oakleaf hydrangea- what variety is the hardiest?

5 years ago

Any opinions as to whether there's a variety of oakleaf hydrangea that's most likely to survive and thrive in zone 4.

I planted a ruby slippers plant last fall- I did put some old vegetation over it to mulch it some- it's survived and is blooming beautifully now.

I'd like to put some more in a separate location. Any opinions as to which cultivar (or the native form available from fedco) is most likely to survive my zone 4 winters?

Thanks

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Comments (4)

gardengal48 (PNW Z8/9)
5 years ago
I am not aware of any variety or cultivar of Hydrangea quercifolia considered to be any more winter hardy than another. Virtually every source you will find, including Dirr, lists them as a zone 5 plant regardless of selection, but not lower.

That is not to say that the siting of your Ruby Slippers isn't being influenced by whatever microclimate may be available in that location that is allowing it to survive. But I couldn't speak to the same degree of success with any other placements nor if your current Ruby Slippers will continue to survive your winters and thrive. Maybe.......maybe not :-)

And maybe your zone is not as severe as you think or is undergoing some modification that is making winters less harsh. But at best I would consider it to a be a marginal plant for your area.

The best thing about oakleafs growing in colder climates is that they will almost always flower. Even though flowers are produced on old wood, winter cold does not appear to have the same damaging effect on latent flower buds as it does with macs. Stem dieback from cold is a different matter - that can and does happen in colder locations - but if the stems survive the winter (no dieback), chances are very good that they will produce flowers.
Nobasil (z4 New England)
Original Author
5 years ago
Thanks that's helpful.

I think the zone is still zone 4, but it may be that our microclimate is more tolerant. We're basically on the side of a gentle 1-2 mile slope, so we don't get mountaintop or hollow conditions.

I was hopeful that the ruby slippers survived this past winter. I did mulch it well. However we had a terrible cold snap in January (worse than average)- it was below 0 for days and easily got below -20 several times. The plant had only been in the ground since the fall. I really like the plant, and figured that if it could survive those conditions it may be that I can plant more.
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Nobasil (z4 New England)
Original Author
5 years ago
This is the ruby slippers I put in last fall that has less than a year in the ground. The comments here and on the post I started about a new shrub border are making me think either I got lucky and found a sheltered spot- or maybe ruby slippers is the answer to my original question.

oakleaf hydrangea- what variety is the hardiest?

Comments (4)

gardengal48 (PNW Z8/9)

Nobasil (z4 New England)
Original Author

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oakleaf hydrangea- what variety is the hardiest?

Comments (4)

gardengal48 (PNW Z8/9)

Nobasil (z4 New England)Original Author

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stir_fryi SE Mich

Nobasil (z4 New England)Original Author

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GET HELP

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Nobasil (z4 New England)
Original Author

Nobasil (z4 New England)
Original Author