Here is professional guidance on how to put hydrangeas to bed for the winter season from guest bloggers Megan Nichols and Jessie Jacobson of Tonkadale Greenhouse in Minnetonka, Minnesota. (They may have more hydrangea trees and shrubs in their zip code than almost anywhere else in the United States, so they are aware!)
The temperature has dropped, and autumnal symbols can be seen everywhere. The garden needs to be put to bed soon. Hydrangeas reward us with large, stunning, and prodigious blooms all season long. You may say that they are givers. It’s time to return the favor now. It’s time to tuck the hydrangeas in with kisses and wishes for sweaty dreams.
Here in Minnesota, our moods can fluctuate as drastically as the unpredictably harsh winter weather extremes, snowfall, and freeze/thaw cycles. Despite the fact that many hydrangeas are regarded as hardy, all of this can confuse them. To survive the winter and come back bigger and better the next year, they require some care. Although hydrangeas cultivated in warmer areas don’t need as much post-season primping as those grown in our zone, there isn’t a single thing that wouldn’t appreciate a little tender loving care right now.
Utilize these suggestions to get the most out of your hydrangeas so that you can be the one to present at this time next season!
(Is pruning in order? No and yes. Here is our recommendation for which hydrangeas should be pruned right away and which should wait until spring.)
Don’t Stop Watering
Make a commitment! I shall water my hydrangeas till the earth freezes solid, you declare while raising your right hand. really good Hydrangeas are thirsty plants by nature, so it’s essential to give them regular, deep watering. We don’t need to get all linguistically nerdy right now, but their name literally means “hydration.” Winter’s cool, dry winds completely drain the moisture from the vegetation, and hydrangeas don’t use lip balm. It need not be heated in order to be dry!
If a freeze is not a concern where you live, water deeply but sparingly during the winter depending on how much rain you get.
This is how: Making a small hole in the side of a 5-gallon bucket, filling it with water, and placing it at the base of the plant while it slowly drips out of the bucket is one method. Another option is to lay your hose at the base of the plant for about an hour with the water turned on to a gentle drip.
Give Them One Last Hearty Meal
Composting your hydrangea beds in the fall will give them a boost for the upcoming growing season. Everyone feels better after a full night’s sleep and a filling breakfast. This also applies to hydrangeas. After a lengthy winter’s hibernation, they will be ravenous for some nice compost. Compost can decompose during the winter if it is used now, making nutrients easily accessible in spring. A few inches of compost is advisable even in regions without a deep cold. Only compost is being discussed here! Don’t give your hydrangeas fertilizers that are high in nitrogen because this can encourage them to produce new foliage growth.
This is how: Before laying down mulch in colder climates, top dress the area with compost, well-aged manure, or other organic material after the ground has frozen. This organic fertilizer, which is rich in nutrients, will decompose over the winter, making nutrients available to the plant in the spring. Apply compost in the late fall or early winter in zones that are warmer.
Mulch Matters
Mulching helps keep moisture in and weeds out in warmer climates while shielding the crown and roots of your hydrangeas from harsh winter temperatures in colder climates. Snow serves as a natural insulator if everything goes as it should. Plants suffer during strange winters with little snowfall and extreme temperature changes. Apply a thick layer of mulch around the plant’s base to offer hydrangeas the best chance of flourishing. While decorative mulch is useful, straw, marsh hay, or dead leaves are suggested instead.
This is how: Apply a 6–8 layer of mulch once the ground has frozen (or late fall or early winter in zones with milder winters). This shields plants from the heave-ho of springtime freeze/thaw cycles, which can yank them out of the ground. Inviting mice to make this their snug winter home, causing rotting and illness, or tricking the plant into believing it’s time to bud, are all consequences of mulching too early. Be patient; you don’t have to do things early simply because your neighbors are.
Keep Them Cozy
The amount of winter cold determines whether or not hydrangeas require protection. Winter protection is not required in zone 7 if the air temperature stays above zero degrees. Wrap or totally cover barely hardy hydrangeas in chilly areas. This is crucial for plants that bloom on old wood, such hydrangeas with mop heads and large leaves (Hydrangea macrophylla). The most recent types of mop head/big leaf hydrangeas, however, bloom on both fresh and old wood, so it’s important to keep that in mind. In their favor and ours! Hardier hydrangea varieties like the paniculata and arborescens don’t often require additional winter care, although really low temperatures might cause its limbs to die back. Consider covering if a colder than usual winter is forecast.
