Sustainable Biofungicide for Organic Farms

View the project report

Commodities

• Vegetables: tomatoes

Practices

• Crop Production: biological inoculants, cover crops, fertilizers, foliar feeding, irrigation, organic fertilizers, tissue analysis
• Education and Training: mentoring, networking, on-farm/ranch research
• Pest Management: biological control, biorational pesticides, disease vectors, field monitoring/scouting, mulches - general, mulches - living, mulching - plastic
• Production Systems: holistic management, organic agriculture
• Soil Management: composting, green manures, nutrient mineralization, organic matter, soil analysis, soil microbiology, soil quality/health
• Sustainable Communities: employment opportunities, local and regional food systems, new business opportunities, partnerships, public participation

Organic farming has limited resources for fungal disease prevention, and most options are either expensive or ineffective for treating fungal diseases. In my experience even the most costly solutions ($50+ per acre per application) provide limited results.  We've tried a multitude of organic and natural options over the years with little effect on leaf septoria and other fungal diseases we've gotten on our plants. We want to create an option that other farmers can use that is cheap, robust and effective while also benefiting plant health and soil biology. In addition, all of the biological inputs needed for this project can be grown on a small area with limited capital investment.

Solution:

We will test the effectiveness of our herbal foliar applications. Our foliar spray will be made by aerating our herb mix (lemongrass, holy basil, stinging nettle, sage, bee balm, calendula and comfrey) for 24 hours. This is applied weekly / bi-weekly in conjunction with compost tea. In the past we have used this with great success to prevent disease and we want to quantify if this was luck or actually due to the application of the foliar solution.

The trial will be set up by creating raised beds with a mix of crops we've had difficulty with fungal infections in the past. The best candidate is tomatoes particularly those with later maturity dates. We will also consider using hemp plants due to their high rate of infection. We want to pick the crops that show the least natural resistance to fungal diseases.

Our trail will consist of at least 40 samples of each group for statistical significance. Our groups will be structure as follows:

Group 1: Control - no foliar application

Group 2: Foliar Application - herbal + compost tea 1-2 times per week

We will send in bi-weekly lab tests of both plant tissues samples and soil samples to see how these applications affect both the plant and soil health throughout the growing season. We will also notate and take pictures of the plants from week to week and record the presence of disease between the two sample groups. 

Process overview: 

1. Gather herbs (~5lbs) and add to a 250 gallon tote of filtered water (if using compost tea the tea will brew for 24 hours prior to this using high quality compost). Use a gunny sack to keep the plant material contained
2. Aerate the herbs for 24 hours
3. Strain the solution and fill into sprayer tank
4. Apply the solution with sprayer directly onto both the tops and bottoms of the plant leaves as well as the soil. This will be done early morning or evening. Repeat 1-2 times per week
5. Bi-weekly gather samples for lab testing of both soil and plant tissue

Materials:

the materials required for this project are:

a) herbs - listed above grown in raised beds. For each brew the leaves are clipped with clippers

b) commercial scale sprayer applicator similar to what is used in chemical applications. 

c) IBC tote with high output aerator

Sustainable Practices Used:

Organic / regenerative agriculture - if our process works we are revitalizing the soil while building the natural biology without the need for synthetic fungicides all while staying under the umbrella of certified organic practices

Soil health - our solution adds minerals and microbes back into the soil which should optimize our nutrient exchange capacity and indigenous microbes into the soil

Objectives

1. Quantify the effect of our solution on fungal disease - Does this process prevent disease
2. Quantify the effect of our solution on soil and plant health - are our plants in a more optimum nutrient range with this solution? Is the brix content of the leaf material higher?
3. Assess if this system is scalable and / or repeatable for other grows to use and optimize their operations
4. If successful - create educational videos or seminars to demonstrate how this system can be incorporated by others