Shrubs for Late Summer: Panicle Hydrangea

Little Quick Fire - Photo Credits: Bailey Nurseries

It’s hot! Summer is “getting on” and we’ve seen some of our favorite plants arrive, perform, and finish their display of blooms in our landscape.  The season of Late July through September is often considered by many the “dog days” of summer.  We often think that many of our opportunities for performance in our landscape have passed us by.  Nothing could be further from the truth!  In a series of articles, we’ll share with you some of our favorite shrubs for “late summer” interest.  

Let’s talk Hydrangea.  People love them, and many are attracted to the Endless Summer series that bloom differently based on the pH of the soil.  Well, not to be a downer, but we’d best just scratch those from the list right now.  Not only do they really not tolerate our soil pH, they also do not appreciate our colder temperatures.  While there are many Hydrangea that we CANNOT grow here in our “gardens of the North” there is one Specie in particular that has become super hot among breeders.  

In this late summer scene, enter the Panicle Hydrangea!  Panicle Hydrangea, or Hydrangea paniculata - for those few of us who enjoy Latin names ;) - are enjoying an immense uptick in breeding these past years.  That might have something to do with the fact that they are cold hardy plants.  It might also have something to do with the fact that there are no soil requirements for color on these plants.  Yes, you heard me right, NO TREATING OF THE SOIL!

Limelight Hydrangea - Photo Credits: Bailey Nurseries

With the arrival of the late summer season, I often enjoy approaching these plants in my landscape and looking for evidence of developing blooms.  These Hydrangea have a panicled flower.  Something you might have guessed by their name.  These LOOSE or spacious clusters of flowers add attractive interest to the landscape in the later part of the summer.

The longevity of these flowers is nice.  When left on the plant, and the plant stays sufficiently hydrated, these blooms can last for up to or longer than, two weeks!  The color changing that these flowers go through as they mature is also attractive.  Flower panicles are built with an almost yellow color.  This color gives way to white petals, generally from the bottom of the flower and working its way up.  The white petals eventually change to a pink color.  This change occurs from bottom to top also, some like the Quick Fire tend to change their whole flower overall. While they all will likely bloom over the course of the same six-week period, some of these hydrangeas are earlier than others.  The Hydrangea show almost always begins with the Quick Fire series.  They can be the first to put on their flowers, sometimes beginning as early as the Fourth of July.  Next in line are often some of the other hybrid forms such as Bobo, Vanilla Strawberry, and others.  And perhaps the “best for last” Limelight series is usually the final performance of new blooms.

Bobo Hydrangea - Photo Credits: Bailey Nurseries

Perhaps the best additions produced by breeding are those compact varieties that make better foundation plantings.  The Bobo, and the “Little” types, Little Quick Fire and Little Lime, generally make better choices for foundation plantings since these varieties tend to mature shorter than five feet tall.

If the height is your desire, look at the parents of these hybrids.  Quickfire, Limelight, and the common Pee Gee Hydrangea can achieve heights as tall as eight or even ten feet!

Something to remember about Panicle Hydrangea is that they bloom on THIS SEASON’S growth.  Once these shrubs have leafed out, they should not be pruned or you will remove your opportunity for flowering.  The best time to do any serious pruning to Panicle Hydrangea is either after they are finished flowering, or after they have lost their leaves in the fall.

We hope you’ve enjoyed the article.  Remember, we’re always here to help!