This is how: Wrap plants loosely in a few layers of burlap, making sure to tie it off with strong twine. Making a mulch mountain and covering the majority of the plant is an additional choice. Smaller, newly planted specimens respond well to this technique.
There’s Still Time To Plant!
The first three varieties of hydrangeas can be grown here in Zone 4; oak leaf hydrangeas can also be grown in warmer climates (zones 5 to 9). The optimal time to plant shrubs is in the fall. Just make sure to do all of the aforementioned things, including watering and mulching.
Here are some of our favorites that you can plant now for stunning blooms the following spring.
Panicle Hydrangeas
These late blooming hydrangeas, also known as PeeGee hydrangeas (summer into early fall). They are covered in elongated, conical flower heads that emerge white or green and blush into pinks and peaches as the season goes on.
How should winter hydrangeas be protected?
Since I’ve been doing a radio show on Pittsburgh’s KDKA Radio for ten years, the most frequent query my co-host and I get is “Why doesn’t my hydrangea bloom?
Upon further enquiry, we invariably discover the caller is looking for information on Hydrangea macrophylla, a big-leaf hydrangea. These traditional hydrangeas produce lovely balls of pink or blue flowers, but in the northern United States, they are infamous for their unpredictability. They can blossom wonderfully one year and not have a single bud the following. Here are some suggestions you can implement right away to improve the blooms on your hydrangea if you’re a gardener in USDA zones 5 or 6 and have had similar experiences.
1. With very few exceptions, Hydrangea macrophylla cultivars like the double-flowered variety “Paraplu” develop their flower buds on ancient wood. This implies that the buds inside those seemingly dead twigs are actually the blossoms for the following year. Future blossoms are taken off if any branches are pruned now or in the spring. The optimum pruning method for big-leaf hydrangeas, according to my radio co-host and I, is to do none at all.
2. Cold temperatures and drying winds can harm the dormant flower buds trapped inside those brown sticks. The sporadic late-spring freezes are particularly harmful. Put a layer of protection around the plant to safeguard the dormant buds on your hydrangea. Each plant should have four 1×1 hardwood stakes hammered into the ground. Burlap or black landscape fabric should then be stapled to the posts surrounding each plant. Make sure the fence is as least as high as the plant. Avoid covering the top; the weight of any accumulated snow could cause the entire structure to topple over onto your plant. Till the hydrangea’s buds begin to swell in late spring, keep this protective castle in place.
3.Big-leaf hydrangeas typically perform better if placed in a more protected area. If at all feasible, move any non-blooming specimens to a corner that is shielded from strong winds and close to a road or wall that absorbs heat. The optimum times to transfer hydrangeas are in the early spring, before the leaf appears, or in the fall, just before the ground freezes.
4.You might want to think about including a couple different species of hydrangeas in your landscaping for more dependable bloom production. A slightly hardier form known as hydrangea arborescent develops enormous white flower clusters that resemble snowballs. My favorite cultivar is “Annabelle.” The oak-leaf hydrangea, H. quercifolia, is another extremely dependable bloomer with magnificent fall color and white conical blooms. However, there are a few cultivars of H. macrophylla that are currently available that have been chosen for their ability to bloom on both old and new wood. With a more recent introduction dubbed “BloomStruck,” I’ve had the most success.
What is your favorite hydrangea, and how do you keep it safe during the winter?
Do hydrangeas require protection throughout the winter?
The majority of defense strategies begin with a frame around the flower. This can take the form of strong stakes encircled by burlap, chicken wire, or any material that allows air to flow (Plastic is not recommended although some find it useful).
The sketch to the right depicts a dormant hydrangea enclosed in a wire cage, and you will certainly want to acquire a copy for your art collection. (One reader suggested using cardboard to line the interior of this cage.)
