PETITTI | How to Protect Bigleaf Mophead Hydrangeas for Winter 

Happy holidays!

Happy Gardening!

I was thinking the same thing. You'd have to like take a mini table or something to account for the weight of a large snow fall that would crush the bag.

put a laundry basket over it all to account for that heavy snow... try and stake the basket to the ground so the wind won't take it.... problem solved.

Because the soil temperature is still warm, the first few fall frost events rarely affect the hydrangea stems and immature buds on them. Fall frosts will trigger the leaves to turn and fall which you want to come off and rake up before wrapping the plant and/or spraying the stems with Wilt-Stop.

If you have had 2 or more killing frosts (below 32 degrees F) and your leaves are looking dead but still hanging on, you can strip them off by hand. If the plant has not experienced enough cold to be fully dormant, I suggest waiting until you get colder temperatures in your area before applying protective materials.

@@PetittiGardenCenters Thank you! We have had several nights that cold, but the majority of leaves are still green and hanging on. I’m wondering if it’s because they are against the house and somewhat sheltered. I’ll wait til the next frost and strip leaves after that. Thanks for the expert help!

You want your hydrangea to experience a couple hard frosts before covering for the winter! You also want to make sure to remove all of the leaves that are left on the plant and around the plant.

@@PetittiGardenCenters, doesn’t these first few hard freezes or frost kill off next years blooms?

This variety of macrophylla hydrangea should have no major issues wintering over in Zone 7. It's rated for Zones 4-9 & 5-9, so you are located right in the middle of the temperature range, which is a good place to be as far as root cold hardiness is concerned. However, the above ground branches & buds can become damaged as temps drop, de-harden & reharden as winter temps fluctuate. Macrophylla Hydrangea stems may be hardy to 0F, but buds tend to get damaged around 10-15F. It is beneficial to mulch Macrophylla Hydrangea 2-6" for the winter after their leaves fall off to keep the soil moist and moderate soil temps. For added piece of mind you can also try spraying their stems/buds with anti-desiccant like Wilt-Stop to seal in moisture. It can't hurt to wrap them with burlap as well if that is your preferred winter protection. Just know that this variety is repeat blooming, producing buds on old and new wood, so if the older stems & buds get damaged, the newer will grow and develop flowers regardless.

Bobos are Panicle Hydrangeas, which are much hardier than Macrophyllas. They don't require the same winter protection shown here. We recommend waiting to do hard pruning until the spring and protecting the base of your Bobo with a thick layer of mulch.

Yes, you can keep them in the garage for winter, but I suggest letting them go fully dormant outdoors to the point that they have lost most of their leaves before placing them in the garage for the winter. Water them lightly 1x per month and slowly acclimate them to the outdoors when new growth begins in spring. Another option is digging the holes where you plan to plant them now, sink the potted hydrangea in the hole, backfill around the pot and mulch 4-6" around the plant. We always recommend wrapping H. macrophylla in burlap for winter to protect buds already formed on their stems too.

@@PetittiGardenCenters thank you so much ! I brought them in while we had a cold snap and snow but put them out again for the sun we will get . I haven’t decided where to put them as my house faces east and my beds are pretty full .. I was thinking of placing them along the south garage wall that has a large Japanese Maple in front .. It’s almost a protected alcove since it is front of the library window ..

@@PetittiGardenCenters thank you ! I put them back out for some sun as the weather cleared up . Have no spot yet to plant them in as my beds are pretty full. I am thinking of planting on the south side of my garage wall which is like an alcove with the east facing library wall and a large japanese maple in front .