When to winterize

7 years ago

last modified: 7 years ago

When do you know it's time to winterize your hydrangeas? I read that winterizing too early is not good so I've been holding off as long as possible. It's supposed to go down to a degree or two below freezing at night coming up later this week, so hopefully I didn't wait too long.

Featured Answer

luis_pr

7 years ago

last modified: 7 years ago

Generally speaking, such a small drop below freezing m-a-y be ok and you could wait until it goes dormant ( leaves and blooms both brown out). For example, last week we went down to 30 and then down to 32 but the leaves were not affected. Sometimes the shrubs are zapped and the leaves look puny, blackish and then I winterize after that. But down were I live in Z7b/8a, that usually happens in late Nov or early December. So I wait until the plant goes dormant.

In cooler climates though, you may have an early dip where temps suddenly go way much lower (think 20F or so) and theeeen it may be better not to wait to winterize. If winter were to arrive with such a very low temp (or less) and the plant is green & in "grow" mode then water deeply and winterize early.

PS - Make sure that the soil is deeply watered before it goes below freezing. I have had other years where temps went down to 32 also and the leaves got zapped so... providing some water helps. This year, I did not water because Mother Nature rained on them for three full days before we dropped to 30 and 32F.

Arborescens (Annabelle-like hydrangeas) and Paniculatas (Pee Gee-like hydrangeas) do not need to be "winterized". ;0)

Sort by:Oldest

Comments (10)

hyed
7 years ago
Patti, where are u located what Zone
Patti JS zone 6 ON thanked hyed
Related Professionals
Muskogee Landscape Architects & Landscape Designers · Barnstable Landscape Architects & Landscape Designers · Sacramento Landscape Architects & Landscape Designers · Frederick Landscape Contractors · Pocatello Landscape Contractors · Dalton Design-Build Firms · Rome Design-Build Firms · Chattanooga Design-Build Firms · Winona Design-Build Firms · Portsmouth Design-Build Firms · Akron Design-Build Firms · Toledo Design-Build Firms · Youngstown Design-Build Firms · Montrose Design-Build Firms · Lubbock Design-Build Firms
Patti JS zone 6 ON
Original Author
7 years ago
Oh sorry, I did add it to my profile name, not sure what happened to it. I'm in the Toronto Ontario Canada area - zone 6a.
Billy (Zone6 Mass)
6 years ago
We've had a couple nights where the temps went below freezing. Lowest so far was high 20s low 30s. I just put the stakes around the shrub but haven't fully winterized yet since there's still leaves on the shrubs (barely). I think i'm going to give them the rest of this upcoming week to go fully dormant and i'll plan on fully winterizing this upcoming weekend. I'm in zone 6 in Mass. Last year I winterized around this exact same time.
Patti (z6a ON Canada)
6 years ago
We just got a huge dumping of snow here and I wasn't prepared - about 6-7". I did manage to put a few inches of mulch at the base of each one before the snow started coming down really heavy, and quickly wrapped a couple in burlap. I didn't even have time to try the cardboard flattening method. The little ones are covered in snow now with no coverings. Two bloom on old and new wood. I hope they are ok. We usually don't get snow here until the middle of Dec.!! Not a happy camper/gardener.
luis_pr
6 years ago
We got down to 24F this morning. No snow but a little precip during the day when it was still in the 50s. Incredibly windy; about 20-25mph and higher gusts. One smoke bush lost a branch. Many yellow leafed trees have few leaves now. I have not looked at the hydrangea leaves to see if they turned dark green or blackish. The oakleaf leaves are turning red, brown.
kitasei
6 years ago
I wrapped my macrophyllas with leaves that were still wet. The hydrangeas themselves hadn’t lost their leaves. They hadn’t even turned brown or crispy. And I didn’t cover the tops where the all critical buds are yet. Despite all this I believe the real danger doesn’t come til spring with early thaw late frost. My plan is to throw something on the tops in that case. Really have to wonder why I have persevered for six years with these plants. Unattractive in winter, bare sticks in spring great blobs of green with a smattering of blue balls hidden deep in the foliage in summer, limp blackened leaves in the fall.. why why why do I persist? Becsuse I remember my mother’s glorious hedge every summer in coastal Rhode Island?
Billy (Zone6 Mass)
6 years ago
last modified: 6 years ago
I'm going to have a couple nights this week in the high teens low 20s. Didn't get around to winter protecting them since I was planning on doing it this weekend. If they are damaged.... I'll have some nice foliage plants next year =(. We don't normally get temps that cold in early to mid Nov....
gardengal48 (PNW Z8/9)
6 years ago
I never protect mine......not really any need to here. But I do need to report that a few years ago we had an unusual weather event in November. Went from a record high (74F) to a record low (19F) in less than 24 hours!! And with about 18" of wet snow as well. Lasted for 3-4 days before evening out to more normal weather but not a sign of any distress with the hydrangea flowers. Bloomed just as heavily as they always do.

Although you cannot prove it by me but I do believe the fluctuations in late season temperatures causes the greatest distress and risk to the nascent flower buds. Starts warming up, plants start to leave dormancy, buds begin to swell and then an overnight cold snap wipes it all out.
Billy (Zone6 Mass)
6 years ago
last modified: 6 years ago
I agree with you GardenGal. I think the damage you really want to protect against is late winter/early spring temp swings. Like you said, you get a warm spell in March, shrub thinks it's time to come out of dormancy and shoots out new growth. A cold front comes through and damages new growth and you are left with a foliage plant for the season.

Right now the shrub is going dormant and the green canes are hardening into brown woody canes. It's not shooting out any new growth at this point so a couple cold night in November shouldn't damage anything. That's my current understanding.

I will say this past growing season, tons of Macro's in my area bloomed really well and no one winterized them. We actually had a very mild late winter with no damaging frosts. I'm convinced this is the reason why we had such a good blooming season this year. The 2017 growing season, not a single one in my area bloomed...