Very well drained soil, lots of Sun and mulch under the leaves to keep them from soil contact.
This has been a bad year for it here too. 40" of rain this Spring has really taken it's toll on the Lamb's.
Lot's of mildew and lower leaf rot even w/ the mulch.
They are starting to recover though. We keep the flowers on.
We've pretty much moved to Rose Campion in most of our beds.
Far easier to grow, same basic foliage (though taller) and you don't get that center die out so no dividing.
