In Georgia, bigleaf hydrangeas, Hydrangea macrophylla, sometimes known as French, Japanese, or snowball hydrangeas, are grown both as landscape and florist plants. Bigleaf hydrangeas are frequently bought as gift plants from florists and can be transplanted to the landscape for yearly blooms. By modifying the soil pH, homeowners can alter the color of flowers from pink to blue or from blue to pink.
Two Main Groups
In the nursery industry, bigleaf hydrangeas come in more than 500 different cultivars. They can be split into two main categories: hortensias, which have huge flower clusters resembling snowballs, and lacecapes, which often have flowers with fairly flat tops, fertile blooms in the center, and showier sterile flowers on the periphery.
Location
Bigleaf hydrangea prefers moist, well-drained soil, morning light, and afternoon shade. Don’t plant it in exposed, hot, dry areas. Winter and late spring can cause cold damage to the buds, so be ready to offer some winter protection by wrapping the plant in an old sheet, blanket, or cardboard box when the temperature drops below freezing. Additional effective cold protection is offered by a cylinder of chicken wire surrounded by leaves.
Bigleaf hydrangea is a great patio plant that is simple to cultivate in containers. The ability to bring the plant indoors on a chilly night is another benefit of growing it in a container.
Planting
Prepare the soil over a large area if at all possible. Apply 50 pounds of decomposed organic material per 10 square feet and thoroughly work it with a tiller or shovel into the top 8 to 12 inches of soil. Organic matter keeps nutrients and water in the soil and protects plants from stress caused by changes in soil moisture from wet to dry.
Before the plant is established, don’t fertilize (4 to 8 weeks after transplanting). Since Georgia’s soils tend to be acidic, the first blossom color will probably be blue.
After transplanting, make sure the root ball’s top is flush with the soil’s surface and give it a good drink of water. To retain moisture and manage weeds, add 3 to 5 inches of an organic mulch to the soil’s surface, such as pine straw, pine bark, or fallen leaves.
Fertilization and Watering
Throughout the growing season, bigleaf hydrangea responds to many sparing fertilizer applications. It is advised to apply a general-purpose fertilizer, such as 8-8-8 or 10-10-10, at a rate of 1 pound (2 cups) per 100 square feet in the months of March, May, and July. When fertilizing, it is not required to remove the mulch; however, watering soon after application will help the fertilizer dissolve and go into the soil.
Bigleaf hydrangea is a water-hungry plant that does best in landscape zones with moderate water requirements. When the plant starts to wilt in the absence of rain, water it. Avoiding plant stress during the spring, when the blooms are developing, is especially crucial.
Flower Color
According to research, the presence or absence of aluminum compounds in the flowers is the real cause of color variation. The color is blue if aluminum is present in the plant. If it’s absent or only minimally present, the blooms are pink, and if it’s there, the color is “in between.”
Through influencing the amount of aluminum in the soil, soil pH indirectly influences flower color. Aluminum is typically more accessible to the roots in soil that is acidic (pH 5.5 or lower). Alkalinity (pH 7.0 or above) in the soil reduces aluminum availability and increases the pinkness of the blooms.
Distribute 1/2 cup of wettable sulfur per 10 square feet and water it in to gradually turn pink flowers blue. Spread one cup of dolomitic lime per 10 square feet and soak it into the soil to turn the flowers pink. The effects of this treatment on flower color could not be visible for a year.
Through liquid soil drenches, you can change the color of your flowers more quickly and easily. In March, April, and May, saturate the soil around the plant with 1 tablespoon of alum (aluminum sulfate) dissolved in 1 gallon of water to make the blossoms blue, or perhaps more blue. In March, April, and May, soak the soil surrounding the plant with a solution of 1 tablespoon of hydrated lime in 1 gallon of water to turn the blossoms pink. Avoid getting the mixture on the leaves to prevent foliar damage.
Failure to Flower
Bigleaf hydrangeas can have problems with flowering failure. This may be brought on by winter damage to the flower buds, overly-shady plant growth, an excess of nitrogen fertilizer, or untimely pruning. Pruning throughout the late summer, fall, and winter will eliminate prospective blossoms since bigleaf hydrangeas develop their flower buds in the late summer for the next year.
Pruning
When the bigleaf hydrangea’s blossoms start to fade, prune it. To promote branching and fullness, remove blossom heads and head back other shoots as appropriate. Avoid pruning after August 1 since flower buds for the following season will start to grow in late summer.
After a difficult winter, it may be necessary to prune plants to remove damaged foliage. The removal of winter-damaged leaf is healthier for the health of the plant and its aesthetically pleasing appearance, even though it will promote vegetative growth at the expense of flowering.
Propagation
Softwood cuttings collected in the early summer can be used to multiply bigleaf hydrangeas. Choose terminal cuttings from shoots that are not in bloom. A minimum of three leaves and a length of 3 to 5 inches should be present on each cutting. Make a little angle cut at the node (where the leaves are joined), then dip the cut end in a rooting hormone and plant it in a moist growing medium. To prevent wilting and dehydration, propagators frequently cut off the top half of each leaf. While the cuttings are rooting, keep them wet and in a shaded environment.
