Ten color varieties exist -- white, cream, yellow, red, pink, purple, violet, orange, salmon, green, and a mixed category that includes vermillion, brown, black, bronze, maroon and apricot. Blue is the one color that not available in tulip bulbs. There are bulbs that have blue shading or blue coloring at the bottom of the cup, or perianth. A study was done by the Japanese Society of Plant Physiologists on tulips to determine why the lack of a blue flower. The study concluded that the key to developing a true blue tulip lay in the amount of ferric ions the bulb distributes to the perianth.
The 10 color varieties of tulips are available in every shade of red, white, cream and so forth. The tulip propagates by offsets that grow off the original bulb. However, a mosaic virus carried by aphids can attack the tulip bulb, which results in an entirely different color pattern. A red tulip bulb may bloom blood-red for a year or two, and bloom a mottled or streaked flower in subsequent years. This type of color change is referred to as a broken tulip bulb. The offsets produced by a broken bulb may contain the gene that caused the discoloration. There is a chance that the offset may produce a solid color flower. The color combinations are endless when the virus attacks the tulip bulb.
Flames and Feathers
The broken tulip bulbs have evolved so that modern cultivars carry the effects of the mosaic virus without the disease. Many different types of tulips are available that have markings similar to flames or feathers along the edges of the petals. The base color of the tulip flower is one color, such as white, and the flame or feather marking is a contrasting color, such as purple or pink.
Stem and Leaf Color
There are early-, mid-, and late-season varieties of tulip bulbs. Heights range from 4 inches to 30 inches, and the flower formation ranges from the standard cup to blooms that resemble a day lily. Certain cultivars have colored stems and leaves. For instance, foliage on the "Kaufmanniana" tulip varieties can be bluish-green or a chocolate brown. The foliage may also have stripes, such as the "Greigii" tulip varieties.