Hi-Yield Atrazine Weed Killer is a product that can only be used on St. Augustine and Centipede grass. It will harm cool-season lawns or other grasses so depends on the type of turfgrass you have.
Hi-Yield Atrazine Weed Killer is only safe on established lawns. Lawns are considered established once they been mowed 3 times.
Yes, Hi-Yield Atrazine Weed Killer can inhibit seed growth of turfgrass, you cannot seed treated areas for at least 6 months after application.
Hi-Yield Atrazine Weed Killer is best applied to a dry lawn but a slight amount of dew is okay as long as not dripping wet.
While it is safe to apply Hi-Yield Atrazine Weed Killer to fully dormant St.Augustine grass, it is not labeled to control rye grass. Sertay Herbicide (Generic Certainty can be used to control perennial ryegrass.
Hi-Yield Atrazine Weed Killer will suppress crabgrass, but it may not completely control it with one application, it can take multiple treatments. The best time to treat for post-emergent control is when the weeds are young and actively growing, usually when temperatures are between about 55 and 85 degrees. Please refer to the product label for a complete list of plants controlled and for full application directions. You will want to apply spring and fall pre-emergent herbicide applications to prevent many broadleaf and grassy weeds from germinating. Here is a great article on crabgrass treatment and prevention as well as one for centipede turf care.
Mixed Hi-Yield Atrazine Weed Killer should be used within a 24 hours of mixing with any type of water as it starts to break down after that time. There is no ingredient in the product to hold it in solution longer.
Per the product label Do not overseed turf areas within 6 months of treatment of Hi-Yield Atrazine Weed Killer.
Hi-Yield Atrazine Weed Killer is not labeled to control spear grass. Unfortunately there is not much information on how to control this grass. You may either consider spot treating with a non-selective such as Roundup QuikPRO - 5 x 1.5 oz. packs or double checking with your extension office to see if they know of anything else that may work
Hi-Yield Atrazine Weed Killer should not be applied near, on or around ornamental plants and flower beds. It should only be applied as directed to actively growing weeds in established Centipede and St. Augustine lawns.
Applications of Hi-Yield Atrazine Weed Killer would need to be kept outside of the dripline of any nut trees.
You could consider carefully spot treating the weeds with a product such as Avenger Weed Killer Concentrate, which is a non-selective herbicide, made from the rind of oranges to control most annual grasses, weeds and broadleaf. Be sure to avoid any contact with the trees themselves or exposed roots.
Hi-Yield Atrazine Weed Killer would be the product to use on St Augustine. Spectracide Weed Stop for Lawns Plus Crabgrass Killer Concentrate states Do not apply to St Augustine on the product label. It contains Quinclorac which St Augustine is not tolerable to.
Pre emergents are applied before weeds have germinated. If the weeds are actively growing, you can continue to treat with Atrazine .