Oh, I was also going to try to add Little Bluestem grass and wonder the same questions as above?

Thanks
:-)

i have seen some asters get out but i dont think they would be a very big problem to remove.

I have recently done the same thing on about 2/3 acre. My design came from a professional who specializes in natives and natural landscaping. All of the plants on your list are in my new yard except the Joe Pye Weed. I can't say if that is more because of its cultural requirements that hte yard did not meet or because it would not be a good choice for my goals. My goals were...native as possible, reasonably civilized so the neighbors are not appalled, habitat for birds, small mammals, encourage hummingbirds and butterflies and above all else, after the garden is established it must be virtually maintenance free. I like the idea of a garden but not hte gardening. So I have lots of groundcovers so there won't be weeding. Things like that. As to the plants he chose...in some cases they were smaller versions of the species depending on where they were going....ie Kim's Knee High rather than the species. As to Asters, he chose Aster Oblongifolius "October Skies". I think it may be a bit more restrained than some others.
Robin

Most of the plants you list will possibly spread by seed (Aster, Echinacea, Liatris) and/or by runners (Asclepias). With the exception of common milkweed (A. syriaca), none of them are invasive by my standards. They tend to fill in gaps in your planting, producing a more naturalistic look (which I like). They may encroach or overtop smaller species.

Most asters do get large and they will spread by seed if they like your conditions. Joe-pye weed can get HUGE. Both of these can be maintained at a smaller height by cutting them back by one-third to one-half early in the season. My asters are due for a haircut this weekend. This year I will experiment and let my Joe-Pye grow as tall as it wants. It is about six feet tall already and flower buds are barely visible.

I think john mo's post is an excellent example of different soil and growing conditions. In my yard, its the asters that get HUGE and get a trim, while joe pye is left to grow at his own pace, the joe pye spreads but not as quickly as the asters or culversroot.

Gee thank you all so much for all the great input.

philmont...thanks for sharing your experiences with asters. I am happy to know if they do reseed they can be pulled out easily.

Robin, that is very encouraging that your professional chose these for the goals you specified. I would have had similar goals so I was happy to hear that.
Joe....thanks for defining invasive..yes you are correct, I am more concerned with aggressiveness. I am relieved to hear that if I need to take them out, missed roots will not resprout. With the reseeding...I guess I could control the extent of the reseeding by deadheading some or most of the flowers.

John...I hadn't thought about keeping them smaller with pinching. I am hoping to try to let them grow as they like for one year but it is good to know that I could get a different result with pinching if I wanted to.

Lots of help here, thanks very much in helping me to think through how I can accomodate these great plants in my yard.

:-)

I enjoyed reading all the postings and they tend to go along with my experiences, both in my home garden and as a professional for the past 10 years. I also cut some plants in half or thirds--especially around my front door--rosin weed (for example) is very pretty and well behaved when treated this way.
The natives that I usually avoid because they are too aggressive here in Kentucky are Ratibida (grayheaded coneflower); almost all coreopsis--(one exeption--I like the tall coreopsis--true to its name is is tall, but not outwardly bound); and the grass that people call sea oats-- it spreads everywhere when given a chance. If you avoid those, the rest are slow enough in growth for you to get to know. Some people have problems with ashy sunflower, but I haven't. Good luck and have fun with your native plants--you will love the birds and butterflies you will attract!!

I have found that Cup Plant, Silphium perfoliatum, is extremely aggressive in my loamy-sandy soil. I get HUNDREDS of seedlings every spring, tough sneaky little buggers too! The Mother plant is easily three feet across and twelve feet tall at flower, and the birds go bonkers over the seed. I've tried pinching it back to shorten it and and it didn't do very well cosmetically. Although I consider this plant in the way high maintenance category, it is too magnificent not to include, just be warned.

Hi Pam and Katherine..

Thanks for your input too. I am determined to provide as much for the birds and butterflies as I can and to use as many natives as I can, but have to keep yourself on track to be able to care for it all. So it is important to know what you are in for. Pam, I couldn't give that Cup Plant that kind of maintenance so I really appreciate having that information. Although I wasn't considering using it right now, who knows, at some point I might have been. I have seen the plant and it is really a great plant.

I also have had enough experience with coreopsis to know how much of it I can contend with, and after having read a number of posts on the problems with sea oats grass, I have thankfully stayed away from that one.

Yes, I am looking forward to the birds and butterflies.
thanks :-)

Make sure you put a shallow dish with water, or better yet fill it with sand, THEN water, for the butterflies to get a drink without drowning. I also put rocks (some low, some high) in a regular ground birdbath for the smaller birds - and so no one gets trapped.

I have aromatic aster and false aster that have tripled in size in one year. Wish my butterfly weed had done that!

I'd just like to say that my garden has many of the plants you list, and they all reseed. In fact, about half of the "weeds" I get are in fact volunteers of my flowers and need clearing out. On the other hand, this gives me lots of seedlings to move around if I want, and sometimes the spots they choose are better than the ones I choose for them. One reason I enjoy gardening with native species.