Layering is another method of bigleaf hydrangea propagation in the landscape. This is accomplished by excavating a trench close to the plant and bending a branch downward into the trench. At the point where the limb touches the ground, use a knife to carefully remove a narrow band of outer bark that is about an inch broad. After that, bury the limb in dirt, leaving 6 to 12 inches of the growth at the tip exposed. The new plant should be ready for transplantation the following winter if layering is done in the summer.
Early spring is a good time to separate clumps of mature, older hydrangeas with a shovel. A cluster that has been there for a while can produce many plants.
For More Information
On hydrangeas, there are several top-notch books accessible from publishers and online. Dr. Michael Dirr, a former professor at the University of Georgia, is the author of the book Hydrangeas for American Gardens. Both online and in bookstores, it is widely accessible. Additionally, the U.S. National Arboretum offers a fantastic online resource for choosing and growing hydrangeas. To learn more, visit www.usna.usda.gov/Gardens/faqs/hydrangeafaq2.html.
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Which side of the house should hydrangeas be planted on?
Bushes called hydrangeas bear white, pink, or blue blooms. These are small flowers that grow in voluminous bloom clusters. These bushes will typically reach a height of four to six feet and bear flowers that can range in length from six to eighteen inches. These shrubs thrive best in damp soil and are extremely cold hardy. These shrubs prefer some shade and cannot stand full sun or complete darkness. H. anomala, a climbing variation of hydrangeas, is also available. This type can either be let to grow along the side of a structure or planted on a trellis on the north side of the house. It has the capacity to grow as tall as 80 feet. Hydrangeas do well when planted close to small evergreens or woody shrubs because they also do well in woodland regions.
- No matter where in the nation you reside, the north side of your house receives little natural light.
- Hydrangeas do well when planted close to small evergreens or woody shrubs because they also do well in woodland regions.
What is the ideal location for hydrangea planting?
Plant hydrangeas close to a water source in an area with lots of light. Choose a location in the South where there is morning sun and afternoon shade. Hydrangeas can tolerate full-day sun in the north.
Do hydrangeas thrive in Georgia?
Georgia has experienced perfect weather this year, and hydrangeas are enthusiastically flowering. At Gibbs Gardens, there are more than 1,000 blooms to see, including native and cultivated selections.
In Georgia, when may I plant hydrangeas?
Hydrangeas have huge bloom heads and exude an old-fashioned elegance. How to plant and take care of beautiful floral bushes is explained in our hydrangea growing guide. Additionally, learn the answers to frequently asked questions like “why aren’t my hydrangeas blossoming this year?”
About Hydrangeas
These elegant plants are simple to grow, withstand nearly any sort of soil, and produce an abundance of blossoms that are unmatched in the world of shrubs for their stunning flowers. Clear blue, vivid pink, frosty white, lavender, and rose blossoms sometimes grow on the same plant, enticing us with their colors.
From container gardens to shrub borders to group plantings, hydrangeas are great for a variety of garden locations. Breeders seem to give us more possibilities every year, and gardeners have countless expectations for bloom size and color. Varieties abound. Pay attention to the species listed below to get an idea of how your hydrangea will develop as some require different maintenance. The joys you experience will be enhanced when you know what to expect.
Enjoy this tribute to hydrangea beauty and read our guide below to discover how to grow hydrangeas.
Where to Plant Hydrangeas
- The majority of hydrangeas like fertile, moisture-rich soils that drain well. Compost can help improve bad soil.
- Hydrangeas typically prefer some sun. In an ideal world, they would receive full sun in the morning and then some afternoon shade to avoid the intense midday sun. The Bigleaf Hydrangea (H. macrophylla), with its huge, prone-to-wilting leaves, is a prime example of this. Some kinds can withstand more direct sunlight.
- Depending on the kind, place hydrangeas anywhere between 3 and 10 feet apart. Plants should always be spaced according to their anticipated mature size!
When to Plant Hydrangeas
- The optimum season to plant hydrangeas is in the fall, followed by spring. The cooler shoulder seasons are the ideal times to plant shrubs because they will have plenty of time to build a strong root system before the intense heat of summer or the bitter cold of winter.
- In the early morning or late afternoon, plant the shrubs. The plant is less prone to experience heat stress from direct sunshine because it is typically cooler.
How to Plant Hydrangeas
- Gently remove the hydrangea from its container and examine the root ball. Snip off any rotten or dead sections, and if the plant is very root-bound, pry the roots free.
- Make a hole that is two to three times as big and as deep as the root ball. The top of the planting hole should be level with the base of the plant, which is where the stem joins the earth.
- After placing the plant in the hole, add enough soil to fill it halfway. generously hydrate. Fill the remaining space in the hole with soil once the water has been absorbed.
- once more, thoroughly rinse.
How to Grow Hydrangeas from Cuttings
Cuttings of hydrangeas can be easily grown. They easily take root, and the process is a wonderful teaching tool for propagation. This is how you do it:
- Find a branch on a mature hydrangea that is fresh growth and has not flowered. In comparison to older growth, new growth will appear lighter in color, and the stem won’t be as firm.
