Syngenta
Syngenta Tenacity Herbicide
Best selective herbicide for maintaining healthy, weed-free cool-season lawns.
This selective herbicide offers comprehensive control for over 46 types of broadleaf and grassy weeds in cool-season turfgrass. It is effective for both pre- and post-emergence applications, providing flexibility for lawn care. The formula inhibits chlorophyll production, causing weeds to visibly turn white within 10-14 days. It can be applied during seeding to reduce weed competition and promote healthier turf establishment. This solution is uniquely capable of selectively eliminating challenging weeds like nimblewill and bentgrass, ensuring a pristine lawn.
$53.73
Owner Satisfaction
4.5
/ 5
Category Rank
173
/ 554
#173 in Herbicides
Price vs Category Average
-44%
Below average
Capacity
8
/ fl oz
Who it's for
- Homeowners managing stubborn weeds in established turfgrass
- Gardeners establishing new lawns from seed
- Users wanting visual proof of herbicide performance
Who should skip it
- Aesthetic-focused gardeners worried about temporary lawn discoloration
- Budget-conscious owners treating large lawn areas
- Beginners seeking a simple, all-in-one application process
Performance breakdown
Weed Spectrum Coverage
Targets an extensive range of difficult broadleaf and grassy weed species.
Seeding Compatibility
Safe for use during seeding to eliminate competition for new grass.
Application Versatility
Effective as both a pre-emergent and post-emergent treatment for lawns.
Coverage Efficiency
Highly concentrated formula provides exceptional value for large residential areas.
Selectivity Precision
Eliminates invasive weeds without harming established cool-season turf grasses.
Visual Efficacy Tracking
Distinctive whitening effect makes monitoring treatment progress simple and clear.
Key Specs
Capacity
8 fl oz
Coverage
Up to 87,000 sq ft
Target Weed Types
Broadleaf Weeds, Crabgrass, Dandelions, Grassy Weeds, Clover
Selectivity Type
Selective
Application Form
Concentrate
Application Timing
Pre- and Post-Emergent
Application Area
Lawns, Bare Ground
Active Ingredient
Mesotrione (40%)
Know before you buy
Yes, Tenacity is safe to use during seeding. It can be applied at the time of planting to help suppress weeds while your new grass establishes.
The white discoloration is a normal sign that the herbicide is working. It indicates that the plant is no longer able to produce chlorophyll, which leads to the weed's eventual death.
Tenacity is specifically formulated for cool-season grasses like Kentucky Bluegrass, Fescue, and Ryegrass. It is not intended for use on warm-season grasses, as it may cause damage.
You can typically expect to see visible results within 10 to 14 days. During this time, the weeds will begin to turn white before they die off completely.
Yes, Tenacity offers residual control for up to 24 weeks. This helps prevent new weed seeds from germinating throughout the season.
You should keep pets and children off the treated area until the product has completely dried. Once the spray has dried, it is generally safe for normal activity.
Still have a question?
Ask Hayley anything about this product before you decide.
Ready to buy?
$54