Winter-proof your hydrangeas with these tips.
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Hydrangeas are brimming with nostalgia, stirring memories of endless Southern summers.
When winter arrives, these charming plants need a little TLC to ensure summer blooms return the following season.
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Hydrangea plants also benefit from protection against fluctuating winter temperatures, which can disturb the roots and crown.
Four different types ofhydrangeasare commonly grown in American gardens.
Bigleaf and oakleaf hydrangeas are more sensitive to flower damage during the winter months and often require additional protection.
All four species benefit from the right winter care to keep plants healthy and thriving through the toughest winters.
Hydrangea species vary in their winter hardiness as well as pruning needs.
One of the biggest differences between hydrangea species is when they set flower buds.
If you are unsure which jot down of hydrangea you have, start by looking at the foliage.
Hydrangea blooms are your next clue to identifying plants.
Bloom time is your final clue.
Panicle and smooth hydrangeas flower later in the season, typically from June to September.
Proper irrigation is critical, even when leaves have fallen from plants.
Continue to keep plants watered until the ground freezes or snow falls.
Adjust irrigation to account for rainfall and do not water over the top of snow.
Apply a thin layer of compost in late fall or early winter.
Mulch also helps retain soil moisture and manage winter weeds.
These buds are exposed to winter winds and freezing temperatures throughout the winter.
Extremely cold weather or late spring freezes can damage these flower buds.
The leaves provide insulation.
Next, wrap the plant with a couple layers of burlap, securing it with twine.
Panicle and smooth hydrangeas produce flower buds on the young growth that emerges in spring, called new wood.
Likewise, when extreme weather occurs, all hydrangeas will require extra attention.
Pay attention to temperature extremes during the winter.
As such, the winter hardiness zones are not accurate for potted plants.
Container plants will need additional protection, especially in the colder range of these zones.
Mulch the soil and keep plants watered throughout winter.
Containers dry faster than ground soil, so be sure to check them more regularly.
Another option is to dig a hole and bury the plant, container and all, for the winter.
This helps moderate soil temperatures.
Also use this method to insulate container plants overwintered outdoors in the cold end of its winter hardiness range.
Keep the roots moist but not wet, watering containers once per month with about one cup of water.
Water plants well and fertilize about every two weeks.
Plants can be brought back outdoors after the threat of frost has passed.
Knowing when the flower buds develop helps you determine the proper time to prune your hydrangeas.
Pruning these plants during the winter would remove the flower buds, leaving us with a bloomless plant.
Timing is not the only consideration when it comes to pruning.
Plant habit and desired size also direct how the different types of hydrangea plants are pruned.
These scaffold branches help support new growth and keep those large, heavy blooms upright.
Panicle Hydrangea
Prune panicle hydrangeas in late winter or early spring before new growth emerges.
Pruning is not necessary but can be used to increase blooms, shape plants, or control plant size.
Another option is to prune your hydrangea into a tree with a single or multi-stemmed trunk.
Panicle hydrangeas are the only species that can be pruned into a tree form.
At this time, strong new shoots will be developing from the crown of the plant.
Oakleaf Hydrangea
Oakleaf hydrangeas require very little pruning.
Dead or damaged branches can be removed any time.
Your best bet is to rely on plant hardiness and winter temperatures as your guide.
Protect bigleaf and oakleaf hydrangeas when airtemperatures are expected to fall below 15F.
For panicle and smooth hydrangeas, provide protection when temperatures are predicted to dip below 0F.
Even though hydrangeas are dormant during the winter months, their roots still require moisture.
Water plants once per month throughout winter or until the ground freezes or snow falls.
Leaf shape, flower habit, and bloom time all provide clues to identifying your plants.
In mild winter climates, potted hydrangea plants can outdoors with little protection.
Potted plants can also be buried in the soil, container and all, to provide winter insulation.
