How to Plant and Care for a Hydrangea in a Pot
Updated: 11 Nov, 2023
Hydrangeas, with their stunning blooms and versatile colors, make a delightful addition to any garden or patio, and cultivating them in pots offers a convenient solution for limited space or changing seasonal arrangements. Begin by selecting a large container with proper drainage to ensure healthy root development. Choose a potting mix rich in organic matter to provide the necessary nutrients. Hydrangeas thrive in well-draining soil with a slightly acidic to neutral pH. Select a suitable hydrangea variety based on your climate, considering factors like sunlight and temperature.
When planting, maintain the original soil level and water thoroughly. Regular watering is crucial, especially during hot weather, but be cautious not to overwater and cause root rot. Fertilize with a balanced, water-soluble fertilizer during the growing season. Pruning is essential for shaping and removing dead wood, promoting vigorous growth and abundant blooms. Protect the plants from harsh afternoon sun and ensure adequate winter protection in colder climates. With proper care, potted hydrangeas can flourish, providing a burst of color and elegance to your outdoor space.
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|1-6 feet tall, 1-6 feet wide
|Moist but well-drained
|Red, pink, green, blue, purple, white
|3-9 (USDA), depending on variety
|Cultivars (no native range)
|Toxic to humans and pets Hydrangea
Caring for potted hydrangeas closely mirrors the care provided to hydrangeas in a garden setting, with the notable difference being the increased demand for watering and fertilization.
Hydrangeas thrive in full sun, dappled sun, or partial shade, with variations in sun tolerance among different types. Mountain, smooth, panicle, and bigleaf hydrangeas flourish with four to six hours of daily sun, while panicle hydrangeas tolerate six or more hours. Morning sun is generally preferable, especially in warmer climates. When situating a large hydrangea, consider its weight when filled with soil; position it in the appropriate light conditions before filling, unless you have a caddy for relocation.
Opt for a lightweight, high-quality potting mix (not soilless seed starting mix) and blend four parts potting mix with one part compost. Adjusting the soil acidity in potted hydrangeas can be challenging, so it’s advisable to choose a hydrangea variety with the desired color rather than attempting to amend the pH.
Regular watering is crucial for potted hydrangeas due to their rapid soil drying compared to landscape hydrangeas. Check the soil daily, and when the top inch feels dry, water the entire soil until it drains through the holes. In hot weather, hydrangeas may require watering twice a day, with increased water needs based on sun exposure.
- Temperature and Humidity:
Like their counterparts in the landscape, hydrangeas in containers are sensitive to temperature extremes. Choose a protected location, preferably north- or east-facing, to shield them from the harsh summer heat and severe winter conditions. While hydrangeas tolerate moderate to high humidity, they struggle in dry, hot climates.
Potted hydrangeas, due to more frequent watering, necessitate regular fertilization. Use a granular slow-release fertilizer for flowering shrubs or, for blue-flowered hydrangeas, one designed for acid-loving plants. Apply in spring as the plant breaks dormancy, keeping the fertilizer away from branches. Monthly fertilization is advisable, with cessation in late summer to protect new growth from potential cold damage with the onset of the first frost.
Types of Hydrangeas
Hydrangeas are popular ornamental plants known for their large, showy blooms. There are several types of hydrangeas, each with its own unique characteristics. Here are some of the most common types:
- Bigleaf Hydrangea (Hydrangea macrophylla):
Known for its large, globe-like flowers.
Flower color can be influenced by soil pH, with acidic soils producing blue flowers and alkaline soils producing pink flowers.
Varieties include mophead hydrangeas (rounded flower clusters) and lacecap hydrangeas (flatter flower clusters with small, fertile flowers surrounded by larger, sterile ones).
- Panicle Hydrangea (Hydrangea paniculata):
Typically has cone-shaped flower clusters.
Tends to be more sun-tolerant than some other hydrangea types.
Flowers often start off white and may turn pink as they age.
- Smooth Hydrangea (Hydrangea arborescens):
Known for its round, white flower clusters.
Popular cultivar includes ‘Annabelle,’ which has large, globe-like blooms.
- Oakleaf Hydrangea (Hydrangea quercifolia):
Named for its leaves, which resemble those of oak trees.
Conical flower clusters and attractive fall foliage.
Tends to have a more open, loose growth habit.
- Mountain Hydrangea (Hydrangea serrata):
Similar to bigleaf hydrangea but often more compact.
Lacecap or mophead flower clusters.
Varieties may have different flower colors and sizes.
- Climbing Hydrangea (Hydrangea anomala petiolaris):
A climbing or sprawling hydrangea variety.
Adheres to walls and structures, producing flattened clusters of white flowers.
- PeeGee Hydrangea (Hydrangea paniculata ‘Grandiflora’):
A specific cultivar of panicle hydrangea.
Large, cone-shaped flower clusters that can turn pinkish in the fall.
Pruned into a tree form in some cases.
- Endless Summer Hydrangea:
A brand that includes varieties of bigleaf hydrangea known for their ability to bloom on both old and new wood, extending the flowering season.
