Hydrangea (hy-DRAN-jee-ah) is a climbing woody shrub belonging to the genus Hydrangea and from the Hydrangeaceae or the hydrangea family. It has over 75 flowering species and more than 600 cultivars available worldwide.
The genus name Hydrangea came from the Greek words “hydro,” meaning water, and “angos or angion,” which means a vessel, jar, or tub.
It references the plant’s shape and seed capsules, resembling an ancient water pitcher. The name also means “water vessel,” referencing the plant’s great love for humidity and water.
This deciduous shrub is native to Asia and regions of America, and its different species are widely grown and cultivated in Japan, China, Korea, Indonesia, North and South America, Africa, Europe, and the Himalayan mountains.
It also commonly grows in streambanks, ravines, moist wooded slopes, and bluff bases.
Hydrangea is well-known for its showy clusters of umbrella or round-shaped flowers in various colors, such as white, blue, pink, purple, green, or even red, with toothed or lobed green leaves.
Hydrangea is also known for its common name, Hortensia.
Its common name Hortensia was derived from the Latinised version of the French name Nicole-Reine Hortense Lepaute, honoring the famous French mathematician and astronomer.
In addition, there are 6 main Hydrangea types, namely:
- Hydrangea macrophylla – also known as Bigleaf, French Hydrangea, Mophead, or Lacecap Hydrangeas with attractive rounded blue or pink blooms, depending on the soil’s acidity.
- Hydrangea paniculata – also known as Panicle Hydrangea, with large conical or cone-shaped blooms in shades of pink.
- Hydrangea arborescens – also known as Smooth or Wild Hydrangea, with clusters of creamy-white or green flowers.
- Hydrangea quercifolia – also known as Oakleaf Hydrangea, resembles an oak tree with white to purplish-pink flowers.
- Hydrangea petiolaris – also known as Climbing Hydrangea, growing as a versatile vine with large, delicate white to greenish lace cap flowers.
- Hydrangea serrata – also known as Mountain Hydrangea, grows with clusters of delicate, small lace cap flowers.
Quick Facts On Hydrangea
- Family: Hydrangeaceae
- Light: Full Sun; Partial Shade
- Temperature: 50° to 60° degrees Fahrenheit
- Water: Regular Watering; Evenly Moist, Well-drained
- Fertilizer: All-purpose, balanced fertilizer
- Propagation: Cuttings
- Common Problems: Leaf spot, Drooping Leaves, Mildew, Rot, Aphids, Scale, Slugs
Hydrangea Care
How Big Does Hydrangea Grow?
Hydrangeas are fast-growing flowering plants that reach about 2′ feet or more of growth per year.
It has 3 growth forms, namely:
- Rounded
- Mounding
- Multi-stemmed
In general, hydrangeas may grow up to 15′ feet and 12′ feet wide, depending upon the variety, while small types may only reach 3′ feet tall and wide.
The Hydrangea macrophylla (Bigleaf or French hydrangea) reaches about 6′ to 10′ feet tall and wide.
In contrast, the Hydrangea paniculata (Panicle hydrangea) commonly grows 8′ to 15′ feet tall and 6′ to 12′ feet wide but may reach up to 20’t feet tall and wide if left unpruned.
The Hydrangea arborescens or Smooth hydrangea typically reaches around 3′ to 5′ feet tall and wide, while the Hydrangea quercifolia (Oakleaf hydrangea) reaches about 6′ to 8′ feet tall and wide under great growing conditions.
Moreover, the Hydrangea petiolaris (Climbing Hydrangea) are versatile vines that can grow 30′ to 40′ feet tall and 5′ to 6′ feet wide when grown upright but may reach up to 80′ feet long.
Lastly, Hydrangea serrata (Mountain Hydranga) typically grows about 2′ to 4′ feet tall and wide.
When Does Hydrangea Flower? Are The Flowers Fragrant?
Hydrangeas are prized for their unrivaled beauty as a cluster of colorful flowers, commonly called corymb. It comes in shades of white, green, pink, purple, pink, or red.
Its flowers also come in various bloom inflorescences, depending on the variety.
Most hydrangeas, especially Bigleaf Hydrangeas, feature corymb inflorescences or flower clusters that grow at the same level, but their flower stalks grow at different lengths.
Clusters of large and rounded flowers resembling pompoms or a mop’s head are also a notable feature of some hydrangea varieties.
In addition, some varieties produce delicate lace-cap or flat lacy flower heads, while others have conical flowerheads.
Additionally, the colors of hydrangea flowers, especially mountain or bigleaf hydrangeas, may be influenced to change colors to blue, purple, red, or pink.
Although it’s important to note that not all hydrangea types will change color, only the Bigleaf hydrangeas—especially Mophead and Lacecap varieties—and Hydrangea serrata can change colors based on the pH of the soil.
Generally speaking, you can change the color of your hydrangea flowers by manipulating or altering the soil acidity.
For lavender or blue hydrangea blooms, the soil’s pH level should be lower than 6.0.
If you prefer red or pink shades of blooms, the soil should be alkaline with a pH level above 7.0.
