US Plant Patent PP28469
Plumsweet XVIII
Plum tree named ‘Plumsweet XVIII’
UNDER PATENT
Still under patent. Protection ends January 17, 2036.
Twenty years from the filing date would end on December 11, 2035. This patent earned 37 days of term adjustment for delay at the Patent Office, which is why it runs longer.

The record
- Patent number
- PP28469
- Filed
- December 11, 2015
- Granted
- October 3, 2017
- Expires
- January 17, 2036
- Assignee
- BRADFORD LOWELL GLEN, QUISENBERRY JON M
- Inventor
- BRADFORD LOWELL GLEN; QUISENBERRY JON M
Abstract
The present invention relates to a plum tree and more particularly to a new and distinct variety broadly characterized by a large size, vigorous, hardy, and productive tree. Being self-unfruitful, the present variety requires cross pollination from an apricot, interspecific, or plum that blooms during the mid season, such as ‘September Yummy’ plum (U.S. Plant Pat. No. 14,220). The present variety's abundance of blossoms and moderate pollen production entices strong bee activity to facilitate pollination. The fruit matures under the ecological conditions described during late June, with first picking on Jun. 29, 2015, and will hang on the tree for at least fifteen more days. The fruit is uniformly large in size, yellow with heavy red dappling skin color, clingstone in type, heart shaped, full red in flesh color, very firm and crisp in texture, and very good in flavor.
Show the legal claimThe single numbered claim as granted — the legal text that defines what this patent covers.
We claim: 1. A new and distinct variety of plum tree, Prunus salicina , substantially as illustrated and described, that is most similar to ‘Plumsweet XIV’ (U.S. Plant Pat. No. 23,686) interspecific tree by blooming in the mid season, by being self-unfruitful, and by producing fruit that is clingstone in type, that is sweet, that is firm, that is juicy, that is very good in flavor, and that ripens in the mid season, but is distinguished therefrom by having a larger tree and by producing fruit that is oblong to heart shaped instead of globose, that has much stronger red dappling on the skin, and that is much larger in size.
Read the full patent: US Plant Patent PP28469 in full — the complete specification, every figure, and the file history.