On Jun 28, 2011, teamcrawford from Bristow, VA wrote:
I hired a landscape architect who is a certified botanist to design a master plan for my landscaping. I love hydrandeas and specified blue. Phase 1 included planting three Nikko Blues. Right off the bat there was trouble. First, the blooms were pink when they arrived in the containers. I asked the landscaper about this and he said they start out pink and then turn blue. Well, I've scoured the internet and have not seen anything that confirms this. They are blooming profusely--in pink!
Second problem--within less than a week all three developed unsightly rusty blemishes on the leaves. The leaves are covered in them, as well as the new-growth stalks. Not one leave is left unscathed. I am hearsick! Landscaper says it's just shock, but I'm convinced they were diseased in the containers. They are looking worse and worse as each week passes.
Contrast those to the hydrangea we planted a few years ago, purchased at the grocery store. It's thriving, with beautiful big blue blooms with really no care at all. I don't know what kind of hydrangea it is, but it truly outshines the so-called Nikko Blues.
Has anyone ever heard of these starting out pink and then turning blue? I don't know what to do about the unsightly rust stains except collect the fallen leaves and dispose of them as was recommended. Any advice? I am in zone 7A. Thanks!
BTW, no recourse through the landscaper--he retired out of state :(
Just like other Hydrangea macrophylla cultivars, Nikko Blue's color is pH sensitive--it'll be blue only if you have acidic soil, but if the soil is alkaline then it'll be pink. Since your other hydrangeas are blue without you doing anything, I suspect your soil is acidic so over time they will turn blue, and next year they'll be blue right from the start. The pink you're seeing now is due to the conditions in the container they were growing in before you got them (either the container soil was alkaline or it was deficient in aluminum). It will take a little time for the pH of your soil to kick in and turn them blue though, it doesn't happen overnight.
As far as the spots--they are not rust. I've found hydrangeas can be prone to that sort of spotting if you do a lot of overhead watering, particularly in the evening. To avoid them in the future, water in the morning and try to be careful that water's not splashing back up onto the leaves when you water. Spots like that may be ugly but they're not typically fatal so I wouldn't panic about them.
But I would dispose of the leaves in the trash as soon as they dry out in the Fall. They are indications of a fungal infection and it would be best to get rid of the leaves & their spores in the trash as opposed to say, the compost pile.
This is what rust look like, courtesy of the national arboretum: