By Ron Townsend, M.S., technical services manager for Syngenta

With Tenacity^® herbicide, you can control weeds at the same time you seed. Most herbicide products remove weeds from established turf, but Tenacity can also be used to prevent weeds from germinating in newly seeded or overseeded turf. When grass seed has a chance to grow without weed competition, fall root establishment is stronger, resulting in a healthier, denser turf stand in the spring. Read keys to success to get the most out of your application.

Lawn care operators were asked about their experiences with Tenacity. Here’s what they had to say:

• 97% of those surveyed said they value Tenacity for its flexibility to be used at seeding as well as for pre- and post-emergent weed control¹
• 88% of those surveyed that used Tenacity at seeding said it allows them to seed bare ground without any weeds emerging¹
• 97% of those surveyed said they value Tenacity because it has unique benefits other herbicides can’t deliver (e.g., pre- AND post-emergence, use at seeding, selective control of bentgrass, etc.)¹

Whether you want to overseed in the fall, re-seed bare areas or remove grassy weeds like creeping bentgrass from your turf, Tenacity can help.

Seeding with Tenacity

Tenacity herbicide may be applied to labeled turfgrass species anytime up to, during and after seeding, but prior to turf emergence. Tenacity controls weeds during seeding and provides pre-emergent and some post-emergent control of many weeds. View the Tenacity and Hydroseeding Information Sheet to learn more about hydroseeding with Tenacity.

White means it is working

Short-term, transient whitening may result from Tenacity applications. Its mode of action prevents production of carotenoids in new leaf tissue, a key stabilizer of chlorophyll (green color) in plants. This may also occur in new seedlings of the desired turfgrass species. The effect is temporary and with regular mowing, normal growth of green tissue resumes. The resulting turfgrass stand maintains reduced weed pressure during establishment and helps ensure a healthy stand of grass.

For a complete list of target weeds controlled, view the Tenacity label. Below is a list of some common weeds controlled by Tenacity:

¹Source: TechValidate survey, April 2022. N=33.

All photos are either the property of Syngenta or are used with permission. 

© 2026 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties and/or may have state-specific use requirements. Please check with your local extension service to ensure registration and proper use. GreenCast^®, Tenacity^® and the Syngenta logo are trademarks of a Syngenta Group Company. All other trademarks are the property of their respective third-party owners.