What is the best ph to have healthy hydrangias?

Asked March 18, 2017, 12:02 PM EDT

I have been growing climbing hydrangias that have white blossems on an arbor for about 18 years. They are very big now and they do bloom nearly every year but I wanted to be sure that they are healthy and to get a few more blossoms so I had the soil tested by a lab. The ph is 4.9. I have a table that says blue hydrangias should have a ph of 4.0 - 5.0, pink hydrangias 6.0 - 7.0, and white hydrangias 6.5 - 8.0. What ph should I have to make sure that my plants are healthy and bloom a little more?

Charles County Maryland hydrangeas climbing hydrangeas

1 Response

In many of the reference books, there are no specifics on pH for this climbing vine, Hydrangea anomala petiolaris. In general, Climbing hydrangeas are noted for starting slowly but once its roots are established it grows rapidly. It prefers soil that is slightly acid, rich in organic matter and moist but not soggy.
It is best not to mess with success. Your vine sounds happy. You can apply a layer of compost around the base of the plant each spring. Do not overfertilize as too much nitrogen will promote green growth at the expense of flowering.
The other hydrangeas you mention are shrubs not vines. If you have other types of hydrangeas Ph is about 6-8. It may be easiest to enjoy the natural color your hydrangea offers
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