How to Grow Smoke Bush Cotinus From Seeds

Cotinus coggygria goes by several common names, including smoke bush, smoke tree and fustet. The common name smoke bush refers to the airy appearance of the pale purple flowers, which strongly resemble wood smoke when in full bloom. It adds a striking visual element to gardens both with its flowers and its purplish foliage, which turn shades of yellow, pink and orange in autumn. Unlike many species of ornamental shrub, smoke bush grows true from seeds, even if the seeds are old. However, they require a lengthy period of warm and cold stratification to successfully germinate.

4-inch plastic pots
Potting soil
Perlite
Medium-grit sand
Plastic wrap

Instructions

- 1
  Prepare a pot for each smoke bush you want to grow. Fill 4-inch plastic pots with a mixture of 5-parts potting soil and 1-part perlite or vermiculite. Fill the pot to within an inch of the top. Pour water into each pot until the top half of the soil mixture is wet.
- 2
  Sow two smoke bush seeds in each pot of soil. Press the seeds onto the surface of the soil mixture. Cover the seeds with a 1/4-inch-thick layer of potting soil. Firm the soil. Sprinkle medium-grit sand across the surface of the soil to insulate it and help hold in moisture.
- 3
  Cover the pots in plastic wrap. Set the pots outdoors under dappled shade where temperatures stay around 60 F during the day. Keep them under these conditions for 75 days. Remove the plastic and remoisten the soil periodically during the warm stratification period so it never fully dries out.
- 4
  Move the pots into a refrigerator for 75 days to cold-stratify the seeds. Remove the plastic and remoisten the soil mixture whenever it dries out. Put the plastic back in place after watering.
- 5
  Remove the plastic after the cold stratification period. Set the pots on a bright, sunny windowsill where temperatures stay above 60 F during the day. Keep the soil barely moist as it warms to avoid fungal growth on the surface.
- 6
  Watch for germination starting in four months but do not be discouraged if it takes up to one year for the seeds to germinate. Remove the weaker or less vigorous of the two smoke bush seedlings from each pot, if both seeds happen to germinate.
- 7
  Move the pots outdoors in spring once daytime temperatures reach 60 F. Keep the seedlings in a sheltered spot away from direct sun for the first few weeks, and then slowly acclimate them to stronger light until they can stand in the sun for five to six hours without wilting.
- 8
  Keep the smoke bushes in their pots for one year. Transplant them into 12-inch nursery containers once they reach 5 inches in height. Keep them in their nursery containers inside a cold frame for one year. Transplant them into a permanent bed the next spring.

Brown Spots on a Potted Shrub

How to Trim Oleanders in the Southwest

Shrubs