For a purple or a combination of colors (bluish to pink), the pH level should be between 6 and 7.
You may witness the breathtaking blooms of Hydrangea flowers with their aromatic or sweet fragrance, usually from mid-spring to late summer or early fall, providing long-lasting pop of colors.
What Are The Lighting Needs And Temperature Requirements?
Hydrangeas thrive in full sun with at least 6 hours or more of direct sunlight daily and prefer the morning sun because it’s less intense and generally cooler.
They are also shade-loving flowering plants, growing well in partial shade locations with about 2 to 6 hours of direct sunlight but only part of the day.
It’s best not to grow hydrangeas in locations with too much direct sunlight as it can cause serious problems, such as burned leaves and blooms.
If you notice your burnt leaves on your hydrangea plants or dropping flowers, it clearly indicates your hydrangea is getting too much sun.
Your hydrangeas also do best when planted in a north or east-facing location with an ideal temperature of about 50° to 60° degrees Fahrenheit.
In addition, Hydrangeas prefer dry climates with moderate to high humidity and enough moisture to keep the leaves from turning brown and becoming dry.
They also grow best in USDA Hardiness zones 5 to 9.
How And When To Water And Fertilize Hydrangea?
Hydrangeas need regular watering and consistent, reliable moisture throughout the growing season and when it’s actively flowering.
Deep water your hydrangeas at least once to twice weekly, especially in dry and hot conditions. But ensure not to let water stand or overwater your hydrangeas as they are prone to root rot.
It’s also important to remember that hydrangeas are fussy regarding the proper watering requirements.
Therefore, Underwatering and overwatering may cause the plant to produce fewer blooms or, worse, stunt your hydrangea’s growth.
For fertilizer application, it’s best to feed your hydrangeas with all-purpose balanced fertilizer or half-strength, water-soluble fertilizer every week while they are actively growing and blooming.
What Is The Best Soil For Hydrangea, And When Should You Transplant?
Hydrangeas grow best when planted in fertile, humus-rich soil with excellent drainage but can tolerate different soil types.
They also prefer moist soil rich in organic matter that is neutral to slightly acidic with a pH level of about 6.0 to 8.0
If the soil is heavy or is in poor condition, you may enrich and improve its quality by amending it with compost before planting.
Moreover, Hydrangeas are best repotted in spring.
Does Hydrangea Need Special Grooming Or Maintenance?
In general, hydrangeas are low-maintenance deciduous shrubs, but you may prune them to encourage the best flowering as they bloom on the previous year’s new growth.
You may also remove the dead stems and flowers to improve the hydrangea’s shape and structure.
Deadheading is also recommended to keep the blooms all season.
How To Propagate Hydrangea Plant?
Hydrangeas or hortensia plants can be propagated through stem cuttings.
Here’s how to do it:
- Take about 6″ to 8″ inches long of new growth stem (lighter green) without a flower in late fall or early winter.
- Cut the stem below a leaf node using sterile, sharp shears or pruners.
- Strip or remove the bottom leaves, but ensure a set of leaves are left on the stem (top leaves).
- Carefully cut the remaining leaves crosswise or half horizontally.
- Dip the stem cutting’s bottom in rooting hormone.
- Place the stem cutting’s end into a pot or container about 8″ to 10″ inches big with damp potting soil.
- Cover the pot or container with a plastic bag, cutting the top of it with tiny slivers to let the cuttings breathe.
- Place the pot or container with cuttings away from direct sunlight.
A root system will begin to develop in about 2 to 4 weeks, and you may transplant your hortensia cuttings afterward.
Hydrangea Plant Pests And Diseases
Hortensia plants are generally pest and disease-free, but many species of it are prone to the following pests:
- Aphids
- Black vine weevil
- Japanese beetles
- Spider mites
- Scales
- Slugs
You must also keep a lookout for diseases, such as:
- Botrytis blight
- Bacterial wilt
- Leaf spot
- Powdery mildew
- Root rot
- Yellow or brown leaf spotting
The best way to remedy these problems is to destroy the infected plants, but you may also use fungicides to treat most problems.
Ensure you’re following the product label’s instructions.
Hortensia plants are also susceptible to dropping leaves because of underwatering.
On the other hand, yellowing leaves will occur once the plant is overwatered.
If you also notice your hortensia leaves turning brown on the edges or tips, it’s most likely due to overfertilization.
Lastly, if you notice your hydrangea plant not blooming because of overfertilization, wrong time of pruning, and damage to buds.
Uses Of Hortensia Plant
Hortensia plants or hydrangeas are well-known deciduous shrubs widely grown and cultivated for their showy flowers.
They make excellent blooming indoor houseplants or potted plants.
Hydrangeas are also a great decorative for shrub borders, group plantings, landscapes, and gardens, providing a breathtaking mass of color.
They can also be planted as groundcovers, trained on a fence or a trellis, and grown as an excellent backdrop or filler for smaller plants.
In addition, their showy clusters of lovely blooms are excellent as cut flowers and for vase display.