SOME NOTES ON HYDRANGEAS
Big leaf hydrangea: this is Grandma’s hydrangea, the plant that is the one every one thinks of when we use the term hydrangea. It takes and needs at least 6 hours of direct sun and in most cases that can include sun that happens in the afternoon. It can get large and my recommendation is to fertilize two to three times a year and when pruning, cut only the blooms that have been spent. In order to keep it compact, prune as close to the ground as you can looking for a growth bud. When you cut back too hard the plant will not bloom until late summer. This is the plant that will bloom either blue or red, depending on how you treat the soil. You can use different chemicals to achieve strong colors.
Paniculata Hydrangea: This is the easy one. It will tolerate all kinds of sun, even in hot weather. It blooms white that turns different colors from pink to dark red. It is not effected by soil ph. Pruning is not recommended.
Oak leaf Hydrangea: These are some of the easiest plants to grow regardless of sun exposure. They are native to northern USA. They bloom all summer long and my first experience with them was as a hedge in upper New York. They bloom all summer long with white elongated blooms. In the fall they have wonderful leaf coloring. A good sturdy hedge or use in a tough location in the landscape.
Mountain Hydrangea: Known as lace cap or lace leaf hydrangea and the care is similar to the big leaf variety. The care is similar and the color is ph. controlled. Prue as you would the big leaf variety.
Smooth Leaf hydrangea: These are the hardiest of hydrangea. Since they bloom on new growth they can be pruned, if necessary, in late winter or early spring. I prefer that they not be pruned at all unless they need to be controlled.
Climbing hydrangeas: These are self-training plants that can attach to solid walls or other like types of surfaces. Slow growing and no pruning is necessary.
Regular care: Keep the soil moist and fertilize with acid fertilizer (azalea, etc. type) all will take sun exposure except in the hottest areas. 6 hours in the AM is my recommendation. They compete well with tree roots. All are deciduous and often times during the winter the leaves will mildew. This does not effect spring and summer display. Prune as recommended in order to maximize blooms.