
Fothergilla x intermedia 'Mt. Airy' (witch alder)
Mt. Airy Fothergilla or witch alder is the gold standard for all Fothergillas. Michael Dirr selected it from Mt. Airy Arboretum 30 years ago and no other Fothergilla has appreciated like Mt. Airy - it stands the test of time.
White, 2" tall, bottlebrush-style flowers blanket Mt. Airy from top to bottom. It's covered in these cute, tiny bottlebrushes for a fairly long time - 3 to 4 weeks - in spring.
The term "kaleidoscopic fall color" is a bit hackneyed, but truthfully, I can't come up with a better term. Rather, I'll emphasize it and claim that fall color is extraordinarily kaleidoscopic.
It's unpredictably kaleidoscopic too. One year you might find red, orange, and yellow on the same shrub; other years the entire shrub might be red, orange, or yellow. More like a mood ring than a kaleidoscope? Any color, it's reliable for excellent fall color.
Thanks to Mike Dirr for the pictures.
- a woodland plant for naturalizing
- yet, I see Mt. Airy planted around retail buildings/malls, office parks, and residential settings that try for a more naturalistic plantings and in those often challenging settings (hot, sunny, bad soils), it doesn't miss a beat
- tougher than given credit
- Mt. Airy is a gentle colinizer - it's not aggressive and plays nice with its neighbors (in general, I like colonizers because they fill in areas and make that particular gardening decision for me)
- Spring: blue-green
- Summer: blue-green
- Fall: red, yellow, orange
Turns out it is a hybrid. A study published in 2007 by Dr. Tom Ranney et al at NC State found this cultivar, and many others, to be a hybrid between F. gardenii and F. major, hence F. x intermedia.