Others on this forum have more experience specific to prairies but this is what has done o.k. for me:
Spray Round up again. Plant a thick cover crop of rye grain in the fall. Cut the rye grain down a week or two before you want to add seed (and always before the rye grain goes to seed), or add the seed in the fall just after the rye grain starts to grow and the winter will scarify the seeds for you, etc. The rye grain helps to hold your soil together and helps suppress weeds. Make sure you cut down the rye grain before it goes to seed.

You'll never be completely free of dandelions, so I don't think you need to delay past next spring because of dandelions. You probably still have quack grass seed in the ground, but much of what is left should sprout next spring, at which time you can kill the seedlings and plant. After that, you'll have to hand-pull or spot-spray quack grass. This will require the ability to identify quack grass versus the native grasses you plant to plant. So, I think if the quack grass isn't too thick in the spring, and if you think you can identify it, then I'd go ahead and plant in the spring.

If you have an area of thin lawn on relatively infertile soil all you need to do is use Round Up in spots throughout your lawn. Wait about 48 hours or until grass and weeds die where you sprayed. Then plant perenials all over your lawn, any kind you like. Remember you are not creating an extended border. This is your wild garden. Also plant lots of spring bulbs in late fall. Buy them on clearance sales, and buy lots of bulbs. You do not need to seed wildflowers. Too expensive and takes too much work and time. Do not think of your area as ground cover. Just let your perenials and bulbs spread and multiply and leave your native or non-native grass to grow. Kill any wild tree volunteers by digging out or carefully kill them with Round Up. Plant a few fruit ar flowering trees in your wild garden/meadow. Relax. By the way. Round Up has no effect on your garden soil. Once it dries on plant it will harm no one, man or beast.

zucker
tell me more. i am afraid to use chemicals. is roundup really so safe>? also i love the idea of roundup in spot treatments and once the area dies put in plants or bulbs. i do have dallisgrass i want to get rid of and the "lawn" is more of a meadow with definite thin dry areas i think would be ideal for wildflowers as many do pop up in the yard, which i love.
please elaborate, i've never heard this idea before and i've been gardening about 25 yrs.

I don't think spot treating is going to give one an attractive wildflower meadow. Its going to look clumpy - IMPO. And most bulbs are not native, not sure if that is important to your planting or not.

Round up is not as safe as claimed above. IT can hurt animals, particularly fish and amphibians, when not used correctly. I do think roundup is safer than most other herbicide alternatives, but it needs to be used wisely and in accordance with directions.

If you are starting with lawn, I would either smother it with newspapers and mulch and plant the area in plugs. Or I would kill the area with round up, wait a few weeks, mow the dead turf off and then overseed the area with a quality wildflower mixture, right into the dead turf.

You can get quality seed mixtures from places like Prairie Nursery, Prairie Moon Nursery and Ion Exchange. Those are US sources, you may be able to find a Canadian equivalent.

The Prairie Nursery website contains some good instructions on how to prepare a site. I would suggest you read that also.

the last post gave some great sources of info and you should avail yourself of their knowledge. from my experience i will say this; good site prep is absolutely essential. without it, you'll fight weeds forever and make this project (natural prairie resoration is difficult!) even harder. i don't like herbicides, but sometimes that's the only solution short of low yield nuclear weapons.

Thanks everyone for all your help! Well, I think I'm ready for seeding (I hope). Last spring, I mowed, tilled and then applied round up in the summer and once in the fall. This spring, I'll wait for the weeds to come up with the spring rain, round up one last time and seed.

I've got Idaho and Rough Fescue, June grass, Western and Northern Wheatgrass mixed 50/50 with my wildflower seed. Getting very excited after all this site preparation to plant this year. I also bought some annual wildflowers to border the meadow with some colour this year.

Thanks again for all your help. I'll post some pictures when this meadow looks its best (In two or three years...lol)

louisianagal ~

You may want to search for a mail order nursery that specializes in Deep South or or Gulf Coast varieties. Prairie Nursery, that is frequently recommended on this site, specifically says that they only recommend they products for zones 1&2, and you and I are definitely out, being in their zone 3.

Spring Hill Nursery works only with Texas varieties. You could possibly benefit from their Region 5 "East Texas" recommendations.

Here is a link that might be useful: Spring Hill Nursery

Thanks for all your lovely advice everyone. The meadow got seeded this year. All that site prep seems to have paid off so far, not too many weeds to contend with, lots of little perennial seedlings popping up and the annual wild sunflower put on a nice show for the first year. Unfortunately an early frost killed off all those sunflowers before they could go to seed, but the perennials still look good. Next year the big show should start!

Sunflowers are all gone now...frost killed them before they had a chance to go to seed:( Oh well! Really excited as I did the last round of weed trimming though. This is the meadows first year, but it looks like my clump grasses got a good foothold and I already have a little brown-eyed susans, grey headed coneflowers and blue flax that flowered this year! So exciting to see them already. I can't wait until next year to see it really take off. Will keep you all posted with pictures next year. Thanks for all your advice!

Just an update. I'm including some updated pictures of the meadow from groundbreaking to current time (in it's second year). It's really doing well! I love waking up and looking out at it!

Raking after an entire season of round up application:

All seeded and ready to water:

First Growth:

Native Annual Sunflower fall of 2008:

And finally some perennials coming up this year:

DId your local seed provider tell you to mow the first couple of years? IF you mow your planted area in June you will mow off whatever weeds have come up as they will be fairly tall by then but the natives will not have come up yet so you won't cut them off. You are preventing the weeds from going to seed and eventually they will die out as the prairie you planted takes hold. Although now that I think about it your in zone 2 so maybe mowing in june isn't accurate.....you'd have to ask them when mowing would be appropriate for your area. btw..beautiful dog!!

Yes my seed provider did tell me to mow the first few years. I've been taking a weedwhacker out there this year to selectively trim the weeds as they go to seed. It really has helped a lot. There were many annual weeds last year that have already been crowded out by the natives this year! So exciting! Oh and Hanna the german shepherd thanks you! We think she's beautiful too!

I bought wildflower seeds from Eden Brothers this spring and the annuals are doing great. I'll report back later on the perennials. They also have very succinct planting instructions about how to grow wildflowers.

Here is a link that might be useful: Eden Brothers