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grass seed after weed control

This type of weed killer is very effective and garden-friendly. It takes about one month after application for sowing your grass seeds. These herbicide destroy broadleaf weeds as well as grassy weeds. If the desired plants are in a grass family it may destroy them and it does not take off any evidence on the soil. These herbicides are fairly effective to kill broadleaf weeds. As I said, probably you may wait for about one month but you must follow the instructions that are labeled in the herbicides. Some examples of selective weed killers are given below.

You may be noticed that different opinions are available for weeds on the basis of the chemical composition of the herbicides. You must find that multiple numbers of weed killers are available in the market and the degree of poison is varying. So, you have to decide on which weed killer you wanted to use and how long after the application of the weed killer you wanted to sow grass seed. So, at first, make sure about which composition of herbicides you wanted to use.

Before going to plant grass we need to know the following things.

Selective weed killer

All traces of herbicides must need to eliminate before the planting of new grass seed. If you make any foolish decision of planting seeds before its removal you must have to disappoint as your seed might not germinate well. You need to be very careful about this when you use any kind of pre-emergence herbicides.

These are very effective to control weeds by killing them in their initial stage. They prevent weed seeds from sprouting by creating a chemical barrier in the soil surface, also it kills the grass family. These types of herbicides take about four months to wait after the application to sow the grass seeds. You must wait until the full decay of it.

This is a very effective and well-known herbicide as many users prefer this type of herbicides. This is a non-selective weed killer in the systemic group. This herbicide kills all the weed plants entirely with roots. It does not leave any remaining part or residues of deed plants in soil. The herbicide can kill a different type of plant-like grass, weed, and undesired plants but once it absorbs completely by the soil it does not impact other plants. It takes only three to four days to wait for planting or seeding new grass.

It depends largely on different types of weed killers. Though few of those take several months, many of those take a few hours to a few days. You can make sure about it if the composition of the weed killer is known. So, first of all, you have to introduce different types of weed killers that are available in the market. You must make sure about the specific time of sowing your grass seeds. Here, I am going to tell you the time of sowing grass seed in a different type of weed killer.

Can I Spray Weeds and Kill Crabgrass Now if I Plan to Seed In September/Fall Time?

Let’s stick with our example of Kentucky Bluegrass and you can see that it’s ok to apply quinclorac to the lawn to kill crabgrass 7 days before seeding or more. So right now, if you are let’s say 2 weeks away from seeding, you are welcome to spray away and kill that crabgrass dead. (note, this product turns crabgrass orange/red in about 6 days. But it takes much longer for the crabgrass to fully break down so likely some of it will still be there when you seed, just red and dead).


Key: The answer to your question is on the label. Labels of weed control products almost always tell you the wait time until seeding after application. Let’s look at two that you likely may be using.

Reading The Label – Quinclorac 75DF

This is where it sometimes gets confusing so follow along with me.

I’m not sure where you are, and I know that even 200 sq feet is quite a space, but really, you should remove everything that’s there, dig it over, getting out the roots of the clovers and any other pernicious weeds with deep roots, and any large rocks/stones, emend the soil if it needs it, walk all over it on your heels to get out soft spots, rake it up lightly to leave a fine tilth for the top inch or so, then either reseed or lay turf (sod if you’re in USA).

Glyphosate (Roundup) works by being absorbed through the foliage, and is neutralized by contact with soil. It will take a few days for the weeds to die – if they are growing slowly because of cold weather etc, they will take longer. By the time they are dead you can safely re-seed. Some people would say it is safe after 24 hours, but you then have the problem that you can’t clean up the dead weeds without damaging your new seedbed.

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The next critical thing you need to do once per year is aerating! Pulling plugs of sod and soil out of the lawn then allowing them to stay where they fall. This is another piece of equipment to easily rent. Share this expense with your neighbors and have an annual PARTY!

I was going to spray with “Ortho Weed-B-Gon Max”, then spread some top soil and reseed, but I’m not sure if that’s the right course of action.

Next let’s talk about WHY this happened to your lawn. You most certainly have cool season grasses. Always a mixture of species. Make dang sure that the label of lawn grass seed states zero weed seed.