The label is the law. Rates and restrictions below are taken from the product labels listed under Sources. Your product's own label governs; read it before you mix or apply. Mixing calculator · Disclaimer
- Active ingredient
- Iron HEDTA (FeHEDTA)
- Chemical class
- Iron chelate. The label describes the product as a herbicide derived from iron (Fe) that selectively controls broadleaf weeds in lawns.[1]
- Mode of action
- Iron-based selective lawn herbicide; it does not appear in the WSSA mechanism-of-action summary[1]
- Signal word
- NEU1173H Concentrate (sold as Fiesta Turf Weed Killer, Fiesta Lawn Weed Killer and other names): Caution[1]
What you'll see after spraying
Weeds start dying within hours and turn brown or black. Grass blades sometimes darken too, but the label says they recover within a few days to weeks.[1]
It can stain thatch and hard surfaces. Rinse any plants or structures you hit by accident, and stay off the lawn until it dries to avoid tracking stains.[1]
California limits
Several claims are not for use in California, including algae, lichens, liverworts, lawn diseases and the low 12.6 fl oz rate. There the minimum broadcast rate is 5 to 10 gallons of mix per 1,000 sq ft.[1]
Where it is used
Water the lawn well before spraying and skip drought-stressed grass. Don't apply when the daytime high will pass 85°F, or to bentgrass.[1]
Don't spray if rain is expected within 3 hours, and hold off irrigating for 3 hours. Treat the same area no more than 4 times a year.[1]
For thick moss, rake out as much as you can first. A few days after treatment, rake out the dead moss to tidy the lawn.[1]
If you're unsure how your grass will react, test spray a small patch first. Don't apply to newly seeded areas before the seed has germinated.[1]
Products and registrations
| Product | Registrant | EPA Reg. No. | Active % | Formulation | Signal word |
|---|---|---|---|---|---|
| NEU1173H Concentrate (sold as Fiesta Turf Weed Killer, Fiesta Lawn Weed Killer and other names)[1] | W. Neudorff GmbH KG | 67702-26 | 26.52% | liquid concentrate | Caution |
Label rates
| Product | Use | Pests | Rate |
|---|---|---|---|
| NEU1173H Concentrate (sold as Fiesta Turf Weed Killer, Fiesta Lawn Weed Killer and other names) | Home lawns (broadcast spray) | Dandelion, white clover, black medic, English daisy, creeping buttercup, chickweed, plantains, speedwell, thistles, moss | 12.6–50 fl oz product per 1,000 sq ft[1] Mix 5 fl oz of concentrate per gallon of water. 25.2 fl oz per 1,000 sq ft is the standard rate; use 50 fl oz for tough perennials like creeping buttercup and broadleaf plantain, and 12.6 fl oz for moss and easy weeds (not in California). Repeat in 3 to 4 weeks. |
Safety and environmental hazards
People
Signal word CAUTION: it causes slight eye irritation. Prolonged or frequently repeated skin contact may cause allergic reactions in some people, so wash with soap and water after handling.[1]
Pets
The label lets people and pets back onto the lawn once the spray dries. Store the concentrate out of reach of children and domestic animals.[1]
Bees and pollinators
The label carries no bee or pollinator statement.[1]
Fish and water
Keep it out of storm drains, drainage ditches, gutters and surface water. Spraying in calm weather with no rain due for 24 hours helps keep it on the lawn.[1]
Common questions
- Will Fiesta kill my grass?
- It is labeled to kill broadleaf weeds and moss, not lawn grasses. Grass may darken briefly after spraying, but the label says it recovers within days to weeks. Avoid bentgrass.[1]
- How soon can I reseed after using iron HEDTA?
- Label claims say treated areas can be re-sown one day after spraying, and new lawns can be treated a week after the grass comes up.[1]
- How much Fiesta do I mix per gallon?
- 5 fl oz of concentrate per gallon of water, sprayed at 2.5 to 10 gallons of mix per 1,000 sq ft depending on the weeds.[1]
Sources
- U.S. EPA Pesticide Product Label System, “NEU1173H Concentrate (Fiesta Turf Weed Killer) master label label, EPA Reg. No. 67702-26 (EPA-stamped, Apr. 10, 2025).” www3.epa.gov/pesticides/chem_search/ppls/067702-00026-20250410.pdf (accessed 2026-10-06)