In the Piedmont region of North Carolina, a long-running gardening blog tests Soil3, a 100% organic compost made from grass clippings, wheat straw, and cow manure with a high-heat composting method and added mycorrhizae. The tester received a free 1200-pound bag delivered by a local sod company, then ran a side-by-side comparison with a local compost on identical spring greens and vegetable beds.
What Soil3 Is and How It Is Made
Soil3 is 100% organic compost comprised of grass clippings from a sod farm, wheat straw from a farm, and cow manure from a local dairy. We compost using a high heat method (160º) and add mycorrhizae. The bag is very large and heavy, weighing about 1200 pounds, and is delivered by a machine that lifts and places it near the garden rather than at the gate. The compost tends to be quite soggy upon delivery and forms small clumps that break down after tilling.
Delivery Experience and Usability
The delivery process involved a wide bag that could not be maneuvered to the gate, so the bag was placed at the end of the driveway beside the walk to the house. The bag’s sheer size created a logistical hurdle for offloading: it required wheelbarrow shoveling, and the tester had to work around the bag’s height to access the compost. A plan was needed to move and utilize the material efficiently, especially given the timing and space constraints in a home garden setting.
Terse Comparison: Soil3 vs Local Compost
A controlled comparison was conducted on two adjacent halves of a long vegetable bed: identical greens, including lettuces, spinaches, and Asian greens. Soil3 was mixed into one side and local compost into the other before tilling. The Soil3 material appeared darker and clumped into tiny balls, likely from moisture on delivery. After tilling, those balls broke down, yielding a slightly finer texture on the Soil3 side compared to the local compost.
Both sides were prepared with metal hoops to support garden cloth fabric for frost protection and planted in mid-to-late March after starting in a greenhouse. Growth rate and flavor were indistinguishable between the Soil3 and local compost sides at early stages, and both bolted from heat at the same time in early summer. Yield, disease resistance, and flavor showed no discernible differences in tomatoes and peppers grown in comparison beds with the two composts side by side.
Product Performance and Garden Management Implications
Historically, local compost has been used as mulch to suppress weeds and slowly enrich soil nutrients throughout the growing season. In contrast, Soil3 did not function as a weed-suppressing mulch in the same way, and it did not confer any noticeable productivity or flavor advantages over the local compost in the tester’s garden. By mid-May, spring greens on both sides were bolted and bitter, indicating similar responses to spring heat and seasonal timing.
The tester noted one practical limitation: the bottom layers of Soil3 were wetter, making handling and shovel access more challenging, particularly for gardeners under about 5’10”. Despite retying the bag after every use, remaining compost in the bag remained extra wet, indicating moisture-related handling challenges as the bag emptied.
Additionally, the delivery representative suggested Soil3 can be applied as lawn fertilizer, though distributing a 1200-pound bag evenly would require heavy machinery, which is often not feasible in typical home landscapes. This guidance aligns with the observed handling hurdles and the need for appropriate equipment to apply large quantities evenly.
Bottom Line: Should You Buy Soil3?
Overall, Soil3 was not found to be better or worse than local compost in terms of vegetable productivity. In terms of usability, Soil3 proved more difficult to use due to its massive bag size, weight, and moisture content, which hindered easy extraction and transfer to the wheelbarrow. The conclusion drawn from the field trial is that Soil3 is expensive relative to local compost, offers no measurable improvements in crop performance, and poses practical challenges for home gardeners. Based on these results, the author would not purchase Soil3 for a personal garden.
For readers considering Soil3, weigh the cost against its practical handling requirements and compare to trusted local compost options. If your garden setup can accommodate large-scale deliveries and you have the equipment to spread or shovel heavy material evenly, Soil3 may still be a viable option in certain contexts. Otherwise, familiar local compost sources remain a reliable choice for consistent soil improvement and garden productivity.
- Delivery challenges: Very large bags require suitable equipment to offload and spread.
- Texture and workability: Moisture content can affect handling and tilling experience.
- Product performance: No clear productivity or flavor advantage over local compost observed.
In practice, gardeners prioritizing ease of use and consistent performance might favor local compost alternatives, while those with specific needs or access to heavy equipment could consider Soil3 after a careful cost-benefit assessment.