acid/base indicator plants

[David W. Kramer]

>Can someone please refresh my memory about this? I have two questions?
>
>1) Is it hydrangeas that produce red or blue flowers according to soil
>pH?

 Yes, it's Hydrangea macrophylla, the "Common Bigleaf Hydrangea."  See
http://www.vg.com/vg/timelife/cg/Books/E11/Html/E11103X%2Ehtml

>2) What are the acid and base colors? My intuition is red flowers in
>acid soil, and blue in neutralor alkaline, based on other inidicator
>dyes, such as the ones (presuambly anthocyanins) in blueberries, red
>cabbage, etc.

According to the Virtual Garden (URL above), "flower color varies according
to the soil: alkaline soil produces pinkish blossoms, acid soil produces
bluish ones (white-flowered varieties are not affected by soil acidity)."

>Many thanks,
>
>Jon Greenberg
>--
>
>Jon Greenberg, Ph.D.            Curriculum Development
>Science Education Consultant    Program Evaluation
>812-330-8669			Preservice & Inservice Teacher Education
>mailto:jongreen at bluemarble.net

*********************
David W. Kramer, Ph.D.
Asst. Prof. of Evolution, Ecology, and Organismal Biology
Ohio State University at Mansfield
1680 University Drive
Mansfield, OH  44906-1547
Phone:  (419) 755-4344      FAX:  (419) 755-4367
e-mail:  kramer.8 at osu.edu