Overseeding in weedy lawn

Most of the weeds like the annual crabgrass will die with the first frost. Mow low, verticut to prepare the soil and then seed. Seed as soon as possible as through September 15 -20 is the ideal time.

Next spring control the crabgrass with a pre-emergent in early April. Spot treat for perennial broadleaf weeds in late winter. Next year treat for the broadleaf weeds in the fall as this is the best time to control.

You will not be able to this fall as the new grass seedlings will be establishing.

Dennis - Johnson County Extension

Seed this weekend. First aerate and/or verticut as previously suggested. Seed and add starter. Water a couple times a day to keep the soil damp, not wet to the point of puddling water. When the new grass has been mowed at least three times, you can treat for broadleaf weeds.

Apply winterizer to help the lawn make it through winter.

Use a quality pre-emergent next spring to keep the crabgrass seed from germinating.

Get a soil test to find your soils needs too.

Check out the MU extension website, or the K-State extension website for great tips and information.

The other blogger is correct about not doing a big lawn project in the spring. The weather is way too unpredictable and the summer heat will often fry the new grass. You really only get one opportunity to do this in KC and that is in the fall, preferably September.

You can overseed now, but aerate and/or verticut first. I'd suggest doing both. The weeds will still be there and may crowd out much of the new seed, but the annual weeds like crabgrass will die later on this fall. Clover and dandelions should be killed now, as they're perennials.

Then plan to start a lot earlier next year. My method this year worked beautifully. I began to kill off broadleaf and grassy weeds in early August when we had a stretch of weather cool enough to do it. Trimec Plus will kill grassy and broadleaf weeds, but not nutsedge. A product called Q4 will do all of them. Use them carefully and follow the package instructions to the letter.

These products have a lasting pre-emergent effect, so you need to use them about four weeks before you plan to overseed. Because I started so early, all my weeds died, dried up and fully decomposed,m leaving a lot of bare spots that I verticut. I also added topsoil and compost to areas with really compacted soil.

If the whole area is weeds, it's easier and lest costly to killo it all off with a Roundup-type product. You can then verticut and overseed after about a week, maybe less. We did that to a large area last fall and had a gorgeous lawn full established going into winter.

After preparing the lawn for overseeding, use a starter fertilizer and a good seed with NO weed seeds or "other crop" seeds in it. One lasting problem with our lawn is the terrible seed used by a landscaper a year ago. It contained a lot of that "other crop" seed, which is a pale green grass that grows faster than the fescue. There is no way we will ever be able to get rid of it. The information on the grass seed label is required by federal law, and better seed suppliers in our area can provide very high quality seeds with no junk in them.

Then water, water, water -- if Nature doesn't do it for you. Our lawn has been completely transformed in the last month and I hope to not have to do this again!! Good luck.

Seed now so you can take advantage of the warm days and cool nights to get the new plants established. Water daily until the new grass gets established.

If you wait until the spring then the new grass won't be established enough and when the summer heat comes the new grass will die.

Planting now gives them the head start they need to survive the hot weather next year.