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US Plant Patent PP18341

HYMMAD III

Hydrangea macrophylla plant named ‘HYMMAD III’

PUBLIC DOMAIN

Patent expired May 15, 2026. This plant is in the public domain — anyone may propagate and sell it.

Twenty years from the filing date would end on February 6, 2026. This patent earned 98 days of term adjustment for delay at the Patent Office, which is why it runs longer.

Figure 1 of US plant patent PP18341, the photograph of HYMMAD III printed in the patent.
Figure 1 from US Plant Patent PP18341, reproduced as printed. Photographs in a plant patent are taken by the applicant. Reproduction of the patent document is permitted; the image is shown whole and uncropped for that reason.

The record

Patent number
PP18341
Filed
February 6, 2006
Granted
December 25, 2007
Expires
May 15, 2026
Assignee
UNIV GEORGIA RES FOUND
Inventor
DIRR MICHAEL A

Abstract

Hydrangea macrophylla, ‘HYMMAD III’ has large, pure white lacecap inflorescences that respond slightly with maturation to the absence and presence of aluminum becoming pink or blue, respectively. The habit is upright and strong stems that hold the inflorescences erect. The large, lustrous, dark green leaves are highly mildew and Cercospora resistant, as well as frost resistant.

Show the legal claimThe single numbered claim as granted — the legal text that defines what this patent covers.

1. A new and distinct variety of Hydrangea macrophylla plant substantially as herein described and illustrated.

Read the full patent: US Plant Patent PP18341 in full — the complete specification, every figure, and the file history.