“What does it mean that this plant is patented? I’m not allowed to propagate it?”
That’s what it means. You are not allowed to propagate it.
Here’s the typical legal boilerplate:
“Asexual propagation of patented plants (including any of its parts such as leaves, buds, cuttings, seeds, fruit or pollen) is strictly prohibited without the written authorization of the patent holder or the patent holder’s agent.”
For many years, the only plants commonly patented in the nursery industry were roses. The company that introduced a new variety held the patent and either kept it as an exclusive product or licensed it to other growers to grow for a fee. Patented roses cost a couple more dollars than older ones did. After the patent expired in 20 years, anybody could propagate and sell the rose without paying a patent fee to the originator.
To read the rest of the story, please go to: Davis Enterprise