First off, you should understand that a weed is growing there because the soil is poor and the weed has no problem pushing out any grass that wants to come in.
And, if you cut a weed...and not get the root....it comes back stronger and bigger than it was before. So, when you just cut them with your mower, you are doing them a favor.

You don't want to use chemicals. When I hear that from some people who I think don't realize the importance of just what chemistry has done for us I recall a well-known ad from an American company...
:better things, for better living.....thru chemistry.

Your wish to not use chemicals then brings up the need to learn about "organic" gardening--natural methods of controlling how your soil grows plants.
That is a long-term fix.

The amount of soil problems will determine what you have to do.
Fist off I'd say your soil is under-nourished. You could get a soil test done. Your local state funded college extension service is your best bet or possibly the local full-service nursery may do these tests.
Soil tests generally will tell you what your soil needs to perform what plants you have in mind.
If you do decide the job of getting rid of the weeds by inorganic method you can resort to the use of "Roundup"...a non-selective weed killer that will kill anything and everything green.
It does allow you to re-plant within a specified time--usually about 3 weeks.
Other broadleafed weed killers kills most weeds, but leaves the natural grass unharmed.

I would recommend you do a complete aeration of the area with a rented machine. This removes plugs which can help relieve compacted soil. Then the plugs are allowed to compost back into the soil.
Overseeding of grass (you choose the proper type) followed by topping of a good topsoil or compost spread 1/2" over the entire area every spring, every fall.
This builds organic matter into the soil which promotes growth of grass and other plants.

Depending on the size of the area, this can be rather expensive so the need to find a trusted soil dealer comes into the picture.
Then proper watering and fertilizing can help bring you the lawn you desire. Again, staying 'organic' not using chemical fertilizers, can delay your lawn result.

Do some research yourself about "organic gardening" and what that entails. You may wish to re-evaluate your wish to not use chemicals.

The juniper roots that are still there are sending up stems and will continue to do so for a time but eventually will die off. Just keep cutting them with the lawnmower.

If you decide to sod the area, you must get rid of any grass that is there. Sod will not root if it has to fight its way past grass roots already there.

Digging up the area, turning it over, you should then add at least 6" of good topsoil (compost preferably) and turn that under. Weeds can be removed as you unearth them and yes, any weed roots missed will come back.
You could treat them as you see them. If hubby has a propane torch, you can burn them out.
Short term methods can also employ something that burns the roots. Window glass, letting the sun d the work, laid over the area will kill the weeds in no time. Vinegar will kill weeds but will also affect nearby greenery.
Overlaying of a material that prevents sunlight can also work. But this method is long-term.

goren and I disagree a lot so you'll have to try to discern the issues and decide for yourself.

The time to seed is in the late summer. Where do you live? There might be an exception. Generally, though, this leaves sodding as your best alternative at this time.

Never add more topsoil unless you are trying to correct a poor drainage issue. Why? Because adding top soil always changes your drainage. Usually it makes things worse because the topsoil was not needed to begin with. I drove by a house today that had its lawn 5 inches higher than the concrete and the adjacent lawn. They have probably top dressed every year like goren suggests. If you only top dressed 1/2 inch per year, it would take 10 years to get 5 inches too much. Top dressing is on my list of no-nos for lawn care. Here is a picture of a different lawn where they have had to install borders to keep the top soil from flowing onto the sidewalk.

{{gwi:120729}}

Your woody juniper stems are actually roots, still in the ground, correct? They should not be growing. Once you cut a juniper off at ground level, it is dead.

How big an area are we talking about? I'm thinking about tools you can use for larger areas to prep the soil for new sod. Do you have more than 5,000 square feet? More than 10,000? And we really need to know where you live.

I don't see any reason to aerate either. You did not mention that you have hard soil, but even if you do, there are much easier ways to soften it than bucking around behind a 700 pound aerator. Search this forum for "shampoo".

Using organic fertilizer will absolutely not delay your lawn. In fact you can apply organic fertilizer every week if you think it is getting behind the neighbor's lawns. Nothing will speed up the establishment faster than repeated organic fertilizer. Go to the Organic Gardening Forum, find the FAQs, and scroll to the bottom of the list. There you will find the Organic Lawn Care FAQ. It gives you an orientation to modern organic gardening. It is the first update on organic gardening since Rodale first started writing about compost in the 1930s. The modern approach skips compost and goes straight to the ingredients in fertilizer. You can buy them at your local feed store for about 1/6 the cost of regular organic fertilizer and about 1/10 the cost of compost.

There is no great organic solution to killing weeds. If you want to get this done fast, RoundUp is the best way to go. You have to be careful because it kills everything it touches. This means apply on a calm day to minimize over spray on other plants. Spraying vinegar has the same over spray effect. A foliar spray of vinegar kills top growth but leaves a lot of roots alive. RoundUp does not. Once you get the weeds killed, you should never need to use chemicals again.

I'm not real big on soil tests except where there are obvious issues. If you decide to get one, the $20 test at Logan Labs in Ohio is going to be much better than any test from a university. The only exception to that is the lab at UMASS where their test is about on par with Logan Labs.

I'm with Dchall on this one as well (lots of disagreement with Goren's post, I don't know if he/she carefully read your original post honestly). Weeds are growing there because THERE IS NOTHING TO COMPETE for the sunlight and nutrients! But now that there are a large number of weeds, organically "fighting" them would likely be a losing battle or a very long war.

Go organic AFTER, but kill the bad stuff with RoundUp first. Then seed TODAY (or hopefully you already did), with a fast sprouting seed. Rye is the quickest but will only last until late spring next year, so it's more of a temporary fix. Fescue is the best option in your zone and timeframe but it still is going to be risky due to the amount of time you have before a hard frost. KGB is completely out this year. Dchall's recommendation of sod is definitely the best option though. Very pricey compared to the other options, but if prep'd and watered properly will give instant great results.

