Fertilizer dilution calculator

Convert any liquid fertilizer's "teaspoons per gallon" label rate to the volume you actually need — whether you're mixing 1 quart, 5 gallons, or filling a hose-end sprayer.

Convert fertilizer rate

Mix this much fertilizer

2 tsp

Always follow the specific product label. Liquid fertilizers vary widely — a "1 tsp per gallon" Miracle-Gro label is not interchangeable with a "1 tbsp per gallon" Dyna-Gro Foliage-Pro label. Never mix at higher than label strength. More fertilizer doesn't grow bigger plants — it burns roots, accumulates as soil salts, and causes leaf tip burn.

Common dilution references

Maintenance feeding: half the label rate, applied weekly or every other week. This is the standard recommendation in extension publications for indoor and outdoor potted plants. Frequent low-dose beats occasional full-dose.

Slow-release granular alternative: if you're fertilizing in-ground perennials, switch to a slow-release granular (Espoma, Osmocote) once in early spring. Liquid weekly dosing is appropriate for containers and high-feeders like dahlias or roses.

Hose-end sprayers: use the dial setting on the sprayer rather than this calculator. Hose-end sprayers blend at fixed ratios. The label rate already accounts for the dilution that happens in the sprayer.

When to stop fertilizing: stop liquid feeding by late August in zones 5-7. Late nitrogen pushes tender growth that doesn't harden off before frost, causing winter dieback. Slow-release applied in early spring releases over the growing season and tapers naturally.

Sources: Missouri Botanical Garden fertilization guidance, Penn State Extension, Cornell Cooperative Extension.