Pre-Emergent necessary?

Cool season grasses like Kentucky Bluegrass, Fescue & Rye
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BobRoss
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Pre-Emergent necessary?

Post by BobRoss »

I am pretty new to lawn care and have always just used post herbicide. If I don't really have a crabgrass issue, is it really even necessary to put down a pre-emergent? For the most part, my lawn is filling in pretty good and only gets clovers and some dandelions. From my understanding, pre-emergent wouldn't even really help me much.

Also, every spring I get a lot of brown dead spots from my dog over the winter and I try spot grow new grass in these spots. Would this be a concern with pre down?

saidtheblueknight
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Re: Pre-Emergent necessary?

Post by saidtheblueknight »

The best solution to preventing weeds is a thick healthy lawn, which sounds like you have. So if you don't have much crabgrass then you probably don't need any pre-em. But you have to keep up with the other grass and not let it get too thin.

BobRoss
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Re: Pre-Emergent necessary?

Post by BobRoss »

I think that is what I am going to try this year. I overseeded last fall to help fill in bare spots and to add some new TTTF to whatever I have now. I still have 1/4 bag of seed left and was thinking of maybe throwing some more seed down this spring at a much smaller rate. I guess I will have to wait until the snow melts to really know.

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Stuofsci02
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Re: Pre-Emergent necessary?

Post by Stuofsci02 »

Pre-M is dirt cheap.. Worth it IMO even if you don't have a major problem... Just use a rate that is inline with any overseeding you might choose to do in the fall..

BobRoss
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Re: Pre-Emergent necessary?

Post by BobRoss »

you can still overseed after applying Pre-M? I thought that was a no-no.

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Stuofsci02
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Re: Pre-Emergent necessary?

Post by Stuofsci02 »

@BobRoss
You need to wait for it to breakdown. So if you apply in the spring only apply enough so it breaks down before fall overseer.

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social port
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Re: Pre-Emergent necessary?

Post by social port »

I agree with Stuofsci02. I wouldn't skip preM.
You will not be able to grow new grass in the dead spots from your dog (at least in theory). However, some people use a pre-M and later break the preM barrier so that they can seed small areas.

Typically, you can use tenacity to prevent weeds from growing while you are seeding, but application rates become tricky when dealing with small, irregular seeding areas, at least for me.

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Re: Pre-Emergent necessary?

Post by Chris LI »

social port wrote:
Thu Feb 20, 2020 8:33 pm
I agree with Stuofsci02. I wouldn't skip preM.
You will not be able to grow new grass in the dead spots from your dog (at least in theory). However, some people use a pre-M and later break the preM barrier so that they can seed small areas.

Typically, you can use tenacity to prevent weeds from growing while you are seeding, but application rates become tricky when dealing with small, irregular seeding areas, at least for me.
^+1
Another option for the dog spots is to cover them before applying PreM...frisbees, 5 gallon pails, cardboard, etc., might be an option before applying PreM. I would also break the barrier and apply Tenacity at seed down (on the spot seeded areas), to ensure protection while the seedlings are trying to establish. Spring is not optimal for seeding and the dog spots are expected to continue, so PRG might be a consideration for you. I've been helping a friend who has an old dog who can barely make it off the deck, so there are dog spots everywhere. After getting as much kbg down as possible (for beauty and repairability), I'm resorting to PRG in multiple seedings during the year, as sportsfield managers do for high wear areas (between hash marks, goal mouths, etc.).

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