I have 3 of the halo series (Angel Eyes and Angel Robe) in a shady location with dappled sun. One of the three plants is doing quite well and growing in size each year. The other two are about the same as when I bought them in 2006 and look like they need some kind of change.
When I bought them, they were advertised as shade-loving hydrangeas, but I'm beginning to wonder. They are beautiful, though!
Does anyone know how much sun and what kind of care these hydrangeas need?
Anyone growing Halo Hydrangeas?
The trouble with hydrangeas and shade is that often that shade comes in the form of a tree whose roots compete with the thirsty hydrangeas for moisture. I've always had the best luck with my hydrangeas if I can find an area that's shady but not under a tree, otherwise they tend to struggle along. If you need to move them, morning sun is typically fine for them, but I would make sure they're in shade during the afternoon when the sun is hotter.
Halos should use the standard measurement for part shade plants. This equates to 4 hours or less. Here in Texas where the sun is very strong in the summer, I have to provide shade to other hydrangea varieties starting at 11am or so; this is less than 4 hours of sun. The amount of sun (4 hrs) should be measured during the hot summer months in order to determine if the plant leaves suffer from sunburn then. Thus, four hours of sun during winter may be fine but you may also discover that the plant leaves suffer during the summer. Signs of sunburn or sun bleach are leaves that turn all yellow (including the leaf veins) or turn a shade of white. Sunburned leaves eventually fall off. Consider transplanting to a shadier location if this occurs. And keep in mind the eventual mature size (height x width at 10 years) of the plant when selecting the planting location. Halos are around 3x3 feet at maturity, except for Frau Reiko and Taiko who can get to 5'. If the sun will come at an angle, the first 3' may be in shade but the top 2' may be too long under sunlight. This is a problem that I am having with hydrangeas planted by the previous owner of the house. I now prune the plants to maintain a certain height that will not cause sunburn. But I admit it is a hassle.
Most variegated *leaf* plants require a little less sun than their un-variegated (?) cousins. It should be interesting to see if these variegated *bloom* plants require the same too (note: there are no instructions to do that from the wholesaler but then again, they do not address the subject... they just recommend part shade to full shade). H. Macrophylla Harlequin does not require that either.