Genus
Vernonia
4 US plant patents have been granted in this genus. 0 are already in the public domain — anyone may propagate and sell them. The next of the 4 still protected comes off patent on March 31, 2036.
Still under patent — 4 cultivars
Soonest to come off patent first. You may not propagate these for sale until the date shown.
- Summer's SurrenderPP28475Vernonia plant named ‘Summer's Surrender’UNDER PATENTMarch 31, 2036
- Summer's Swan SongPP28556Vernonia plant named ‘Summer's Swan Song’UNDER PATENTApril 5, 2036
- Summer's EndPP33602Vernonia plant named ‘Summer's End’UNDER PATENTDecember 23, 2040
- Prairie PrincessPP36918Vernonia plant named ‘Prairie Princess’UNDER PATENTJuly 25, 2044
A patent expiring frees the plant, and its cultivar name comes with it — cultivar names cannot be trademarked, so they are always free to use. What it does not free is any brand name the plant is marketed under. Those are trademarks and renew indefinitely.