Bigleaf Hydrangeas (Hydrangea macrophylla) is the common garden Hydrangea that has white, pink, purple, blue or lavender blooms. However our area is great for the pink, lavender, white and pink. The Blue, as pictured to the left, is not because our local conditions.
For the bright blue color your need acidic soils which is the problem. The low annual rainfall and soils high in calcium gives the Tri-Cities alkaline soils. So Blue Hydrangeas like Nikko Blue, Blue Wave and Endless Summer a nice lavender pink. Last year Arthur and I thought we would play with our Hydrangeas in the growing operation to get them blue like the ones we ship in. What we did is what you see at the nursery right now!
This is what we did. We fed them granulated Rhody Food, similar to the Lily Miller Rhody and Evergreen Fertilizer (about a 1/4 cup per 2 feet of height or spread whichever is greater). For this product you would apply 3 times a year Easter, Memorial Day and Mid August. A substitute product would be Cotton seed Meal, or a fertilizer with Cotonseed Meal blended into it, apply 3 times but the amount may different depending on brand. Then in September we applied Aluminum Sulfate (Sulphate), at the rate of a pound per 100 sqaure feet (check the label of your brand, we used Hi-Yeild Aluminum Sulphate). After that we waited until July, to see the results, of course still feeding with the Rhody Food. We will again apply the Aluminum Sulphate in September to enjoy the blue color in 2011 on the next crop.
Well that's all for now, remember that I will be sending what's in bloom through spring and summer on our Facebook Fan Page!