Paul from Fairfax, Va writes
For my sized lawn, the gallon would last about 7 years. I can't find anything on the label about whether or not you can store this indefinitely or if it loses potency after a couple years.
Generally, insecticides and herbicides will last 3-5 years when stored in its orginal container and out of extreme heat or cold conditions. Since Headway Herbicide label does not specifically state a shelf life, we would recommend contacting Syngenta directly at 1-866-SYNGENTA.
Answer last updated on: 08/03/2015