US Plant Patent PP15092
White Knight
Gladiolus plant named ‘White Knight’
PUBLIC DOMAIN
Patent expired April 24, 2022. This plant is in the public domain — anyone may propagate and sell it.
Twenty years from the filing date would end on July 31, 2021. This patent earned 267 days of term adjustment for delay at the Patent Office, which is why it runs longer.

The record
- Patent number
- PP15092
- Filed
- July 31, 2001
- Granted
- August 24, 2004
- Expires
- April 24, 2022
- Inventor
- ZIPPERER III JOHN O
Abstract
A new and distinct gladiolus variety, designated ‘White Knight’, is shown and described. The variety has a light green color (Yellow Green Group 145D) deep within the throat, followed by a pure white color throughout the rest of the petals (White Group 155D). The variety can maintain six to seven florets in open bloom simultaneously in a vase of water and is an excellent opener after transport.
Show the legal claimThe single numbered claim as granted — the legal text that defines what this patent covers.
I claim: 1. A new and distinct gladiolus variety of plant, ‘White Knight’, as shown and described herein.
Read the full patent: US Plant Patent PP15092 in full — the complete specification, every figure, and the file history.