Hi Gang, Flower colors are endlessly variable. When color, shape and size are considered together the variation goes on forever and that is part of the reason flowers are so special. One recent article explores the reason for blue petal bases in Tulipa gesneriana cv. Murasakizuisho. The flower is mostly purple, but the bases of the tepals are blue. The scientists ground up the various parts of the tepals and analyzed them. The found that the extracts from purple regions and blue regions were essentially identical with a single exception; the blue regions had higher concentrations of iron. The blue-colored cells had about 25-fold more iron than the purple-colored cells. Tulips are clever. Somehow they know to concentrate iron in specific cells of the perianth, or perhaps to deplete iron from other cells. Additionally, ferrous iron (Fe3+) is employed for the effect, not ferric iron (Fe2+). I've always known that tulips are among the more intelligent of plants and think that this news reinforces that idea. LINK: (Abstract) Perianth Bottom-Specific Blue Color Development in Tulip cv. Murasakizuisho Requires Ferric Ions http://pcp.oxfordjournals.org/cgi/content/… Cordially, Joe Conroe TX Rain is forecast, rainlilies are blooming, a green heron has adopted my garden (the low part) as its own. The frogs, mosquito fish, and small snakes are a bonanza this spring; in 2 months the wet area will likely be dry.