The box is then filled with an insulating material, such as pine straw, oak leaves, or something similar. Avoid breaking any of the branch tips, as this are where the flower buds have already developed. (One reader advised wrapping insulating material across the entire cage at this point.) Until the last possible frost has passed, this needs to be left on the hydrangea throughout the winter and into the spring. The hydrangea will already be leafing out when it is exposed.
It’s crucial to cover the extremities of the branches throughout the winter because hydrangeas frequently place their blossoms there. The majority of insulating materials need to be replaced or fastened in place because they tend to pack down a little throughout the winter and expose the branch tips.
Belgian hydrangea specialist Luc Balemans issues a warning that certain winter covers (like the one on the left) may scrape the ends of the branches off under windy conditions, which will then rub off the bloom buds. Before covering, a layer of leaves or other material should be used to preserve these crucial bloom buds at the extremities of the branches.
As was already indicated, leaves frequently settle throughout the winter, exposing tender buds. One gardener claims that because oak leaves don’t compact like other materials, they provide for exceptionally good insulation. An additional gardener advised storing extra bags of leaves in a location where they won’t freeze. The leaf insulation can then be refreshed with these when the winter settles in. We were able to uncover some decent selections online for individuals who don’t have time to visit their neighborhood garden center or are searching for something a little less expensive.
Do I need to take any extra steps to protect a hydrangea if I’m growing it outside of its proper growing zone? Should I cover them in burlap or another kind of covering like I might with other shrubs?
Giving it an additional blanket for the winter is a good idea if you’re trying to grow something in a somewhat hardy environment. You’ll likely need one or two more layers than someone who usually experiences the cold when you get off the plane from Hawaii to Minnesota in January. Burlap does offer some nice protection for the shrub, but you might also want to consider enclosing the shrub in a metal cage and stuffing the cage with pine straw or leaves before wrapping it in burlap.
How often should hydrangeas be watered over winter?
You shouldn’t have to water plants all winter long if you live somewhere that gets snow. You might need to apply once per month or so if you live in a warmer area without snow and little winter rain. You can leave it unless it’s completely dry because the plants’ water requirements are small because they aren’t growing and have no leaves. The same is true of container-grown hydrangeas. Easy as pie.
First Editions ‘Vanilla Strawberry’ Hydrangea
A panicle hydrangea called “Vanilla Strawberry” blooms from midsummer until the end of the season with sweet-colored blossoms. Cut down or shape plants in the late winter or early spring before blooms appear. Vanilla Strawberry is a standard that can grow to a height of 6 feet.
Don’t give up on it in the winter and fall. This time of year, they are intended to shed their leaves. If there isn’t snow cover, make sure it keeps hydrated all winter. The plants still need some hydration at their roots even though they are dormant. Snow cover serves as a water source as well as insulation. Make sure you have enough rain or water to get them through if you live somewhere where it doesn’t snow or doesn’t receive snow. Additionally, make sure mulch, such as wood chips, oak leaves, pine straw, or another type, is placed over the hydrangea’s base. Snow or no snow, it provides the necessary insulation as well as some extra defense against hungry rats and rabbits in the winter.
When trimming other plants in the late winter, you might be tempted to prune hydrangeas as well, but McEnaney advises that you should first identify the type of hydrangea you have before using pruning shears.
Remember, he says, to offer a minor clip in the spring if you have a reblooming or mophead hydrangea.
Late winter is the time to prune down cone-shaped hydrangeas by a third to a half. Prune a cylindrical oakleaf variety after midsummer flowering if you have one.
When in doubt, McEnaney advises against pruning in the fall.
You run the risk of jeopardizing your flowers for the following year by cutting off blooms that grow in the fall. Simply be patient and wait until spring to prune after this season’s blooms have provided you with some winter appeal.
Ask for assistance from a nearby nursery, garden center, county extension office, or even another gardener to identify it if you are unsure of the variety.
According to him, too much fertilizer can be detrimental.
The element that promotes bloom production and gives you the most value for your money is phosphorus, so seek for a fertilizer with a high concentration of it when you’re at your neighborhood garden center. Follow the instructions on the fertilizer package and avoid overfertilizing to avoid burning the root system and preventing the development of flowers. If anything, one more application of fertilizer in the middle of the summer is beneficial, but make sure to cease fertilizing by early fall.