Humic Acid and New Sod Establishment: The Chemistry Foundation Starters Skip
Under Sod 4-2-5 is blended into the top 4 to 6 inches of soil before the sod goes down. The label method is incorporation. If you cannot mix it in, use the quarter-rate topical application.
The rate is one 25-pound bag per pallet of sod (500 square feet), which is 50 pounds per 1,000 square feet, blended into the top 4 to 6 inches of soil.
Great sod needs more than nutrients — it needs the right environment for them.
Humic acid, derived from ancient organic matter like leonardite, is one of the most studied soil amendments in turf science. It doesn't feed the plant directly. Instead, it builds the chemistry that lets everything else work better.
What Humic Acid Does in New Soil
- Chelates micronutrients so iron, zinc, and manganese stay available to the plant.
- Improves nutrient retention by boosting the soil's cation exchange capacity.
- Creates the ideal habitat for mycorrhizae and beneficial microbes to colonize.
- Improves soil structure so water and roots move through it more easily.
For new sod sitting on disturbed, often compacted construction soil, that foundation matters enormously. Without it, even good biology struggles to gain a foothold.
Why it's in Under Sod 4-2-5
6% leonardite-derived humic acid creates the perfect environment for the mycorrhizae and roots to thrive together.
Step two
Day 30: OVER SOD™ 8-0-6 is step two, a phosphorus-free surface feed with mostly slow-release nitrogen, at one 25-pound bag per four pallets of sod (2,000 square feet), which is 12.5 pounds per 1,000 square feet: about 1 pound of nitrogen, 0.75 pound of potash, and no phosphate. Water it in. If day 30 falls inside your state's fertilizer blackout, wait for the first allowed date. OVER SOD™ ships spring 2027. About Over Sod 8-0-6
