Bush Daisy (Dimorphotheca ecklonis) 2016-6-4 Newark, DE

aka White Daisy Bush, Blue and White Daisy Bush, African Daisy, Cape Marguerite, Van Staden's River Daisy, Sundays River Daisy

I've never seen a flower so pure white. When the sun shines directly on it and you look at it a while, it's almost like going snow blind. Only when the flower gets old does it get a slight pink tinge at the tips of the petals.

-according to Tropicos at
http://www.tropicos.org/Name/2721750
the genus name is Osteospermum

-plants.usda.gov shows "Osteospermum ecklonis (DC.) Norl. blue and white daisybush" as introduced and naturalized in California
http://plants.usda.gov/core/profile?symbol=OSEC
-and the Jepson Interchange:
http://ucjeps.berkeley.edu/cgi-bin/get_cpn.pl?OSEC
lists the California sp. current name as: Dimorphotheca ecklonis DC
and the map there shows naturalization along the southern coast of California
-and a picture from calphotos.berkeley:
http://calphotos.berkeley.edu/cgi/img_query?enlarge=0000+0000+0412+0932
where you can see the pink tipped petals on the, mostly, older flowers on this bush that obviously hasn't been dead-headed

more info from plantzafrica.com
-D. ecklonis
http://www.plantzafrica.com/plantcd/dimorphecklon.htm
"D. ecklonis has beautiful, white ray florets and a dark blue centre (disc florets)" - also, description, distribution, habitat, etc.
http://www.plantzafrica.com/plantcd/dimorthothecapluvialis.htm
-D. pluvialis
http://www.plantzafrica.com/plantcd/dimorthothecapluvialis.htm
2 varietes:
white with yellow center
and
deep violet ring on the petals around the yellow center
-D. sinuata
http://www.plantzafrica.com/plantcd/dimorphsinuata.htm
orange with orange center, sometimes yellow center
-D. jucunda
http://www.plantzafrica.com/plantcd/dimorphjuc.htm
"The ray florets are magenta-pink or purple above, orange or coppery below. The disc florets are dark purple or yellow tipped blackish."