Go for it!

Here is a link that might be useful: Propagating Perennials

Absolutely! I love the feeling of thriving abundance, and that means for the whole ecosystem. The aliens that set themselves apart from the native system are more like furniture or decor than enthusiastic, playful children hanging out with the neighborhood gang at mom earth's picnic.
~ picturing you as the Koolaid mom ;-)

If you want to see insects again, the quickest way is to stop application of pesticides.

Many so-called "exotics" attract just as much wildlife and beneficials as do native plants. Quite a few of these are merely cultivated forms of indigenous or native plants that have been developed for enhanced attributes - disease resistance may be only one of these aspects. While there are many benefits to using natives in the landscape - greater adaptability to specific locations/climates being one - native plants can also be less than ideally attractive, often appearing somewhat weedy or unkempt. In certain neighborhoods governed by HOA's or covenants, the use of only natives may be discouraged or outright prohibited.

It would probably make more sense to shoot for some sort of balance between natives and more exotic ornamentals. The exotics are not by definition considered bad or less desirable, provided one stays away from those that require excessive chemicals to maintain or that pose invasive potential. You will get the greatest benefit from any significant biodiversity in your plant selection regardless of origin and as rhodium has so astutely pointed out, avoiding all use of pesticides and other garden chemicals.

And remember, if you restrict yourself to planting ONLY natives, you can pretty much kiss off much of anything in the way of common edibles or basic kitchen garden produce.

While there are a few native plants in my area that are wonderful for a cultivated garden, most are not. Many, many of the local natives are very short-lived and very prone to rot with any kind of incidental summer watering. Exotics are faster growing, longer-lived, less prone to rot from summer watering, and still very, very xeric. Very few I've found to be invasive. For me and my situation, most natives are just not appropriate.

-Ron-

On the other hand most parts of North America supported millions of people living primarily by hunting and gathering for thousands of years before European settlement. It's true there was some growing of domesticated plants (agriculture) - corn, for instance - important to some cultures here.

Preferences of native birds can be strict, a study at the Seattle arboretum found the non-native species of trees in the same genus were being flitted through quickly on the way to native species growing or planted nearby, where more time was spent.

Those introduced species that native wildlife does respond to may often be recognized by having been dispersed by them and therefore become weeds! No advantage to that. Thrushes go for cotoneaster berries during cold spells, now we have several species rather widely naturalized - with more than 60(!) having been noted coming up wild in Seattle.

Another thing that happens is that foreign animals like rats and starlings living here feed on and disperse foreign plants.

No extreme is good. Celebrate diversity if you like, but do it responsibly.

Bt, used in mosquito to dunks, is being looked at as a possible culprit in the loss of butterflies. They are down 70%.

Please do not get discouraged:

It can be done using natives exclusive to your area and still look attractive without looking weedy - see attached picture(s)- provided you maintain them properly like any perennial border - such as edging the beds, deadheading, pruning back to control growth etc.

However, they do self-seed and increase in size much more prolifically then the exotics so you will need to take a much more rutheless approach to thinning them out.

Here is a link that might be useful:

That's really beautiful, GoNativeGal!

The book that yippee1999 references is Douglas Tallamy's Bringing Nature Home, How Native Plants Sustain Wildlife in Our Gardens.

Thoughtfully written, it includes a LOT of references to support his points. He also notes where research is lacking and apparently has some underway to fill those holes.

From Timber Press's website:

Tallamy is currently Professor and Chair of the Department of Entomology and Wildlife Ecology at the University of Delaware in Newark, Delaware, where he has written more than 65 research articles and has taught insect taxonomy, behavioral ecology, and other subjects. Chief among his research goals is to better understand the many ways insects interact with plants and how such interactions determine the diversity of animal communities.

I have mostly native plants in my garden and it is a well organized approach (I tried to use standard design principles in the areas around the house) with lots of flowering trees and shrubs. I do supplement with non-native annuals to provide more color and attract more insects.

As a result of reading Tallamy's book, I am trying to add more plants of different types rather than continue to add more of the same. As I learn more, I find there are other native plants of GA and the southeastern US that I don't have.