Gardening With Native Plants

Here are some nurseries where I've found native plants:

• Herbeins - 4301 Chestnut St, Emmaus
• Tall Timbers - 4187 Huckleberry Road, Allentown
• Tilley's - 111 E Fairmount St, Coopersburg
• Tree Authority  - LLC 602 Minsi Trail, Perkasie - very reasonable prices for small to mid-sized trees

Nurseries specializing in native plants:

• Edge of the Woods - 2415 PA-100, Orefield
• Northeast Native Perennials -  1716 E Saw Mill Rd, Quakertown
• Kind Earth Growers  2503 Mountain View Drive · Ottsville, (mostly wholesale)
• Unitarian Church in Bethlehem has a spring and fall native plant sale

Other sources of native plants

https://www.dcnr.pa.gov/Conservation/WildPlants/LandscapingwithNativePlants/BuyNativePlants/Pages/default.aspx

Interesting article by Dr. Doug Tallamy

A professor of entomology at the University of Delaware, Prof. Tallamy is a source of insight and inspiration. I can recommend his talks that you can find on YouTube, as well as his books.
https://www.washingtonpost.com/outlook/welcome-bugs-into-your-yard-you-might-just-save-the-world/2020/02/20/62b0a12c-4d18-11ea-b721-9f4cdc90bc1c_story.html