The Royal Horticultural Society has iris on trial every year. Each
trial is for three years, and judging is done by the Joint Iris
Committee which includes nursery owners, breeders and iris society
members.
Here is part of the report on one of the sibirica trials, which
included sibtosas:
There were 66 entries in this long-term trial of Iris sibirica, 37 of
which were included in the display of
previous Award of Garden Merit (AGM) winners; as such they were not
judged but used as a standard
for comparison. The trial was assessed by the Joint Iris Committee
over 3 years. Assessment was
based on the following point system: Plant 35%, Stem 15%, Flower 30%
(form=10, substance=10, colour=10), Presentation 20%
Results are published. Here is a booklet on various sized bearded
iris, with pictures and descriptions. Quite a few seem to be
rebloomers. The booklet also describes how they manage the plants in
the trial. For instance, they remove dead or diseased foliage but
don't cut back good leaves.
http://www.rhs.org.uk/Plants/RHS-Publications/Plant-bulletins/Bearded-Iris-Bulletin
current trials:
Iris - Median Bearded 2010-2012
Iris sibirica 2010-2011
Iris ensata 2010-2011
Iris Pacific Coast 2010-2011
There have been many spuria trials, but none this year.
Diane
