# Can you put down pre-emergent prior to a week of rain



## Belgianbillie (Apr 3, 2018)

I was going to put it down sunday, but it appears it will rain all of the following week. Would it wash out.

I am putting down starter fert with mesotroine from scotts as i did a dormant overseed.


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## TommyTester (Jul 3, 2018)

Pre-emergent does need to be watered in so you're fine imo.


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## pennstater2005 (Jul 17, 2017)

Are you spraying or spreading granules. If you're spraying and it dries before any heavy downpour you'll be fine. If it's granular and you get a heavy rainfall I believe some could wash away. I put mine down recently and it rained but not heavily.


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## social port (Jun 19, 2017)

That is my understanding as well. If you put down granular preM (be it dithiopyr, prodiamine, or mesotrione, etc) and haven't watered it in, you want the rain to be a very lite. Heavy downpours can wash the granules away.

The best practice is to water it in at the time of application. Once it is in the soil, you are good.


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## g-man (Jun 15, 2017)

Rate of rain is the key. Heavy downpours could flush it out instead of being absorb. A nice gentle rain is great. Which one are you getting?


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