Lawn renovation: Too late in the fall?

[bperl]

I'm in the Northern Virginia area. I've recently moved to a new home and the previous owner didn't care much about the lawn. The entire lawn is filed with crabgrass (about 95% weeds). Its a .25 acre lot. I've been told its better to just kill all the weeds with roundup and start from scratch.

I've sprayed roundup for the entire lawn about 2 days back. I'm planing to stick to the following plan:

1) Dethatch the entire lawn after all the weeds are dead
2) Spread about 10 yards of compost and some top soil
3) Aerate the lawn
4) Spread fertilizer & lime
5) Overseed the lawn

Since I've sprayed roundup 2 days back, how long should I have to wait before I get started on the over seeding?
I've been told its better to wait about 4-6 weeks before I do the seeding.
I'll be using tall fescue. Will 2nd or 3rd week of October will be too late to do the seeding? I would like to wait as much as possible after spraying round up...at the same time don't want to get too close to winter.

You input is appreciated.

-Kevin

[71ragtopgoat]

It is to late. I would do yourself a favor and get some bids for sod next spring.
If you dont have irrigation you will have nothing but problems with seed. It wont last the summer and your weed problem will be the same as you cant use a pre m while trying to grow grass from seed.

[t608]

Originally Posted by 71ragtopgoat

It is to late. I would do yourself a favor and get some bids for sod next spring.
If you dont have irrigation you will have nothing but problems with seed. It wont last the summer and your weed problem will be the same as you cant use a pre m while trying to grow grass from seed.

What are you saying we only have a week or two to seed? I found for clients sod is harder to maintain then grass seed. The sod never last the summer because of the amount of water need to keep alive.

There is starter fert with pre m in it so spring seeding should be ok however fall is the best time. I have seeded up till last week of Sept with good next spring results.

[Puttinggreens]

Northern Virgina, you have plenty of time.

We are in SE PA and I will aerate and seed for many more weeks with success. I run two crews aerating and seeding every year.

My suggestion, and I do several of these a year. You sprayed Roundup once already. Wait 7 to 10 days and spray again to get anything you may have missed or is not completely dead.

Assuming what is dead will not be that tall I never bother with mowing it down or dethatching, sure you can go ahead and do this but the extra work is not needed. Give it a day or two then aerate the living hell out of it. Seriously, take all the labor you saved by not dethatching and mowing and put it into aeration. When this is finished aerate again. Chew it up thoroughly to create a good seed bed.

Apply the tall fescue at 10 pounds per 1000 square feet. Unless you have grading issues you most likely do not need to add topsoil. However, if you do have a good source for organic matter, a light topdressing will do wonders for improving the soil.

10 days after seeding apply starter fertilizer. Apply a quick release fertilizer again around early November and you will be good to go.

At some point you should get the soil tested to determine your pH. I wouldn't just assume you need lime and guess. the test results will tell you the correct amount needed.

Hope this helps, Ive done it this way for years with great success.

[Smallaxe]

I've seeding in Central WI and getting germination within a week in most cases, but now am drawing to a close...

If it were me I would go out and mow everything down as low as possible and even mow twice if it needed to be chopped finer yet.

Spread the seed next... and cover over it all with compost for quick germination... keeping it soaked for about a week, depending on the soil...

If you did a good job with the RU it has already moved into your roots by now so nothing should be coming back after the mowing... removing all of the dead plant life just doesn't make any sense because it will work as well as straw for seed cover, even better... The weed seeds are there already so removing the debri will do nothing for that...

I'm no expert on NV climate, but I would think you got more time than we do...

[bperl]

Thanks Puttinggreens. I will follow your advice and spray roundup again on 9/19.
So, should I consider Oct 15th as my cut off date to do the new lawn seeding?
Or can I start the seeding as soon as Oct 1st?

[Puttinggreens]

If everything is dead by the 19th start then. If you need to spray again just give it a day or two to be absorbed then go at it.

Roundup will not effect un-germinted seed. You have time but still the sooner you aerate the better.

[bperl]

Thanks. I'm also installing sprinkler irrigation system cause I didn't think I could water the new seeds twice a day if I do it all by myself. The sprinkler system will be installed in couple of days. I'm planning to do the seed bed preparation and overseeding afte the sprinkler system is installed.
What do you guys think is best for seed bed preperation. A lot of aeration or rototiller ?
Does sprinkler system get effected because of either ?

[RigglePLC]

Puttinggreens has very good advice. I wouldn't bother to spray Roundup a second time. Crabgrass(and all summer annual weeds), if you missed any, will die at the first frost--no problem. Since Roundup will not kill crabgrass seed--you will need to apply crabgrass control late March anyway, and again 6 weeks later, to be sure. Both aeration and roto-tilling are a risk to the sprinklers--mark the heads carefully. Bury the wires and tubeing deep. Rototilling makes a mess--you get a lot of clumps of sod to rake out, and haul away, (need dump truck). Puttinggreen is right--use aeration.
Hurry--you want to sow your seed 6 weeks before frost. Seed in fall--not in spring. (Unless you are seeding Bermuda).

Remember Roundup is absorbed and inactivated by soil--no waiting period.
http://turf.unl.edu/pdfctarticles/se...%20roundup.pdf

[bperl]

Thank you for the advice. I'm just worried if I spread 2 inch of compost and do the aeration, the compost might not mix well with the soil. Afterwards if I do over seeding, does the seed has good contact with the soil or would it be just resting on the compost ?