Scaling up organic botanical production in the Upper Midwest

Weed Suppression Results

In 2023, I planned to lay alternative row mulch (Weed Guard Plus Paper Mulch) but due to flooded fields, the decision was made to apply it in 2023 instead due to concerns it would break down prematurely.   The fields flooded due to its proximity to a pond, and to fix this, the pond now contains a pump to redirect water away from the field. Flooding should not be a recurring issue in the future.

The delay in laying the paper mulch gave me the opportunity to collect data on how long it took me to weed each week, and compare to next year with the row mulch.

The land is heavily impacted with thistle and crabgrass, and much of the weeding needed to be done by hand.  I spent an average of 30 hours per week weeding, and was still left overwhelmed with weeds.  It informed me that applying a weed suppressant is a necessity.

In 2024, my fields were dry enough to lay the paper mulch.  Last year I spent an average of 1-2 hours weeding per bed, and with the paper mulch, I only spent about 30 minutes per bed.  It was worth the investment and initial labor.  

Harvesting Results

Building and Using the Harvester

Putting together the Baby Leaf Harvester was very simple, and I was able to complete it in about an hour.  I have no prior experience working with farm implements, so no special knowledge was needed.

I am an average height and build, and I found it to be lightweight and easy to maneuver.  

Harvester Compatibility 

In testing the Terrateck Baby Leaf Harvester I found the diameter and toughness of stems, as well as the density of crop growth, determined whether the machine could adequately harvest without getting jammed.   Unfortunately, it was unable to harvest the majority of the botanicals I grew this season (Anise Hyssop, Mountain Mint, Basils, Shiso, Tulsi, Sage) without almost immediately jamming, but it was mostly successful on mint varieties.  

I found that in dense areas of mint, I had to move the harvester very slowly as to not overwhelm the blades with too much plant material at one time.  In areas where plants were spread out a little more, it easily cut through them. In all, I was able to complete a harvest with the Baby Leaf Harvester in about 25% of the time compared to hand-harvesting. 

Issues and Potential Fixes

The biggest issue I had with the Baby Leaf Harvester was jamming. When a jam occurred, as what I assume is a safety mechanism, the blades would disconnect from the piece of the harvester that would move the blades back and forth so they could cut. Every jam, even one caused by a single stem, would require reconnecting the blades, which was time consuming considering how easily it would jam.

Since the jams were caused by tough or thick stems, I’m hopeful it will work on botanicals in the beginning of the season when they are still tender.  With regular harvesting when plants are young, I will be testing it as a viable option for basil, tulsi, monarda leaf, sage, and others.  I am confident that it will not work for botanicals such as anise hyssop (tough stem) or shiso (thick, juicy stem), as I harvest those crops right before they mature.

Another small issue I noticed was that if moving the harvester over long distances or somewhat bumpy terrain (as fields can be), one of the bolts holding the wheel on would come loose.  It was designed to be easily adjustable, but it’s a little too easy.  I had to check it about every 100 ft and tighten it.

Fresh Yields per Hour By Harvesting Method

* These plants weren’t viable to test with the harvester, as only the flowers were collected

Drying Results

The improvements made to the dryer decreased dry time for the botanicals by an average of 2 days.  I believe this to be due to the botanicals having adequate airflow on the racks, but most importantly due to the dehumidifier that continuously pumped out water.  Last year an old dehumidifier was used, and the drain hose didn’t always work and would need to be emptied manually.

Issues and Improvements

I first tried using the bread racks to dry all of the botanicals, but it didn’t provide enough airflow for dense botanicals, so instead I used them strictly for flowers and plants with low water content (ie echinacea leaves), and they worked perfectly.

I then purchased food safe epoxy shelving for botanicals with high water/essential oil content, and they worked extremely well.  As the herbs dried and shrunk, some of the material fell onto the floor of the dryer. I first tried harvesting one botanical per shelf, but anything that fell to the floor was a loss, because the botanicals would mix on the floor and contaminate each other.  The entire dryer, including the floor, is food safe, so the loss is strictly due to different species of plants mixing together.   This problem was solved by harvesting a large batch of a single botanical at a time for any racks that were side-by-side when I had enough plant material to do so.  This also meant I could use the floor beneath the racks to dry botanicals as well, further increasing yield.

The bread racks did not have the same issue because the botanicals were well contained in trays.

Dry Times

*Cultivated Monarda was infected with powdery mildew, and was removed in 2023.  A limited quantity was foraged from healthy plants around the farm to obtain this data.

Total Yields and Shrink

* Shrink refers to weight lost due to drying and destemming (ie. fresh weight to final processed weight)

Extraction Results

Grinding Herbs

As an optional (but recommended) step, I ground the herbs with the Wondermill Junior hand crank mill.  Using the steel blades that came with the machine, I was able to grind leaves and thin stems into a fine powder.  Crushing them first allowed them to more easily go through the auger, otherwise they would get stuck.  

Thick stems needed to be broken into very small chunks before grinding. It was doable, but not worth the labor in my opinion.  

Creating the Tincture

My preferred method of tincturing is to grind the herb and tincture it in the freezer.  I found it somewhat minimizes the chlorophyll content, but doesn't sacrifice the aroma.  

Chlorophyll is considered by some an undesirable trait in absolutes, mostly because the dark green color will change the color of the perfume. I also find it has an aromatic note that can be described as somewhat green or vegetal.  I personally don't mind chlorophyll, but ideally there would be a way to remove the it.  However, that's not within the scope of my research at this time. 

Filtering the Tincture

Following the method above resulted in a clean tincture that was ready to be extracted.

Extracting the Absolute

Temperature Settings

Below are the results of extracting identical Shiso tinctures on different settings:

Low Setting (Setting 3) - 23 minutes

Medium (Setting 6) - 13 minutes

High (Setting 9) - 10 minutes

There were no significant differences between the aromas on any of the settings, so unless the aromatic material was extremely delicate or heat sensitive, I would recommend using the high setting.  I ran small batches for this test, so I expect the time savings to be even higher between medium and high settings, as the machine takes several minutes to create a vacuum before extraction begins.

Overall Ethanol Loss

During the tincturing process, an average of 13% ethanol was lost, due to being absorbed by the plant material and filters. During the extraction process, an additional 2% was lost.  Overall, expect an average loss of 15% ethanol per run.  

Absolute Results 

* this is an average of at least 5 extractions. Note: chlorophyll accounts for a large portion of this weight

** cost of dried herb and ethanol loss - electricity and labor not included