite, sodium hypochlorite and chlorine dioxide are allowed as a sanitizer for water and food contact surfaces. Product (fresh produce) wash water treated with chlorine compounds as a disinfectant cannot exceed 4ppm residual chlorine measured downstream of product contact.
• Detergents. Allowed as equipment cleaners. Also includes surfactants and wetting agents. All products must be evaluated on a case-by-case basis.
• Hydrogen peroxide. Allowed as a water and surface disinfectant.
• Ozone. Considered GRAS (Generally Regarded As Safe) for produce and equipment disinfection. This is typically cost prohibitive for most producers, however. Exposure limits for worker safety apply.
• Peroxyacetic acid. Water and fruit and vegetable surface disinfectant. (1)

Also refer to the publication “Postharvest handling for organic crops.” It oultlines some the above requirements in more detail.

We encourage all of our clients to check with their certifier to insure a specific sanitation product is allowable by the national organic standards.

Silva, E. 2008. Approved chemicals for use in organic postharvest systems: In Wholesale success: a farmer's guide to selling, postharvest handling, and packing produce (Midwest edition).” E-Extension.

Suslow, T.V. 2000. Postharvest handling for organic crops. Organic Vegetable Production in California Series. Pub. 7254. University of California Davis.
Editor's note: this was written in 2000 and some of the information is no longer accurate. Check with your certifier before using any product.

ATTRA Publication
Postharvest Handling of Fruits and Vegetables



Permalink What are some resources for spelt production?

New York

Answer: I am pleased to provide you with information regarding spelt production.

The following articles provide descriptions of the agronomic requirements for growing spelt. One is titled “Spelt” from the Alternative Field Crops Manual published cooperatively by the University of Wisconsin and University of Minnesota Extension. The next article is “Alternative Wheat Cereals as Food Grains: Einkorn, Emmer, Spelt, Kamut, and Triticale” by Stallknecht, Gilbertson, and Ranney. And finally, the University of Kentucky Extension Service has published an article on spelt.

These resources are interviews or case studies of current spelt farmers. The first is an article from the NorthEast Organic Network’s (NEON) website. This article has photos of Klaas and Mary-Howell Martens and some of their spelt crops. You may want to contact NEON in order to connect with other spelt farmers in your area. Their contact information is:

Anusuya Rangarajan
Executive Director
Department of Horticulture
121 Plant Science Building
Cornell University
Ithaca, NY 14853
Phone:(607) 255-1780
Fax: (607) 255-9998

The next article is an interview with Joel Steigman, a spelt farmer and processor in Pennsylvania. I found this article on the Agricultural Marketing Resource Center’s website at In addition, they have a few other articles on spelt on their website. The AMRC is located at Iowa State University in Ames, Iowa. You can call them directly at 1-866-277-5567.

The last article is from an Ohio website, This article profiles an Ohio spelt grower and some of the food trends that have lead to the popularity of spelt.

Ohio and Michigan are the top producing spelt states in the US. You may want to connect with farmer groups in these states for more information. I do know that Purity Foods is one of the main suppliers of spelt in the country. They may have contacts with spelt growers to share with you. You can contact them at:

Purity Foods
2871 W. Jolly Road
Okemos, MI 48864
Phone: (517) 351-9231
Fax: (517) 351-9391



Permalink What information can you give me on budgeting and marketing for a medicinal herb enterprise?


Answer: Thank you for requesting information from ATTRA on enterprise budget and business planning template for mixed medicinal herb production, and information on how to locate buyers for medicinal herbs, as well as organic seed for herbs.

Enterprise budgets/business planning templates for mix medicinal herb production

Refer to two publications prepared by ATTRA marketing and risk management Specialists that provide useful resources:

Agricultural Business Planning Templates and Resources
Enterprise Budgets and Production Costs for Organic Production

These can be viewed on-line, with live links. Also see the planning template and enterprise budget for mixed herb production, published by the British Columbia Ministry of Agriculture, Food, & Fisheries. (See Resources)

How to locate buyers and organic seed for herbs

Organic seed suppliers

ATTRA has compiled a list of suppliers of organic seed, many of whom can provide herb seed. (
I suggest contacting Horizon Herbs, Seeds of Change, and One-Garden, Inc. (formerly Elixir Farm Botanicals).


Marketing needs to be addressed in your business plan. What scale of production do you envision? There is no one established marketing channel for medicinal herbs. Most herb raw materials for nationally advertised nutriceutical products are contracted for production (often overseas). You may, of course, be thinking of making your own products or supplying local alternative practitioners. The following workbook has been found helpful for any new agricultural start-up business.

Woods, Tim, and Steve Isaacs. 2000. PRIMER for Selecting New Enterprises for Your Farm. UK Cooperative Extension, Lexington.


ATTRA Publications
Herb Production in Organic Systems
Ginseng, Goldenseal and Other Native Roots

Ministry of Agriculture, Food, & Fisheries. 2002. Planning for Profit—Mixed herb crops. British Columbia. 10 p.



Permalink What information can you give me on mycorrhizae and soil health?

New Hampshire

Answer: I am pleased to provide you with information regarding basic information about mycorrhizae and soil health and plant nutrition.

Mycorrhizae are the symbiotic fungi that surround and penetrate plant roots. Studies have shown that these organisms can aid plants in conditioning the soil, as well as help in disease prevention. The amount of plant that form these beneficial relationships, is not yet completely known, but you can get a list at the Mycorrhizal Applications website, a commercial supplier (listed below under further resources). This letter outlines these benefits as well as lists suppliers below.

