Re: Spring come to zone 4!
Great update! The R. BVT x (smirnowii x yak) and R. degronianum x roxianum Rhodie hybrids look awesome. I have Yaku Angel, which looks similar to the degronianum and have thought about trying R. roxianum and/or R. makanoi in the past.
Ever thought about sharing cuttings of the R. BVT x (smirnowii x yak) when it gets bigger? It really looks great, the leaf form and bright green color looks quite tropical... and with excellent cold hardiness too!
All things considered your I. opaca also seems to be in good shape. I've seen some Ilex opaca's at the Arnold Arboretum this spring that are nearly completely defoliated above the snow line!