Answer: To be honest I am not sure exactly which plant you found at the florist's, but here are some possibilities. Genista tinctoria (Common Woadwaxen or Dyer's Greenwood) is a small shrub hardy to zone 4, and it does well in a hot sunny spot with well drained even sandy soil, preferably neutral to alkaline in pH. There is another plant sometimes called "Lydia Broom" which is similar. It is also a Genista (Genista lydia) but it is only hardy to zone 7. There are also a number of actual brooms (Cytisus) which could look similar but they are not hardy in areas as cold as yours.
Burpee does not offer these, but if you can offer the soil conditions it needs and a sheltered spot, you might try one of the genistas available from specialty nurseries such as Carroll Gardens (800-638-6334) 444 East Main St., PO Box 310, Westminster, MD 21157.
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