Check the label on the herbicide as it varies with several factors-type of herbicide (was it pre-emergent, or post) time of year, rainfall after application, plants going in after herbicide application, dosage used in application.
You should be able to find out from the company website if you've discarded the container, or don't have one because you got the herbicide from someone else, and they gave it to you in a jar with a handwritten note telling you how much to apply, etc. Google the manufacturer and look around the site to find out more information on the stuff you used.
Going forward, you may find it helpful to keep a log of herbicide and pesticide applications. Write down the date, weather conditions, dosage rates, area treated, and finally results like how long it took for everything to die off. This information will make it easier for you to plan future treatments and applications, and you'll know what worked to get you a successful harvest-whether that harvest was veg, fruit, florals, or other landscape plants.
Also, sometimes companies change (they call it improved, lol) their formulas, and the stuff that worked so well last year that you used up the whole bottle doesn't work quite the same way this year with a new bottle.
So always read the label, log your data, and keep the container until you have successfully harvested a new crop from the beds you applied the herbicide (or any garden treatment) to.
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