Caribou Trail along with its sibling Butterscotch Kiss were very popular in the late 1950's and early 60's, but by today's standards they would be discarded in a seedling patch. For us old timers I would love to have them in my garden now, but they are not available through commercial nuseries,
Notes on Faithful and True in my experience:
~Very vigorous, 15 rhizomes out of one initial start in 2018.
~8-10 buds on a rebloom stalk averaged.
~Zone 7a dependable rebloom, four reblooms as of 2022.
~Has NOT spring bloomed for me.
~Strong and sturdy rebloom stalks
Highly recommend this iris for its reliable rebloom and vigorous growth. To boot, a very pretty sight.
I have found 'Saffron Drift' to be a strong grower, although intriguingly it seems that its offspring can be more vigorous than it!
I have used it in a couple of crosses as a pod parent, as unfortunately it never produces pollen for me (a trait that seems to be consistently inherited by its progeny as well). The other trait I have observed appear in most of its offspring is strong veining on the hafts/shoulders.
In my opinion, 'Frostfall' is probably best suited to being a cut flower. It has a high bud count but very short branches, so all the blooms are held close to the stem (somewhat reminiscent of gladioli). The bloom stem is quite sturdy as well and is more likely to blow over in wild weather than to break. The flower form is pleasing and resistant to collapse under light to moderate rainfall.
Despite looking like a white self, 'Laced Cotton' is actually a plicata with most of the anthocyanin suppressed. Keith Keppel has verified that it is a plicata and the existence of plicata offspring such as Tall Bearded Iris (Iris 'Rhonda Fleming') proves that it must carry at least 50% plicata genes (since the plicata group are recessive).
Although this is classified as an Intermediate, it is marketed in Australia mostly as a Standard Dwarf and is comparable to other SDBs in my garden. I can only assume that it requires certain conditions to reach its registered height.