Basically a month ago you would have a lot of options, but this time of year even a zone lower (where I am) would be flipping a coin as to whether you could get new seed to be hardy enough to deal with the winter. Compounding this is the theory that we are going to have a much harsher winter than the very mild last winter (some of my crabgrass didn't even die!).

My personal recommendation if sod is too expensive, is to use a mix of fescue and ryegrass, get a nice, pretty, dense lawn super fast, but realize come spring/fall you need to heavily overseed with a proper grass (depending on how well the fescue germinated as the rye dies in the summer). Not ideal (spring seeding is never ideal, and very difficult to manage organically), but you pretty much have few options this late in the year.

HTH

Hey all! Thanks so much for responses!!!

We live in northern Virginia (zone 6b). Unfortunately, we have not gotten around to seeding this area yet, as this is not the only thing we are trying to accomplish this fall in the garden. So I think our revised plan is to get this in shape in spring. Like enigma mentioned, I am figuring it is too late to seed for the year and expect them to survive the winter (Although we seeded some patchy spots in the lawn about two weeks ago and they just started germinating beautifully - I think Sandy gave the lawn a good soak).

So with the REVISED plan to get the lawn going in the spring:
1) Would you have a different plan/advise for me?
2) What can I do NOW to make things easier in the spring?
3) Should I seed vs. sod? Since area is not too big, we should be able to afford sod if that will make our life much easier..
4) When should I seed or sod next spring? I assume early spring like March?

I have a lot of dandelions there now, which we try to get the root whenever we see them. Some other things, we also try to get the roots out when we weed. But there are a lot of them, and our neighbor has a backyard full of weeds (some of them has become trees) - she does zero care for her yard, it's pretty much full of weed, yup) and lots of things blow in from there. Does round up stay in the soil? I would be fine tolerating weeding some from the lawn (rest of our lawn has some weed that we need to yank out but not too bad) but if it will prevent the lawn from establishing at all, I guess I would consider. But I would really like to prevent chemicals. We also put in raised vegetable garden near that area (doing lasagna now for next year) so I really do not want chemicals.. I am not expecting/wanting a perfectly manicured lawn, something to get us started and get going, that is not harmful for our family.

Area is not that big at all - we are probably talking less than 1,000 sqft so not too bad. It's easily workable manually by 1-2 people.

I do agree with dchall and enigma that the soil doesn't seem to be a problem. there wasn't much weeds there before we took the Juniper out. And Juniper was doing really well there. Juniper is not stemming anymore and most of them are underground with exception of few sticking out so I guess I will just leave the roots alone based on your advices.

Our soil seems to be normal - not too clay nor sandy, but I am new to this. But it is not much different from what I see in my other flowerbeds.

When is soil test needed? Do you think I need it for this purpose? Or it would be ok to try other methods you suggested first and get tested if I am not making progress?

I will definitely visit the organic gardening FAQ!

thanks all!!

If you don't care about having the perfect lawn, and grass seems to grow for you, then you probably don't need a soil test. If you have persistent problems, sometimes a good soil test (not from your state university or county extension agent) will help resolve the issue. One thing it can help with is the amount and quality of lime to add every so often. Most people guess at this and use the wrong type of lime. That can lead to the formation of clay-like soil when there is no real clay there.

If you can afford sod, don't even think of seeding - especially in the spring. There are two reasons why not to seed in spring: 1. you'll have a dead lawn in July. New seed sprouts do not have the time to develop and harden off before the summer heat cooks them; and 2. you'll have a lawn full of crabgrass by August. Both of those are direct results from spring seeding. Crabgrass seed sprouts in the spring, not the fall. That is primarily why spring seeding is doomed to failure.

RoundUp does not seem to persist in the soil. After 50 years of using it around the world, there are just now some studies showing some issues under certain conditions. I am about as organic as you can get, but if I had a real issue, I would use RoundUp. It will prep your yard fast and easy. Apply once and water as if you were sprouting new seed. The new seed will sprout and then hit the new seedlings with another dose of RoundUp a week later. Then put the sod down.

When you put the sod down, be sure to roll the sod down. Roots will not grow through the air to reach the ground. Then water briefly, 3x per day, just enough to moisten the bottom of the sod so the new roots will start knitting into the underlying soil. Once the new sod is knit in, start backing off on watering frequency and go up on the time. Ideally you will water once per month in the cool months (like spring) and once per week in the hottest heat of July. I have to water 8 hours to get an inch of water from my sprinklers. You'll have to test your system with cat food or tuna cans to see how long it takes your system. Water when the grass looks wilty, not when the soil feels dry.

Prevent weeds by infrequent watering and by mowing high. Infrequent watering (as described above) prevents weeds by not keeping the weed seeds moist enough to sprout. Mowing high prevents them by not giving them access to direct sunlight necessary for the seedlings to take root. Mowing high means not the lowest setting on the mower. I have two homes and treat them differently. The yard I mow is mowed every 2 weeks at the mower's highest setting. If you don't like grass at 5 inches high, then lower yours a notch. Don't go below 3 inches unless you have bermuda, bentgrass, zoysia, or centipede. My other yard has not been mowed at all since Sept 2011. Most spouses and communities will not let you do that, but it is working in my area. At least there are no weeds. That was part of this experiment. It is surrounded by bluestem, a prairie grass. It has invaded most of Texas but not my yard. The point of this is you are not allowed to blame your weeds on your neighbor's infestation. Even crabgrass will stop at the edge of your lawn if you mow high and water infrequently.