In HB1043 which is the clarification bill to HB1283 passed last year they do define a difference between clones and plants.

Anything in rock-wool or similar medium that is smaller than 2"x2"x2" with the plant shorter than 8" is considered a clone and isn't counted towards the plant total.

I am not sure if this applies to private caregivers as well, but it is in the Colorado Medical Marijuana Code that will start being enforced on July 1st by the Medical Marijuana Enforcement Division.