In doing some spring cleanup, I noticed something I hadn't before
dealt with on many of my TBs in one bed. Several clumps had
one or two little fans with what looked like black dust on the rhizome
and in many cases going up to virtually cover the few inches of
newly growing fan. These fans were brittle and broke off easily.
The closest diagnosis I could find in The World of Irises is botrytis,
and it wasn't very encouraging about it. It looks as if the problem
of finding space may be somewhat reduced this year here.
All alternate diagnoses or coping advice would be appreciated.
Jim Wilson, Oxford, OH, USDA Zone 6a, AIS garden judge, Region 6
growing medians, TBs, Siberians, JIs, and a few SPU and species