CarbonWorks Restore Predicted to Double Sweet Potato Yield

Product Performance
August 9, 2023

We couldn't make up results this dramatic. California sweet potatoes are seeing a huge response with CarbonWorks Restore!

I recently traveled to the test plot at Mininger Farms in California to check on CarbonWorks’ sweet potato trial. This is the first time we’ve used CarbonWorks Restore on sweet potatoes, so I was excited to see how the plants have developed since I last checked on them at the five-week mark.

The trial began when we applied CarbonWorks Restore—CarbonWorks’ starter fertilizer—during sprout planting. We separated the trial crop into three groups:

  1. One group with no CarbonWorks Restore applied (the control).
  2. One group with 2.5 gallons per acre of CarbonWorks Restore applied.
  3. One group with 5 gallons per acre of CarbonWorks Restore applied.

Other than the above application rates, the management of the three potato plots has been identical.

For this visit, we went to the same location in the test plot and randomly selected a plant from each trial group: control, 2.5 gallons per acre of CarbonWorks Restore, and 5 gallons per acre of CarbonWorks Restore. We carefully dug three plants to make sure we grabbed all of the potatoes from each hill, as some broke off while digging. After carrying the plants to the edge of the field where we could get a good look at them, we laid them on the ground to compare the results.

Side-by-side comparison of growing sweet potatoes with vs. without CarbonWorks Restore

What a difference CarbonWorks Restore made on this crop. The control group had, by far, the smallest vegetative growth and the fewest (and smallest) potatoes. They were, essentially, half grown when compared to the CarbonWorks Restore plants.

The plants to which we applied CarbonWorks Restore (both the 2.5-gallon and 5-gallon rates) were very comparable to each other:

  • Both had about the same number of potatoes.
  • The 2.5-gallon-rate plant had potatoes that were more uniform in size when compared with the 5-gallon-rate plant.
  • Vegetative growth for both groups was about double the control group.
  • The 5-gallon-rate plant had, by far, the largest root system and the most root hairs. On this dig, though, it didn't appear that this benefit was going to lead to a yield increase compared to the 2.5-gallon-rate plant.

After we had a chance to carefully look over the three plants I had randomly selected, we met with Nolan Mininger from Mininger Farms to review the results. He was impressed. Nolan’s favorite was the 2.5-gallon-rate plant because of the uniformity, size, and set. (The higher the set on a sweet potato plant, the healthier it is.) He was also impressed with the 5-gallon-rate plant I dug, but said he would have liked to see more uniformity and a slightly higher set. But with any living thing, it’s always good to remember that no two potato plants are going to grow exactly the same.

Next season, Nolan is planning to apply 3 gallons of CarbonWorks Restore per acre and also run another 5-gallon-per-acre trial. No more growing without CarbonWorks Restore! Considering the huge difference between the control plant and CarbonWorks Restore plants, would you grow sweet potatoes without CarbonWorks Restore? Remember: CarbonWorks Restore is not just about increased yields and more robust plants. CarbonWorks Restore improves the environment for microbial life to thrive. It’s a yield and profitability booster that nurtures the environment at the same time.

Mininger Farms is a family operation that grows more than 1,000 acres of sweet potatoes, including many unique varieties such as white sweet potatoes. Learn about their business at

Learn more about CarbonWorks Restore.

George Sims