Black Walnut Hulls: Turning Trash into Treasure

2006 Annual Report for FNC05-571

Project Type: Farmer/Rancher
Funds awarded in 2005: $5,847.00
Projected End Date: 12/31/2007
Region: North Central
State: Ohio
Project Coordinator:
Christopher Chmiel
Integration Acres Ltd.

Black Walnut Hulls: Turning Trash into Treasure


As anticipated, this year’s black walnut crop was very small (14,700 lbs) in comparison to the previous year (162,000 lbs). This lack of crop and lack of income plays right into the need to develop the composted hulls into products for those off years.

I’ve made five different piles of black walnut hull compost. The first pile is simply the hulls that have been left alone to compost slowly on their own. The second pile has been turned occasionally with a Bobcat to see if this helps or speeds up the composting process. A third pile has had barn bedding with hay and goat manure incorporated into the hulls. A fourth pile had free wood chips from the local town incorporated into the hulls. A fifth pile incorporated large amounts of shredded leaves, which were also brought from the local town.

I figured that the utilization of free local resources like the shredded leaves, wood chips and barn bedding is a good and realistic model for my self and other farmers interested in sustainability. Plus by incorporating more materials, the compost piles have gotten even bigger, thus having more to sell in the spring.

These different piles may wind up being significantly different products for significantly different uses. The wood chip pile may be a product similar to shredded woodchip mulch that has been dyed. The barn bedding pile may be more of a finished compost product. The leaf pile may be best suited for something else.

This past year I’ve been basically doing some more literature research on compost and walnut hulls. I’ve been finding lists of plants that have been studied for affects of walnut hulls. These will help in the spring, working with the landscaper and organic vegetable grower.

I had a bit of straight, two year old black walnut hull compost left from 2003 to distribute and get utilized. I spread some in pawpaw patches as a light mulch. It appears to break down nicely in the soil, contributing organic matter. Fruit production in these patches seems to be stable or improving.

Ed Perkins of Sassafras Farm, 10940 Lightfritz Ridge Rd., New Marshfield, Ohio 45766 740-664-3370, is a grower at the Athens Farmers Market. He was interested in the idea of substituting the black walnut compost for peat moss in his soil mix. He tried the composted 2003 black walnut compost and thought that his starts did about the same overall. His lettuce might have done a bit better, the broccoli a bit worse and tomatoes seemed about the same. He is interested in trying more experiments with the next round of black walnut hull compost.

Another friend, Mike Kornmiller of Albany, Ohio has a composting toilet that he was using peat moss in. He bought a couple of bags of the composted hulls from me to try. I sold it for about $5.00 per feed sack full, which was half as expensive as the peat moss. It was a rich dark organic material that had moisture and an abundance of worms. Mike was very happy about the idea of using a local product instead of the imported and less sustainable traditional product. He also thought the natural organisms visibly apparent would contribute greatly to the compost process in his outdoor composting toilet. Sarah, Mike’s wife, was not as happy with the black walnut compost, because it was too clumpy and had some appearance issues. I think a product could be developed for this use, but additional drying and processing may be required. Mike suggested mixing in saw dust.

Hank Huggins, a local native plant and gardening enthusiast tried a truck load of the 2003 composted black walnut hulls. He mixed it into beds for raspberries. He says they’re alive and will see how they produce in the coming year.

Doug Albaugh of Stockport also received a bit of the 2003 composted black walnut hulls. We spread it around several blueberry bushes. Doug hasn’t seen any significant changes thus far and predicts it will take years of observation to know for sure.

Green Edge Gardens got a significant load of the 2003 composted black walnut hulls but have not really utilized it as of yet. They are not interested in working further on this project. They say they no longer have the time due to changes in their business. But I believe they also have some fear of the black walnut compost in their soil.

This fear of the black walnut is wide spread. Almost every backyard home gardener has heard of the allelopathic effects of the black walnut tree. It seems to be a part of the local folklore. What this means is that whatever successful applications are developed, sophisticated and educational marketing tools will be needed.

Doing further research on this topic, I’ve run into several more papers. Several lists of plants being tolerant to or damaged by juglones has influenced my focus for developing successful and appropriate markets. I’m hoping to avoid some pitfalls by focusing on plants that have already been successfully cited in existing literature.

Starting in early 2007, I will start some testing of the compost and do some initial soil samples at the test farms.

By the spring of 2007 the black walnut hulls will have composted down a bit and become a bit less intense. Plus with a big new crop of walnuts due this coming fall, room must be made. This stuff will be ready to distribute to the various experiments.

Green Edge Gardens has decided it cannot participate in this project. Willow Run Organics’ Matt Starline, 19197 River Rd., Athens, Ohio 45701 740-707-4122 will take over as the vegetable grower participating in this project. Again, because I’m trying to develop successful markets, I’m hoping to have Matt work on plants that the he grows that are known to do well tolerating the black walnut. Squashes, melons, beans, carrots and corn are all plants that have been observed growing near black walnuts. The solanacaea family of tomatoes, potatoes and peppers should probably be avoided.

Mason Chambers of Five Springs Farm has also been given the lists of plants from the literature review. He will incorporate the different compost mixes into potting soils for trees and shrubs he has selected. He will also build beds at his nursery, utilize the black walnut wood chip mulch and develop the economic analysis piece for his operation.

Doug Albaugh will also utilize the different compost mixes in his blueberry patch and Ed Perkins will try more vegetable start experiments.

I will begin drying on plastic and doing additional processing to bag, label and market this product at the Athens Farmers Market and various local nurseries. This will be a great opportunity to hear consumer reaction to this whole idea and to use this info to create successful instructions, labels and other marketing tools.

By the end of 2007 I will have a considerable amount of experience to draw upon to write the brochure that will be sent to all walnut hulling stations.

At this time, my project is mostly being shared word of mouth with the folks that are participating in the project. I’ve definitely been talking it up with local growers in hopes of finding more interested participants for this project. I talk about it with people at the farmer’s market and other educational events I participate in.

This coming spring when I’m ready to distribute, I will send out a local press release mentioning the grant and the work I’m engaged in. This will also coincide with local distribution of the compost to local nurseries. Along with a label will come educational material about the use of the product.

By the end of the year I will develop a brochure to distribute to Hammon’s black walnut hulling stations all across the eastern United States. This will present some options for marketing and value-adding to the black walnut hulls.