It’s important to note that the characteristics and growing conditions can vary among different hydrangea species and cultivars. When choosing hydrangeas for your garden, consider factors such as flower color, size, and the specific needs of the chosen variety in terms of sunlight, soil, and water.
Propagation of container-friendly hydrangea cultivars is restricted as many of them are trademarked or patented, preventing any unauthorized reproduction.
Potting and Repotting Hydrangea
Select a container with a diameter of at least 16 to 24 inches, ensuring it accommodates the hydrangea’s root ball. Ensure the pot has ample drainage holes; although terracotta and ceramic containers are aesthetically pleasing, they may crack in winter.
To secure the soil, line the container bottom with a fine screen mesh. Add a layer of potting mix and compost, enough for the hydrangea’s root ball to rest slightly below the container rim. Remove the plant from its nursery pot and position it in the container. Surround the roots with soil, tamping it down as you progress. Water thoroughly and mulch the soil to retain moisture.
Depending on growth, repot the hydrangea into a larger container every three to five years when roots reach the container sides and growth slows.
Even if your potted hydrangea belongs to a winter-hardy variety for your zone, winterizing is likely necessary. Merely relocating the container to a spot shielded from harsh winter winds might not suffice. However, directly moving the plant indoors is not a viable option since the hydrangea requires its natural winter dormancy to maintain its rhythm.
The roots, being exposed in a container, are particularly susceptible to cold, necessitating insulation. For smaller pots, you can bury the container in the soil before it freezes. Alternatively, create an insulation silo by placing the container in a larger one filled with mulch or straw. Another option is wrapping the container with multiple layers of bubble wrap or burlap.
Note that terra cotta containers may be prone to cracking during freeze-and-thaw cycles.
Common Pests and Plant Diseases
Potted hydrangeas face the same pest challenges as their counterparts in the landscape, contending with issues like aphids, black vine weevils, Japanese beetles, and spider mites. Insecticidal soaps are effective for addressing minor infestations.
Additionally, hydrangeas are prone to various plant diseases, including botrytis blight, powdery mildew, Cercospora leaf spot, and viruses causing yellow or brown leaf spotting. Fungal diseases are more likely in confined, crowded spaces with inadequate air circulation, especially when hydrangeas are positioned too closely to other plants. To mitigate these risks, refrain from overhead watering, opting to water at the base instead. This practice prevents the persistence of wet foliage, which can contribute to the spread of fungal diseases.
How to Get Potted Hydrangea to Bloom
The absence of blooms in a hydrangea is typically attributed to insufficient sunlight. Excessive shade can diminish flowering. Consider relocating your plant to a sunnier location, compensating for increased evaporation with more frequent watering as required.
Florist hydrangeas, the petite potted mophead hydrangeas acquired in full bloom, often do not re-bloom. These plants are coerced into flowering for brief, showy appearances or as gifts. They are not intended for extended cultivation, either in containers or in the garden.
Can Hydrangeas Be Grown in Pots?
Hydrangeas adapt well to container gardening, adding a burst of color and elegance to your patio or balcony. Choose a suitable hydrangea variety and provide the right conditions for successful pot cultivation.
What Type of Pot is Best for Hydrangeas?
Opt for a large, well-draining container to accommodate hydrangea root systems. Ensure the pot has drainage holes to prevent waterlogging. Select a lightweight material like plastic or fiberglass to make moving the container easier.
How Often Should I Water Potted Hydrangeas?
Potted hydrangeas need frequent watering, as containers dry out faster than garden soil. Check the top inch of soil daily, and when it feels dry, water the plant thoroughly. In warmer climates, hydrangeas may require watering twice a day during peak summer.
What Light Conditions Do Hydrangeas Prefer in Pots?
Hydrangeas thrive in partial shade, receiving four to six hours of sunlight per day. Morning sun is generally better, especially in warmer regions. However, the specific light requirements may vary based on the hydrangea variety you choose.
Can I Change the Flower Color of Potted Hydrangeas?
Altering the flower color of potted hydrangeas is tricky. Unlike in the landscape, adjusting soil pH in containers requires precise measurements. It’s often easier to choose a hydrangea variety that naturally produces the desired flower color.
How Do I Fertilize Hydrangeas in Pots?
Fertilize potted hydrangeas with a balanced, slow-release fertilizer for flowering shrubs. Apply it in spring as the plant breaks dormancy, and continue monthly feedings until late summer. Avoid fertilizing in late summer to protect new growth from cold damage.
Can Hydrangeas in Pots Tolerate Extreme Temperatures?
Hydrangeas in pots are sensitive to temperature extremes. Place the containers in a protected spot, preferably north- or east-facing, to shield them from scorching summers and harsh winters. This prevents premature budding during warm spells.
Growing and caring for hydrangeas in pots can be a rewarding venture, bringing the beauty of these versatile plants to smaller outdoor spaces. By selecting the right container, ensuring proper watering, providing suitable light conditions, and choosing the appropriate hydrangea variety, you can enjoy vibrant blooms and lush foliage on your patio or balcony.
Remember the importance of regular watering, especially in containers where soil tends to dry out quickly. The choice of a well-draining potting mix, suitable fertilization, and mindful consideration of temperature extremes contribute to the overall health of your potted hydrangeas.