dcamp1017
Full Member
Posts: 10
Joined: Wed Jun 16, 2010 11:02 pm
Location: Ohio

Hydrangeas hit by freeze

Hello,

I live in Northeast Ohio. We had an unseasonably warm March and my hydrangeas got leaves and buds very early. Then in April we had cold weather and a couple of overnight frosts. All of the leaves on my hydrangeas turned black and are falling off. Do I cut back the wood (which still have some unopened buds)? Are the bushes lost for this summer? Please advise. I have never had this happen before.

Thank you,
Donna
I love summer!

luis_pr
Greener Thumb
Posts: 815
Joined: Sun Jul 05, 2009 12:31 pm
Location: Hurst, TX USA Zone 7b/8a

Hello, Donna. The shrub per se is most likely fine since the roots should not have been affected by the freeze; it just looks ugly, pitiful or both. Let it put out new growth as soon as it can and then evaluate what to prune and how. Normally, it is hard to reliably determine which leaves, which flower buds and which stems will make it and which will not. It is best to wait a month and then evaluate how these parts are doing then.

With stems, sometimes parts are affected but other times the whole stem can dry out. Luckily, these are woodsy plants so the stems tend to be quite tough. So, it is best to do no stem pruning for a while. And observe if all parts, some parts or no parts leaf out. Usually, that alone will tell you how you will need to prune. Personally, I wait a year to prune stems.

When this problem happened to me, I waited about a month + or - before seeing new growth. By then, the leaves that did not make it turned brown; I then crushed them with my hand and left the stem as is. If you "have to have to" cut and cannot wait to remove the affected leaves, try cutting the petiole. That is the little "stem" that connects the leaf to the stem. The leaves looking blackish tend to be the ones that will not make it.

After waiting at least a month for my hydrangeas to recover, I noticed the injuries were small and new growth was coming out. Well, I left all of my affected leaves and stems "as is" because the new foliage covered most of damage and because I can be lazy. Then surprise! Some of the affected stems actually leafed out the next Spring. I had painted some marks to help me identify where to prune and I was seeing growth above those pruning marks. If you cannot stand the look of dried out stems, try this: prune in 1" increments from the top to the bottom; and stop when to get to green or when you hit the bottom.

In the meantime, maintain the shrub well mulched (3-4" of mulch) at all times. Maintain the soil evenly watered as well. The soil should not be wet; and it should not suffer from periods of extreme dryness followed by periods of wetness. Because the shrub is stressed, do not fertilize it now.

Since you are in the northern half of the country, you can simply feed them once, in June (assuming it has recovered by then). That should do it for the whole year.

For a newly planted hydrangea, you can use 1/2 to 1 cup of compost, composted manure, cottonseed meal or you can use a general-purpose slow-acting chemical fertilizer. Or if your soil has no mineral deficiences, you can skip feeding it all this year. Hydrangeas are not heavy feeders like most roses are and, nothing will happen if you just forget to fertilize on some years. I have had some shrubs that have gone w/out fertilizers for a year and it has not impacted flower production.

Once the plant has recovered, you can also add "weak" fertilizers like liquid seaweed, liquid fish or coffee grounds. But stop applying all fertilizers by the end of June so all that nitrogen will not keep the plant awake.

Flower buds are located near the end of the stems for many hydrangeas and they are not visible so it is hard to tell if the cold damaged them. My shrubs are starting the broccoli stage now. Yours should start that in May. If you get no broccoli stage by the end of May then the freeze damaged them as well. However, if this happens to be a rebloomer hydrangea, you will still get another shot at flowers, just later on in the year... say June-ish or July?

Keep your hopes up. When my hydrangeas were kept awake by a warm Fall and early Winter, the flower buds got zapped when we got hit by 5-6 days of sub-freezing temperatures. :shock: In April, it was bad. But at least I got two blooms by two mopheads. At least I got something! :wink:

Luis

tay666
Full Member
Posts: 26
Joined: Fri Jun 10, 2011 12:49 am
Location: North East Ohio

I am in the same boat.
Also in North East Ohio.
I have a well established Nikko Blue that is about 6 feet tall.
I'm not worried about permanent damage, as I don't think anything will kill this bush it's been through just about everything mother nature can throw at it.

