"Why Isn't My Hydrangea Blooming?"
Updated: Sep 7, 2021
It doesn't matter where I am around town, at a restaurant, at church, at the gas station, or even at Lowes garden department, once folks find out what I do for a living, the conversation turns to gardening and landscaping.
The most often asked question is always a variation of the following, "Why isn’t my hydrangea blooming?” “I did everything, I trimmed it, (uh-oh), I watered it, I put that stuff on it to make it bluer”, And you know, I can tell these folks are kind of sad about it so I nod my head and empathize, and then it happens. “What did I do wrong? I loved that hydrangea, it was my mother’s and I haven't seen a bloom for many years.”
I always start with the short answer in these situations and that is that most hydrangeas need two things, afternoon shade and lots of water. And then invariably, my new acquaintance admits her hydrangea is in full sun and she never waters. Ahhh yes. Is that bad?” Well you tell me, how is the hydrangea doing? “Ummmmmm”. Big blank stare. She just doesn’t know. Let's just stop and take a breath, I am going to take a moment to take the mystery out of hydrangeas. The trimming, the blooming or should I say, the lack of blooming.
Simply put, there are about 5 different kinds of hydrangeas growing in our region. Several bloom on new green stems, those are easy. Two grow on last years wood. Let's start with the native ones.
The widely accepted definition of "native" plants are those plants that are indigenous to a given region or ecosystem. A plant is considered native if its presence in that region is the result of only natural processes, with no human intervention to a given area in geologic time. This includes plants that have developed, occur naturally, or existed for many years in an area.
Hydrangea Quercifolia ( Oakleaf Hydrangeas) are known for their big beautiful, football size blossoms and large leaves that look a bit like the leaves on an oak tree. Here’s the important information about blooming, Oakleaf hydrangeas set bud on last years wood. So that means if you trim them in the spring you’ve trimmed off the buds and you will not be rewarded with big gorgeous football size blooms this year. Trim in the Fall! There are numerous cultivated varieties of this shrub from quite small to quite large. And they are NOT deer resistant. The damage usually happens in the winter, when the deer eat the soft tips off the ends of the stems. That’s it, damage done for that year….no blooms. As a matter of fact, it was this very shrub that convinced me to get a deer fence.
Hydrangea Paniculata "Limelight" and "Quick Fire". Both fantastic hydrangeas. Limelight blooms at the end of the summer when not much else is blooming. Quick Fire blooms in June and July. Just as Quick Fire is receding, Limelight is hitting her stride. That makes a very nice succession of bloom. The nice thing about this group is they bloom on this years new growth. So, even if the deer eat them in the winter, they still push out new growth, set bud and bloom. How does this work? Once the landscape leafs out the deer move on and usually this shrub does quite well. Trim in the Spring or Fall.
Hydrangea Arborescens has big puffy balls of whiteness blooming effusively in June and July. Easy care - the deer will browse on these but a deer spray like “Deer Stopper” used once a month will solve the problem. Please buy the container made to go directly into your hose and spray, I really mean douse your whole yard. The goal is for the deer to walk on by and over time that is exactly what they will do. Be persistent, consistent and diligent. I spray on the first of every warm month. Trim in the Fall or Spring to about 15”.
Hydrangea Petiolaris are climbing hydrangeas. These climbers have aerial roots that stick to a surface, like a tree trunk, a brick wall or a trellis with wide supports. In time, climbing hydrangeas develop lateral branches, where the buds form. One of my fav cultivated varieties is “Miranda”. This hydrangea petiolaris has lovely variegated leaves of creamy yellow and green. Miranda looks really great climbing on a shady red brick wall. Never underestimate the power of contrasting foliage with dark red brick to brighten up your landscape. Don’t trim the lateral branches, do trim to keep it off your roof or in your windows.
The Non-native Option:
Hydrangea Macrophylla - these are the pink and blue flowers that we all love. Trouble is this shrub hales from the southern region of our great nation and many cannot withstand the freeze thaw cycle of our zone 6 winters. And now I am going to throw a monkey wrench in the works, In the last decade or two a new group of hydrangea macrophylla’s have emerged that bloom on both this years and last years wood. This means even if the buds are zapped in the late winter the shrub will put out a crop of flowers later in the summer. trim out the dead canes anytime, trim for bloom if the fall
- Claire Schuchman
With over 15 years of experience, Claire's knowledge as a Master Gardener, brilliant execution of design, and dedication to the vision of her clients has been her passion. When she is not working in the field with her crew or meeting with clients, she strives to share her experience through teaching others.