- Make a horizontal incision 4 to 5 inches down from the branch’s tip. Make sure your cutting has at least three to four pairs of leaves.
- Trim the cutting’s lowest pair of leaves so that they are flush with the stem. If you can afford to remove more than one pair of leaves, do so. Roots develop more readily from these leaf nodes. But make sure to leave at least two pairs of leaves at the cutting’s tip.
- Remove the tip half of any leaves that are still pretty large by cutting them in half. This keeps the leaves from slamming into the sides of the plastic bag you’ll later use to cover the cutting (to keep the humidity up).
- (Optional) Sprinkle rooting hormone and a plant antifungal powder on the stem’s leafless area (both available at a local hardware or garden store). This will promote roots and deter decay.
- Prepare a small pot and put moistened potting soil inside. The cutting should be planted in the ground, buried down to the first remaining pair of leaves. Lightly water the area surrounding the stem to close any air spaces.
- Wrap a plastic bag loosely around the entire pot. To prevent the cutting’s leaves from rotting, make sure the bag is not touching them. The bag can be supported by chopsticks or other such objects to keep it off the leaves.
- Put the pot in a warm location that is protected from the wind and sun.
- Only rewater your cutting after the top layer of soil is dry after checking on it every few days to make sure it isn’t decaying. In a few weeks, hopefully, the cutting will start to root! If you feel resistance when you gently tug on the cutting, roots have grown.
Watering
- Make sure hydrangeas get enough water for the first year or two after planting and throughout any droughts.
- Over the course of the growing season, water at a rate of 1 inch per week. Three times a week of heavy watering is preferable to shallow watering. Root growth is promoted by this.
- All varieties of hydrangeas benefit from constant moisture, but bigleaf and smooth hydrangeas need more water.
- If the soil is too dry, the leaves will wilt, and there won’t be enough moisture for the flowers to bloom.
- To water thoroughly while keeping moisture off the flowers and leaves, use a soaker hose.
- The best time to water hydrangeas is in the morning to protect them from disease and get them ready for the heat of the day.
- Under your hydrangeas, spread organic mulch to help keep the soil cool and moist, gradually add nutrients, and enhance soil texture.
Fertilizing
You might not need to fertilize hydrangeas if your soil is rich. When fertilizer is applied in excess, blossoms are sacrificed in favor of green growth. A soil test is the most effective tool for determining your fertility requirements.
Apply fertilizer according to the type of hydrangeas you have. Every variety has varied requirements and will profit from applying fertilizer at various times.
- Several mild fertilizer applications in March, May, and June are beneficial for bigleaf hydrangeas.
- Two applications in April and June work best for oakleaf and panicle hydrangeas.
- The only time smooth hydrangea plants require fertilizing is in the late winter.
Winter Protection
- Cover plants with bark mulch, leaves, pine needles, or straw in the fall, at least 18 inches deep. If at all feasible, create cages out of chicken wire or snow fencing and cover the entire plant, including the tip, with the cages. (Avoid using maple leaves; they have a tendency to mat after becoming wet and may suffocate the plant.)
How to Prune a Hydrangea
Many of the queries from readers concern hydrangea trimming. It makes sense that it’s unclear because it relies on the hydrangea kind. Fortunately, identifying which type you have makes determining the best pruning strategy simple. Discover the fundamentals below, then read more about pruning different varieties of hydrangea here.
Pruning Common Hydrangeas
The Bigleaf cultivar of Hydrangea macrophylla is the most popular garden hydrangea shrub. (For more, see below.)
Hydrangeas with large leaves, such as Bigleaf (H. macrophylla), Oakleaf (H. quercifolia), Mountain (H. serrata), and Climbing (H. anomala subsp. petiolaris), are pruned AFTER the summer blooms have passed. On stems from the previous season, these kinds bloom (“old wood).
- Avoid pruning after August 1 since flower buds actually grow in the late summer and bloom the next season.
- Dead wood should only be removed in the fall or very early spring.
- To stimulate branching and fullness, trim one or two of the oldest stems by cutting them all the way to the ground.
- Pruning the stems all the way to the base is necessary if the plant is old, neglected, or injured. For the following season, you’ll lose the flowers, but you’ll also revive the plant for subsequent ones.
- The huge Mopheads should not be deadheaded (faded flowers removed); instead, you should leave them over the winter and trim them back in the early spring (to the first healthy pair of buds). Deadheading Lacecaps is OK; simply trim down to the second set of leaves below the bloom head.
- Avoid pruning unless it is absolutely required while growing H. macrophylla (and H. serrata) cultivars in Zones 4 and 5, and then only after blooming. If not, merely remove dead stems in the spring.
Pruning Other Hydrangeas
Hydrangeas called Panicle (H. paniculata) and Smooth (H. arborescens) are clipped BEFORE flower buds develop. On stems from the current season, these kinds blossom (“new wood).
- When the plant is dormant in the late winter, prune. The plant will therefore grow new buds in the spring that will result in blossoms even if the winter kills the buds.
- In general, avoid pruning to “shape the bush” and just remove dead branches.