If you’ve got a hydrangea, you probably have a question about it. And it’s no wonder why! Hydrangeas are natural garden centerpieces. Their big blooms play a huge role in the landscape so we want them to be as healthy as possible to keep the show going. As a result, we pay very close attention to them and any intrusive thought or sign of a problem makes us worry. So, we’re sharing answers to the five most commonly asked questions we get about hydrangeas in the summer to help you get back to just enjoying the view.
1. How do you know when to water a hydrangea? Is there a right way to water my hydrangea?
It depends mostly on how new the planting is and your weather. There isn’t a one size fits all formula to apply. Consider these factors:
- Newly planted hydrangeas need an attentive eye on soil moisture for the first year. They’re more often damaged by over watering than under watering, so only water when you feel that the soil is almost dry or dry. Then water deeply.
- Established hydrangeas planted in average, relatively moisture-retentive soil only need water during periods without precipitation.
- Potted hydrangeas will need frequent watering. Check at least every other day.
- One foolproof way to know what the soil moisture is in your garden is to use a moisture meter. Learn about them here.
Hydrangeas, as with most shrubs, prefer to be watered at ground level.
- It keeps their foliage free from excess moisture. Constant moisture just sitting on the foliage can encourage diseases like powdery mildew or black spot to move in.
- It keeps their flowers blemish-free for longer.
2. Why is my hydrangea flopping?
The key to sturdy stems for any hydrangea is proper pruning. Flopping is most commonly a problem with panicle or smooth hydrangeas, as you don’t prune mountain or bigleaf hydrangeas at all.
- Plan to prune your new wood blooming hydrangea in late winter or early spring. Only take off 1/3 of its height and width.
- Here’s a how-to video for pruning a smooth hydrangea.
- Here’s a how-to video for pruning a panicle hydrangea.
3. What sun exposure does a hydrangea really need? How do I know if mine is sited incorrectly?
It depends on the climate you garden in
- In cooler northern zones (3 to 7ish), most hydrangeas can withstand full sun (6 hours of direct exposure to sunlight)
- In hotter southern zones (7ish to 9), most hydrangeas will need shade in the afternoon when the sun exposure is the most intense to maintain a good appearance
and the hydrangea species itself.
- Panicle and smooth hydrangeas are quite sun tolerant, with panicles being the most tolerant
- Bigleaf and mountain hydrangeas generally enjoy getting afternoon shade
- Oakleaf hydrangeas are the most shade tolerant out of all the common non-vining hydrangeas, they produce the most blooms with the least sun exposure
- Sunburned leaves – a light brown cast over leaves
- Oakleaf hydrangeas are the most shade tolerant out of all the common non-vining hydrangeas, they produce the most blooms with the least sun exposure
4. How do you get the best, longest-lasting cut flower from a hydrangea?
- Gather when it’s cool outside – morning or night is best.
- Don’t gather blooms if they have water on them.
- Only select fully open flowers as budded blooms wilt quickly.
- Remove all lower leaves.
- Immediately put stems into water after cutting.
- Keep stems out of direct sunlight for at least 24 hours after gathering.
5. Why are my panicle hydrangea flowers turning brown?
There are three main reasons a panicle hydrangea would turn brown prematurely before giving its fall show of pink or red.
- Not enough water. If they dry out for a bit they will not be able to make the transition.
- Frequent water from above, often irrigation or just overhead watering. If water collects on the white blooms frequently, it will cause them to turn brown instead of aging to pink.
- Very high, sustained nighttime temperatures. If they are subjected to temperatures above 70 degrees for the entire day and night for an extended period of time they will not be able to make the transition.
If summer has you worrying about your hydrangea, but you didn’t see your question, please put it in the comments below. We can help!
7 Responses
I have 3 Bobo hydrangeas side by side, in Canada Zone 4. Normally they all have abundant blooms. Last year, one of them had almost no flowers. I thought maybe it was because of the prunus that was next to it, so I removed it. This year, that Bobo is full of blooms while the other two have none! They all get the same amount of sun and water and are in the same bed. Why am I getting inconsistent flowering?
What an interesting predicament. If you’re able to send me photos of your hydrangeas, we can go from there! – kristina@springmeadownursery.com
Thanks. I sent the pics by email.
This is the second year that my hydrangeas are not blooming. One is a shooting star and the other is a mop. The only things that they have in common is that they are in pots and have always bloomed on new stock. The foliage is beautiful, just no blooms.
There are a few possibilities! Feel free to send me an email with this info:
– What growing zone/area of the country are you in?
– How do you overwinter these pots?
How do I tell, if an unlabeled hydrangea (given as a gift), is a panicle or a smooth one?
Their leaves and overall habits will be slightly different. Feel free to email me a photo and I can help!