How Big Will Hydrangeas Grow When Fully Mature? (2024)

Often, when you think of a hydrangea, your favorite species will come to mind, which is different for each of us. Did you know that each of the most popular species of hydrangeas grows to different heights?

Hydrangeas have many uses in the garden, from container plantings to privacy screens and hedges. The size of your space as well as the mature size of the variety you choose is very important to the overall health and success of your plantings.

So, how big do hydrangeas get? Which one should you choose for your yard? Let’s dig in and find out.

The Long Answer

Many factors contribute to the size of your hydrangeas at maturity. The variety of hydrangeas you have will be the best way to determine their size. Sizes can vary greatly not only between species but also within species. There are many compact varieties that will come in at the lower end of the height chart.

Other elements will factor into the size of your hydrangeas. Ensuring they receive the proper sunlight, are getting enough water, grow in the right climate, are planted in favorable soil conditions, and are pruned can be considerations for how big they grow. Let’s take a look at each factor you’ll need to consider when growing hydrangeas.

Sizing Chart by Species

As mentioned above, the species of hydrangea you have in your garden is the best-determining factor of how big it will get. Here is a chart with each of the six hydrangea species and their general size for quick reference.

Hydrangea anomala

The climbing hydrangea is a stunning variety of hydrangea that works just as well climbing up an arbor or as a creeping ground cover under a large tree. This vine will produce large white lacecap flowers in the summertime.

Try training a climbing hydrangea up a trellis, a tree trunk, or along a fence. This species will do best climbing up something that is textured as opposed to smooth, like a vinyl trellis. This vine can reach heights of 40 and even 50 feet!

Hydrangea petiolaris

	botanical name Hydrangea anomala ssp. Petiolaris
	sun requirements Partial Shade to Shade
	height 30-40 feet tall, 5-6 feet wide
	hardiness zones 4-9

This is the classic climbing hydrangea that has caused all of the other varieties to gain popularity. The white flowers on this climbing vine are foamy and abundant. These flowers can reach up to 8 inches in diameter. In the winter, the bark of this vine is red and slightly peeling, adding beauty to an otherwise barren garden.

Hydrangea arborescens

The smooth hydrangea is native to North America, making it one of the easiest to grow. Their large flowers have been known to weigh down the branches a bit in some varieties, such as ‘Annabelle.’

However, there have been many improvements made with new varieties that claim to defeat the drooping. The flowers of the smooth hydrangea are white or green and will last throughout the summer.

In general, smooth hydrangeas will grow a bit wider than they do tall. This characteristic makes it a good choice for a low-growing border or a mass planting along a woodland edge. This species also grows very nicely in large containers.

Hydrangea ‘Incrediball’

	botanical name Hydrangea arborescens ‘Incrediball’
	sun requirements Full sun to Partial sun
	height 4-5 feet tall and 4-5 feet wide
	hardiness zones 3-8

‘Incrediball’ is an improved species of smooth hydrangea. The stems are sturdy enough to support the weight of the massive flowers, which can reach up to 12 inches across. These flowers open in a fresh shade of green and mature to a creamy white as the season progresses.

Hydrangea macrophylla

This species is most known for its blue blossoms. While the blue flowers on the bigleaf, or French hydrangea, are stunning, there are also species with pink, purple, or white flowers.

While all hydrangeas thrive in acidic soil, the acidity of the soil is what will control the color of your flowers. The more acidic your soil, the bluer or purple your blossoms will be. The sweeter or more alkaline your soil is, the pinker the flowers will be. This holds true unless you have a species with white blooms; these flowers will remain white no matter the soil pH.

The size of the bigleaf hydrangeas makes the shrub very versatile. Growing to about 6 feet tall, you can easily use this species as a foundation planting, a small hedge, or throughout a partially shaded garden bed.

Hydrangea ‘Pia’

	botanical name Hydrangea macrophylla ‘Pia’
	sun requirements Partial Sun
	height 2-3 feet tall and 2-3 feet wide
	hardiness zones 5-9

‘Pia’ is a very pretty pink flowered bigleaf hydrangea. On the smaller side, ‘Pia’ can be tucked into many spaces in your garden and is especially beautiful in containers.

The 4-inch blossoms on this cultivar will remain pink despite the pH of your soil, but you may notice variations of the exact shade of pink.

Hydrangea paniculata

The largest shrub of the species is also the sun-loving species. These large hydrangeas form large cone flowers that tend to be multi-colored depending on the time of the season. Most of these blossoms will open white and mature to shades of green, pink, or red.

Hydrangea paniculata has varieties that will reach up to 15 feet, while most of them max out around 8 feet tall. Panicles are great when used for hedges or privacy screens. Just keep in mind that these shrubs are not evergreen and they will not have leaves over the winter.

Hydrangea ‘Fire Light’

	botanical name Hydrangea paniculata ‘Fire Light’
	sun requirements Full sun to Partial sun
	height 6-8 feet tall and 6-8 feet wide
	hardiness zones 3-8

Another gorgeous cultivar, ‘Fire Light,’ is loaded with large flowers that will begin their journey as a creamy white and age to light pink, finally resting in a vibrant shade of raspberry. The strong stems will support these bright flowers all season long.

Hydrangea quercifolia

Hydrangea quercifolia, also known as the oakleaf hydrangea, has the most interesting foliage of all the species. Their leaves have a similar shape to that of the leaves of an oak tree.

They often take on a lovely red color in the fall, adding to their beauty. The flowers are long and conical and are often in shades of white, pink, or red.

This species can reach heights of up to 8 feet. They are lovely when used on a woodland edge.

Hydrangea ‘Pee Wee’

	botanical name Hydrangea quercifolia ‘ Pee Wee’
	sun requirements Full sun to Partial sun
	height 4-5 feet tall and 4-5 feet wide
	hardiness zones 5-9

‘Pee Wee’ is the perfect oakleaf hydrangea for smaller gardens, coming in at just about 5 feet tall and wide. The upright cone-shaped flowers bloom as white and mature into a rosy shade of pink, while the leaves are a fresh green until autumn when they take on a hue of wine. ‘Pee wee’ blooms in the early summer and will last into the fall.

Hydrangea serrata

This species of hydrangea is a subspecies of Hydrangea macrophylla. The main differences are that the mountain hydrangea, Hydrangea serrata, is a little bit smaller than the bigleaf, and the flowers they produce are of the lacecap variety.

It is not quite clear if these flowers are sensitive to the pH of your soil as the bigleaf species is, but you may have some success playing around with your soil if you want.

This species will grow to about 4 feet tall. This petite size makes them a great addition to your perennial gardens or in the middle of a foundation garden.

Hydrangea ‘Bluebird’

	botanical name Hydrangea serrata ‘Bluebird’
	sun requirements Full sun to partial sun
	height 3-4 feet tall and 3-4 feet wide
	hardiness zones 6-9

As the name implies, this mountain hydrangea is covered with pretty blue lacecap flowers from summer all the way into the fall. The leaves of this variety will turn a bright red when autumn arrives.