What Happened to my Hydrangeas?

Posted on: May 20, 2014

Here is an interesting article by Nancy DuBrule on why some of you Marylanders may be having Hydrangea heartache. Email KW Landscaping if you would like their professional opinion and help recovering your hydrandeas.

Hydrangea after a harsh winter
Hydrangea after a harsh winter


What Happened to my Hydrangeas?? 

I have been talking to customers non-stop about their hydrangea plants. All of the Hydrangea macrophylla varieties basically look like the picture above. Do yours? What happened and what can you do about it?
Hydrangea macrophylla are also called the mophead or old fashioned pink/blue hydrangeas. They are classic summer flowers beloved by all gardeners. Until a few years ago, the most common variety was ‘Nikko Blue’ although there were many other varieties out there. They all shared the same characteristic- the flowers appeared as new shoots off of last years wood. We call that “old wood”. The wood on the old fashioned types was hardy only to zone 6. If it got to 10 degrees below zero or colder, it would freeze and die. This winter, we went below that for an extended period of time. I am not surprised to see that all of the old wood on these hydrangeas now look like “dead sticks”.

On our crews and in our own gardens, we have waited for over a month for these “sticks” to sprout green growth. Now that we are in the middle of May and the weather is finally warming up, we have determined that if there isn’t any new growth emerging on last year’s wood, the “sticks” are dead and need to be cut down.

Coming up from the base of the plants are lots of fresh green shoots. Hooray! The plants are alive! Does this mean they are going to still flower this year? Not necessarily. The older varieties will not bloom off of new wood. You will have a big, lush, green plant but no flowers this year.

Enter Hydrangea macrophylla ‘Endless Summer’, a plant introduced a few years ago. This was a breakthrough in breeding as this plant blooms on old wood AND new wood. Most of of new cultivars are repeat blooming on new wood. This includes the fabulous new ‘Bloomstruck’, an improved ‘Endless Summer’ with bigger, more brilliant blue flowers. Varieties that bloom on new wood and will flower even after a severely cold winter include:

  • ‘Bloomstruck’
  • ‘Everlasting Garnet’
  • ‘Everlasting Ocean’
  • ‘Everlasting Revolution’
  • ‘Pistachio’
  • Endless Summer ‘Blushing Bride’
  • Endless Summer ‘Twist and Shout’

You may want to consider ripping out your old varieties that are so much trouble to care for and replace them with new, modern hybrids. If that is impractical, then you should wrap them every winter to protect them from extremely cold temperatures.

Maryland Hydrangeas Garden
Maryland hydrangeas garden