May 2013

Readers ask about Jerusalem artichokes, jet bead and color changing tulips

Winter hardy sunchokes are related to sunflowers and are native in to the Eastern United States. © CanStockPhoto Inc./Jochen

Questions about tulips, jet bead and Jerusalem artichokes fill the inbox.

M.S. of Indianapolis wants to know “why do some tulips in the landscape change color?”

Several things could cause this. Some tulip bulbs are bred to do change colors through the day. Other times, it could be the natural aging of the flowers, when many colors fade.

“While not common, it occasionally happens that a bulb flower’s bloom color can change through a spontaneous mutation or exposure to natural elements that cause one layer of cells to mutate to another color,” said Tim Schipper, owner of “The bulb itself is unaffected and remains healthy, but the flower color is different.”

Invasive species

D.O. read about jet bead, a shrub noted for thriving in “bad soil, shade and slopes. I thought I hit the jackpot. However, after doing some research, I find that it’s a very invasive shrub. Is this true?”

Jet bead (Rhodotypos scandens) does sound like a dream plant because it survives in less than desirable growing conditions. Its over-adapatability and proliferation is why this Asian shrub is considered a pest.

“Jet bead is a serious problem in Indy Parks, and a few other natural areas in the state,” said Ellen Jacquart, director of northern stewardship at the Nature Conservancy of Indiana and a member of the Indiana Invasive Plant Committee. “This is one we’d really like to get assessed and out of trade.”


P.B. “is interested in planting Jerusalem artichoke, but am having trouble finding any bulbs. Any suggestions?”

Jerusalem artichoke (Helianthus tuberosus), frequently called sunchoke, is a perennial in central Indiana, usually planted from edible tubers. It is related to the sunflower, but not to artichoke (Cynara cardunculus var. scolymus), which can be grown from seed as an annual in cold climates. Each of these will likely have to be ordered from online retailers. Jung Seed sells both. Purdue University has more info on growing sunchokes.