Pre emerge timing

I too am 2 days past target soil temp of 70. I’m wondering if it’s safe to wait until next week. Maybe some weeds will get through and I’ll have to address it in post.

Read the label on the pre-emergent herbicide you plan to use. Many state to water it in within 2 weeks of application. I assume thereafter efficacy might decrease somewhat, but not eliminated.

Though many weed seeds germinate at soil temps 70 F and lower, they also require soil moisture to germinate. So lack of rain should also hinder germination of cool season weed seeds even though soil temperature might be favorable.

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NO sprinkler system I guess? You can water it in with a sprinkler can't you?

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Not gonna drag a hose and sprinkler all over an acre over several days doing it.

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Can I still put it out whenever we do have rain forecasted or would that be a waste now?

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Weed seeds are present and germinate year round. Pre-emergent herbicides have an efficacy of about 3 months in the Deep South. I personally wouldn’t view it as a waste of product if applied prior to the next forecasted rain event. Certainly there will be some cool season weeds you’ll likely miss, but that could be minimal b/c of dry conditions hindering weed seed germination as well. Your call……

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Can I spread pre emergent after I mow or should I wait a few days after?

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Yes you can apply pre-emergent herbicide after you mow. Pre-emergent herbicides need to moved into the soil where the weed seeds are present, hence the need for watering in after application.

In contrast, many/most post-emergent herbicides are are absorbed by the weed foliage and translocated though the plant, so it’s usually best to wait a couple days or more to apply post-emergents after mowing (more foliage for the herbicide contact) or wait a couple days or more to mow after herbicide application (more time for the herbicide to translocate through the weed).

We've not had rain in 21 days and the centipede and zoysia lawns are parched. I'm a hose dragger and traveled a few times since the last rain.

Since the lawn is stressed I've not put any pre-emergent down for fear of over stressing it.

Anyone else plan on laying pre-emerge that has not yet?

I'm putting mine down Saturday and hoping we get some rain. If not, I'll haul out the sprinklers

Mine goes down today

NO! Never do weed and feed. The 2 applications go down at different times to be effective