|MadSci Network: Botany|
I have never heard that a change in soil chemistry can affect tulip flower color. Soil pH can affect the color of hydrangea flowers. Hydrangea flowers are blue when the soil pH is acid and pink when the pH is neutral or alkaline. With an acid soil pH, aluminum is more soluble and absorbed by the hydrangea. The aluminum alters the flower pigment. All sorts of fruits, leaves and flowers, icluding poppy and tulips, may change color when exposed to acids or bases because of the anthocyanins they contain. These sorts of plant pH indicators are often used in science classes, particularly red or purple cabbage leaves. Many white cut flowers, such as chrysanthemum, daisy, carnation, and wild carrot, can be dyed by placing the cut stem in a dye, such as food coloring, and allowing the dye to move up the xylem into the flower petals. White tulips could probably be dyed other colors with this technique but usually do not need to be dyed because tulips come in a wide color range. Tulips infected with certain viruses change flower coloration. The infected tulips have flowers with uneven color patterns and are known as Rembrandt or broken tulips. The Rembrandt tulips sparked the rampant speculation in tulips during the 1630s in Holland known as Tulipomania. When the tulip market crashed, many were left in financial ruin. References Hydrangea Color Change MadSci Experiments: Coloring Plant Transpiration What household substances can be used as acid/base indicators? Dyeing cut flowers: http://www.allsands.com/Gardening/dyingcutflower_vrz_gn.htm (link defunct 8/23/2006) Replaced with: Dye Summary Tulip breaking potyvirus Tulipomania MadSci FAQs: Anthocyanins
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