Soil Conditioning:

A recent study printed in Acres Magazine, showed that inoculation of grass seed with Mycorrhizae formulations, also called AM, doubled soil carbon percentages(1). This study was conducted with perennial grasses, but inoculating a perennial cover-crop seed with AM may increase soil carbon in the soils that you are particularly concerned about from the flooding. Below is a list of a few distributors of AM fungi.

The following article outlines the importance of soil carbon for your farm and how Micorrhizae associations can help with this.
Soil Carbon: A Diamond in the Rough
By, Mike Amaranthus

Disease Prevention
How do mycorrhizae fungi help control diseases? The ATTRA publication I recommend for a review of this topic is listed below along with a direct link.

Sustainable Management of Soil-Borne Plant Diseases

In particular, refer to the section in Sustainable Management of Soil-Borne Plant Diseases titled Mycorrhizal Fungi and Disease Suppression. The mechanisms for biological control, the means by which this symbiotic fungi helps control pathogens, are worth repeating here:

The mycorrhizal fungi protect plant roots from diseases in several ways:

• By providing a physical barrier to the invading pathogen. A few examples of physical exclusion have been reported. Physical protection is more likely to exclude soil insects and nematodes than bacteria or fungi. However, some studies have shown that nematodes can penetrate the fungal mat.
• By providing antagonistic chemicals. Mycorrhizal fungi can produce a variety of antibiotics and other toxins that act against pathogenic organisms.
• By competing with the pathogen.
• By increasing the nutrient-uptake ability of plant roots. For example, improved phosphorus uptake in the host plant has commonly been associated with mychorrhizal fungi. When plants are not stressed for nutrients they are better able to tolerate or resist disease-causing organisms.
• By changing the amount and type of plant root exudates. Pathogens dependent on certain exudates will be disadvantaged as the exudates change.

Two web links outline the above mentioned concepts:

Managing Soilborne Diseases by Managing Root Microbial Communities
Dr. Robert G. Linderman, SARE 2000 Conference Proceedings

The Importance of Mycorrhizal Fungi and Other Beneficial Microorganisms in Biodiversity Projects

Content: Ted St. John paper presented at Western Forest Nursery
Associations, 1992.

Suppliers of Mycorrhizae or AM

According to the Organic Materials Review Institute (OMRI), there are four companies whose microbial products are approved for organic production. The first company listed below, Mycorrhizal Applications, Inc., is a leading manufacture of AM fungi. It is not clear as to whether or not the other companies specifically manufacture AM fungi or other types of mycorrhizae.
Mycorrhorizal Applications Inc.
Dr. Michael Amaranthus
P.O. Box 1181
Grants Pass, OR 97528

Custom Biologicals, Inc.
Mr. Thomas Baugh
1239 East Newport Center Drive Suite #117
Deerfield Beach, FL 33442 (561)998-1699

Amaranthus, M., et al. 2009. Building Soil Organic Matter Biologically: The Benefits of Mycorrhizal Seed Inoculation. Acres USA.

Further Resources:
Types of Mycorrhizal Plants



Permalink What are some guidelines for using paper in compost?


Answer: I am pleased to provide you with information on composting paper.

Paper is considered a good carbon source for compost and can be included in a compost pile. It is best to talk to the farmers who may be taking your paper to see how much they can take. This quantity will depend on how much nitrogen they have available for composting. By having a balance of nitrogen (green materials) and carbon (brown materials), compost piles generate high temperatures needed to create the compost. The carbon to nitrogen ration of compost required in organic production needs to have an initial C:N ratio of between 25:1 and 40:1.

There are some issues to be aware of before adding any paper to a compost pile. According to Jim McNelly, a composting specialist at NaturTech Composting Systems, Inc., the issues involving composting paper include (1):

1. Printed paper contains heavy metals, particularly colored inks.

Information states that since lead printing plates were banned over 25 years ago, that North American paper is free of lead. There may be some concerns about composting old books or paper from countries that still use lead printing plates. Heavy metals in inks are insignificant and are at virtually background levels, certainly far below the EPA 503 rules.

2. Inks are made from hydrocarbons which are a biohazard.

Composting is a technique of treating many hydrocarbons through bioremediation into benign products. Most hydrocarbons have volatilized off the paper long before the paper is composted anyway. Using soy inks promotes sustainable and renewable inks, but has little effect on the safety of paper used for composting.

3. Glossy paper such as magazines should be avoided

It is clay that makes paper glossy and clay is not a biohazard or contaminant to the soil in levels, up to 20%, found in magazines.

4. Chlorine and dioxins are a contaminant in paper

They are both found in all types of bleached paper. Chlorine is a concern
in the production of paper, not in the paper itself. Dioxins have been greatly reduced over the past decades and are in q-tips, napkins, feminine hygiene products, milk cartons, and virtually all bleached paper products. If the dioxin levels in paper, which are in the parts per trillions, are a concern for the soil, then we are at the point where we should be banning all paper products. It is not appropriate to single out composting as a carrier of dioxins. The real culprit with dioxins is incineration, not composting.

5. Paper is a non-renewable resource and should be recycled, not composted

This is the argument of the Environmental Defense Fund which is countered by the position of the Composting Council in 1993 which states clearly that composting is recycling. Recycling paper should occur where it is economically feasible and composting paper should occur where it is economically feasible. Neither is better than the other.

In addition to the issues pointed out above, I would like to add that there are some issues related to composting envelopes. Envelopes contain glue for sealing and some contain plastic. It may be best to avoid envelopes from composting. For more information on composting, visit the U.S. Composting Council web site at:


(1) McNelly, Jim. 2000. Safety in Composting Paper. U.S. Composting Council.



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