Mary, when I google "tissue culture", this explanation comes up:
"Tissue culture is a process that involves exposing plant tissue to a specific regimen of nutrients, hormones, and light under sterile, in vitro conditions to produce many new plants, each a clone of the original mother plant, over a very short period of time."
When I bought the Cora Louise, there were 2 very small tubers, about 1" width and about 4" long the bag. I planted them 1 in ground and 1 in pot and it took them 2 growing seasons to reach blooming size. I bought a Lollipop itoh from Michigan Bulb last year which I believe is also tissue cultured. THis itoh is probably smaller than the Cora Louise. I think it is going to take me 4 years to see a bloom from it.