You can propagate Nanking cherry (Prunus tomentosa) through hardwood cuttings, layering, or from seeds

Here’s a more detailed guide:

1. Hardwood Cuttings:

  • Timing: Take cuttings during the dormant season (late fall to late winter) when the plant is at rest. 
  • Selection: Choose healthy, pencil-thick branches, 6-8 inches long, with several nodes (where leaves emerge). 
  • Cutting Technique: Cut at a 45-degree angle near the base and straight across at the top for easy identification. 
  • Rooting: Plant cuttings in well-draining soil or coarse sand, burying them two-thirds deep. 
  • Environment: Maintain high humidity (a plastic dome or bag can help), keep the soil moist (not soggy), and provide a cool, but not freezing, environment. 

2. Layering:

  • Method: Bend a flexible branch to the ground, cover a portion of it with soil, and ensure it has a good contact with the soil.
  • Rooting: The buried part of the branch will develop roots, and once rooted, you can cut the branch from the parent plant and plant it as a new plant.
  • Patience: Layering can take a year or more for the branch to root and establish. 

3. Propagation from Seed:

  • Seed Collection: Collect seeds from fully ripe fruit, wash them immediately, and dry them for a few days in a shaded, well-ventilated place.
  • Cold Stratification: Seeds require a period of cold stratification (keeping them moist at low temperatures, 32 to 45 degrees F) for 100 days before germination.
  • Methods for Cold Stratification: You can do this by placing seeds in wetted sand, sphagnum-peat moss, or vermiculite and storing them in a refrigerator.
  • Planting: After cold stratification, plant the seeds outside or in pots.
  • Alternative: You can also plant seeds directly outdoors in the fall, allowing natural temperatures to achieve stratification, but moisture levels are harder to monitor.