Mine also leafed out early thank to the weeks of 60-80 F weather we had in March. But the frosts and the cold weather of April have taken a toll.
The buds turned black and fell off.
But what I am curious about are the leaves. Most of the leaves on the bush are now deformed. They look wilted and sickly as well as misshapen.
They have been like this since the cold weather last month.
I know they aren't going to fix themselves. And they show no signs of falling off either.
Some new growth at the bottom of the plant looks good. But it is on long thin shoots that have a ways to go to get out from under the rest of the bush to get light.
Should I just leave the bad leaves? Will they still be able to support the plant?
Or should I prune the bush back, so the new growth can better get light?

luis_pr
Greener Thumb
Posts: 815
Joined: Sun Jul 05, 2009 12:31 pm
Location: Hurst, TX USA Zone 7b/8a

Sorry to hear that, tay666. One of these days, someone will develop an instrument that will generate an email when we need to hurry and tale proactive steps due to incoming frosts. Actually, would it not be grand if someone actually made a little robot that would also take care of putting protection on the shrubs too. What's that you say? Not a chance? Hee hee hee! Oh well. :D

Sometimes the leaves brown out when they cannot recover from the frosts. Other times they appear "normal" but much smaller than they normally do. Other times the leaves stay small, shriveled as you describe.

At this point, you need to decide what to do going forward. Many people will decide to prune for aesthethic reasons. From your comments, it sounds like that is the way to go.

The existing leaves may not support the plant as well as normal leaves do but being a well established shrub, it probably would survive if left alone and monitored. But the shrub would probably look strange.... many of the long stems would end up with bare long spaces and with small or shriveled leaves spread only here or there. Odd looking, not quite pretty as before.

That is why many people opt to prune the stems down, all to the same height.

tay666
Full Member
Posts: 26
Joined: Fri Jun 10, 2011 12:49 am
Location: North East Ohio

I figured there would be trouble when we were hitting 80F in March.
The biggest problem was for how long we had the warm weather. A week or 2 wouldn't have been a problem. But we had almost a month of unseasonably warm weather, that kick started everything.
Then things went back to 'normal' in April. Wasn't just one or 2 freezes, but extended periods of cold. With a few freezes thrown in for good measure.
My daffodils and rhododendron managed to bloom before the cold weather came back. So, I at least got to enjoy those blooms. Even though it was only for about a week until they got zapped. My tulips sent their leaves up, but then the cold hit and and the leaves went limp and never recovered, and never got one flower stem from any of them.
Once I saw leaves on the hydrangea, then the cold hit, I figured it would be a bad year for it. Was surprised that I didn't loose the leaves completely. Just lost the buds.
Now I see some signs of flowers on the new growth. But I don't know.
the stems they are on are like 3-4 feet long. With a good 2 feet under the bush with nothing on them. As the new leaves get bigger, the stems are starting to droop down onto the ground. Which makes me worry about possibly picking up some kind of disease. Can't be good for leaves and stems to be laying on the ground where they can't get any kind of air circulation.

I think I might just cut the whole thing back to about 2' tall.
I've been thinking that I should move the plant anyway, as it is out of space where it is now. Rubbing against the house and hanging out over the driveway.
Put it out in the yard where it can spread and have more space.
Only thing is, though. The best place I have will have opposite sunlight cycles.
Where it is now, it only gets late afternoon sun (west side of the house).
The new spot would have morning sun, and shade the rest of the day.
I know this is actually what is considered optimal for a hydrangea, but this one has been thriving where it is.

I need to make up my mind soon though.
Because if I do cut it back and transplant it, I want it to have time to get established before we get into the heat of July and August.

luis_pr
Greener Thumb
Posts: 815
Joined: Sun Jul 05, 2009 12:31 pm
Location: Hurst, TX USA Zone 7b/8a

In the northern half of the country, hydrangeas can get more sun than they do down here. So switching the shrub to the other site will not cause harm but it may reduce the amount of bloomage some if it gets less sun. But the resuction may not be a noticeable amount. Because of all the trauma this year, I would expect less bloomage in Spring 2013 and normal amounts by Spring 2014. The only thing to keep in mind is that we are approaching summer, a bad time to be transplanting shrubbery like hydrangeas

Perennialnorthernmichigan
Full Member
Posts: 13
Joined: Mon May 14, 2012 1:28 pm
Location: Michigan

All my friends and I have the same problem. It's funny because I have heard that question so many times in the last month. I even questioned whether I should cut my stalks because they are an eye-sore in my garden, but they are starting to get green foliage again, slowly but surely. I just picked the brown-dead foliage away to encourage new growth.

tay666
Full Member
Posts: 26
Joined: Fri Jun 10, 2011 12:49 am
Location: North East Ohio

Yeah. I decided against the transplanting for now.
We got a couple days of rain, and the plant just exploded. More leaves, and I have lots of blooms starting to form now as well.

This is good. Gives me more time to plan out the move. Because it does need relocated. Right now, it is 6' tall, over 8' across, but it is squished to about 5' deep because of being between the house and the driveway.

Return to “Hydrangea Forum”