Can You Grow Hydrangeas in Hardiness Zone 3? (2024)

Hydrangeas are a popular shrub all over the world, especially in the United States. Their large colorful flowers make it easy to see why we love them so much. But do they grow in colder climates like USDA Hardiness Zone 3?

There is a hydrangea for almost every gardening situation. From container gardens, to climbing vines, or full sun there is an option for you. And yes, there are some varieties that are even fairly well suited for colder climates.

So, if you live in hardiness zone 3 but aren’t sure if you can grow hydrangeas this season, you’ve come to the right place. Let’s learn a little bit more about this popular shrub and how you can make them work for your cool climate garden!

The Long Answer

Now that you know that some types of hydrangeas are able to be grown in this hardiness zone, let’s take a look at some more important details. It’s important to understand the climate of hardiness zone 3, as well as what varieties will give you the best shot at survival.

Let’s dig a little deeper into what you can expect, and how you need to plan for colder weather when it comes to both care and maintenance.

USDA Hardiness Zone 3

Zone three is a chilly portion of the United States on the most northern border, including portions of Montana, North Dakota, and Minnesota. There are spots dappled throughout the following states as well: Alaska, Colorado, Idaho, Maine, New Hampshire, New York, South Dakota, Vermont, Wisconsin and Wyoming.

These areas have a minimum average temperature ranging between -30 and -40 degrees Fahrenheit. It is important not only to keep your temperatures in mind, but the climate as well.

Best Zone 3 Varieties

The best hydrangea species for zone 3 are Hydrangea arborescens, or smooth hydrangea, and Hydrangea paniculata, also known as panicle hydrangeas. Both of these species bloom on new wood, which makes protecting them from the harsh winter weather a breeze.

Hydrangea arborescens ‘Lime Rickey’

‘Lime Rickey’ has disc shaped flowers that are both large and beautiful. These flowers will start as a light green and fade into a darker green as the season progresses. Interestingly, compared to other varieties, their pollen is pink. This makes for a very beautiful summertime color display.

‘Lime Rickey’ will bloom regularly, and their flowers are known to come back season after season. This variety will grow to around five feet tall, and would be a good choice for a mass planting or hedge. Hardy in USDA zones 3-8

Hydrangea arborescens ‘White Dome’

The ‘White Dome’ smooth hydrangea is a large shrub, growing from four to six feet high as well as wide, making it a substantial addition to your gardens. ‘White dome’ is a white flowering variety with blooms that grow from six to ten inches.

These blossoms look like clouds floating on top of the hydrangea stems. The flowers are white and will turn pink as they age. This variety of hydrangea would make a gorgeous hedge, or would be well used as a back border of a perennial garden. Hardy in USDA zones 3-8.

Hydrangea paniculata ‘Little Lamb’

‘Little lamb’ has very unique flowers with small and delicate flower petals. There are a lot of tiny flowers that make up each flower head. They are tightly clustered together, creating the appearance of the fleece of a lamb jumping over the leaves of the shrub.

‘Little Lamb’ flowers will bloom white in the mid summer and may turn pink in the fall. This variety will grow four to six feet high and wide. Use this variety in cut flower gardens, in a mass planting, or in your perennial gardens. Hardy in USDA Zones 3-8.

Hydrangea paniculata ‘Little Lime’

‘Little lime’ is the dwarf variety of limelight. This dwarf version of the gardener’s favorite will grow from three to five feet tall. Just like “Limelight’ the flowers will be a fresh green that turn pink as the season gets closer to the fall.

This variety is known for its stronger steps, which will help keep flowers upright through the growing season. ‘Little Lime’ is a popular selection for containers, or as a hedge. Prune this ‘Little Lime’ in the early spring to encourage new flower buds to form. Hardy in USDA zones 3-9.

Growing in Zone 3

When growing in zone 3, there’s some important things to consider. Each step of the overall growth and care process will be a bit different due to the cooler climates. Let’s take a deeper look at when to plant, planning with lights, water, and overall care.

Planting

In zone three, the best time to plant is in the fall or the spring. First, you’ll want to find the right place to grow your new shrub. You’ll want to make sure the new hole is twice as large as the container space that it came from.

You’ll want to dig deeper than the original pot, but not more than a few inches because you don’t want to bury the plant itself.

Hydrangeas love moist, well draining soil. If you have clay soil, or sandy soil you will need to amend it with some organic material, such as compost. Once you have backfilled the soil around the newly planted shrub, water your until you notice a small puddle of water on the top of the soil. Once that puddle of water is absorbed, give it just a little bit more.

Light Requirements

Hydrangea arborescens, or the smooth hydrangeas, do best in partial sun with four to six hours of morning sunshine. Hydrangea paniculata is one of the few varieties that can take full sun and will be happy in six hours or more of sunlight.

Watering

Hydrangeas are water lovers and their leaves are known to wilt toward the ground when they are getting too much direct sun or during a summer heat wave.

Watering regularly, weekly or more often in the hot months, will help keep them from drying out. You may need to water daily while they are establishing themselves in your garden.

Do your best to avoid overhead watering. If you are watering by hand, keep the hose at the base of the plant. If water is left to sit on their leaves, you could run into problems with fungal diseases.

Pruning

When it comes to pruning, the panicle and smooth hydrangeas could not be easier to handle. These species bloom on new wood, meaning that they will not form their flower buds until springtime.

You may opt to prune in the fall after blooming has ended, or in the spring before any new growth has appeared.

Pruning new wood bloomers can go two ways: you can prune everything to the ground, or you can prune out most of the growth, and leave a few woody (or older) stems for support. The second option here would be very helpful with smooth hydrangeas.

Fertilizing

Hydrangeas benefit from an all purpose tree and shrub fertilizer a few times a year. It is recommended to fertilize in the spring and not to fertilize too late into the season to prevent any new growth from forming too late into the season.

If you notice that your hydrangea is failing to bloom, or that their blooms are weak – add some bone meal to the soil. Phosphorus is important for flower production, and bone meal contains a high amount.

Zone 3 Winter Care

In zone 3 it will be important to protect your hydrangeas over the winter.

If you choose to protect your plants, you can use stakes and chicken wire, but be sure to leave enough room between the wire and the plant to prevent rubbing. Use pine straw or dried oak leaves to insulate your plant. You can use anything that does not compact too easily.

The species you will likely be growing in zone 3, panicle or smooth hydrangea, are not at too much risk for winter damage because pruning is very flexible. If you choose not to protect your plants, you will likely be fine. If you notice any damage in the spring, prune it away as soon as you can.

Color Control

Hydrangea macrophylla and Hydrangea serrata are the species that have flowersthat are sensitive to your soil’s pH. Unfortunately for zone 3 gardeners, bigleaf hydrangeas are not cold hardy.

If you grow bigleaf hydrangeas as an annual in a container you can alter the color of your flowers by adding a soil acidifier, or aluminum sulfate, for blue flowers, or garden lime for pink flowers.