For general annual weed control, a common mix is 2.5 fl oz of Cornerstone Plus per gallon of water (assuming a carrier rate of 1 gallon per 1,000 sq ft). For tough perennial weeds or brush, increase the rate to 5 fl oz per gallon. Always check your specific product label, as formulations like Cornerstone Plus 5 (50.2% Glyphosate) may have slightly different application rates.

Cornerstone Plus typically contains a built-in surfactant or adjuvant, meaning additional non-ionic surfactant (NIS) is not strictly required for most applications. However, when treating weeds with thick, waxy leaves (like bindweed or ivy), adding a small amount of NIS (0.25% v/v) can significantly improve herbicide uptake and effectiveness.

Cornerstone Plus is a systemic herbicide, meaning it must be absorbed by the foliage and transported to the roots. You will typically see initial yellowing and wilting within 3 to 7 days. Complete browning and death of annual weeds usually occurs within 1 to 2 weeks, while tough perennial weeds may take 3 to 4 weeks or longer to fully die.

Cornerstone Plus (Glyphosate) has no residual soil activity; it is inactivated immediately upon contact with soil minerals. This means you can safely plant most crops, grasses, or ornamental plants just 1 to 3 days after application, once the spray has completely dried and the herbicide has reached the target weeds’ roots.

Cornerstone Plus is safe for pets and children once the sprayed solution has completely dried on the foliage. It is highly recommended to keep pets and children off the treated area during application and until the spray has fully dried (usually 1 to 2 hours, depending on weather conditions). Always store the concentrated product securely out of reach.