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 moved 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.
Associate in public service and coordinator of the state’s master gardening program; consumer ornaments
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When should I fertilize my hydrangeas?
In order to give your hydrangeas an early-season boost, you should typically fertilize them in the spring right before they start to leaf out. During July’s growing season, fertilize them a second time. Two applications of the fast-release fertilizers are necessary in the summer.
The ideal fertilizer for hydrangeas is what?
When purchasing fertilizer, check the labels to see how much nitrogen (N), phosphate (P), and potassium are present (K). A general-purpose, balanced fertilizer such a 10-10-10 N-P-K or 12-4-8 N-P-K is typically best for hydrangeas. Consider using a fertilizer with additional phosphorus if you want your hydrangea blossoms to be bigger and more numerous.
Since phosphorus is the middle element, fertilizer with the formula 10-20-10 will do. Choose a slow-release granular fertilizer with the designation “bloom boost” if you’re looking into it because it might also include more phosphorus.
When is it too late to fertilize hydrangeas?
Fertilizing hydrangeas once or twice in the summer is optimal for their growth. Despite the fact that some experts advise using specialized fertilizer blends to achieve the best results, hydrangeas thrive when given a more casual approach.
It is possible to use organic matter or chemical fertilizers successfully. This would be a fantastic first line of defense because putting manure and/or compost organically around the roots yields outstanding effects and also improves the soil’s quality. For optimal impact, organic soil improvements can also be paired with a dose of chemical fertilizer.
The simplest method, if chemical fertilizers are employed, is probably to apply a slow-release, balanced fertilizer once a year. The market is flooded with slow-release fertilizers. If you can locate a fertilizer made for trees and shrubs, it would be effective on hydrangeas. In order for the fertilizer to release efficiently when Osmocote is applied, the granules MUST BE covered with soil.
Slow-release fertilization is by no means the only method for hydrangeas, though. If used twice over the summer, a less expensive fast-releasing fertilizer such a 10-10-10 will perform just as well. A soil sample should be taken and the fertilizer and trace elements should be matched to your soil’s requirements if you want a fertilizing regimen that is personalized to your particular circumstances.
Fertilize no later than August. Hydrangeas start preparing for dormancy in the fall. By fertilizing now, you can encourage sensitive new growth that won’t be able to weather the winter. A late May application and another in July might be appropriate in the South. Northerner regions might want to fertilize just once in June or July.
The size and root system of the plant will determine how much chemical fertilizer is utilized per plant. If growing hydrangeas in a container, use less fertilizer. More harm can result from overfertilization than from underfertilization. When too much fertilizer is used, it can cause “fertilizer burn,” which damages or even kills the hydrangea by drying out the roots. To be on the safe side, use less fertilizer than you think is necessary. The first indicator of damaged roots is frequently leaves that seem charred. In severe cases of overfertilization, the plant may simply wilt and die.
Knowing that a very small plant will require between 1/8 and 1/4 cup of fertilizer when it is planted in the ground may be useful if you are new to growing plants. Apply a fertilizer with caution that won’t burn the roots when fertilizing hydrangeas in pots (such as a slow release or a liquid fertilizer). Two to three cups should be distributed around the drip line of the branches of a very large shrub planted in the ground (not next to the trunk). Please read the fertilizer’s instructions carefully before using it because this is only a very rough estimate.
For both plants in pots and plants in the ground, liquid fertilizer should be applied once a month if it is being utilized.
If a plant appears sick or wilted, never fertilize it with a chemical fertilizer. A plant will only experience more stress if the cause of its difficulties is a disease or a root issue. Prior to putting in fertilizer, try to solve the issue.
Do hydrangeas respond well to Miracle Grow?
There is no need to buy expensive plant food. This cost-effective alternative has a 15-30-15 N-P-K composition that encourages more flowers per shrub and colorful flower heads. Including hydrangeas, this all-purpose blossom enhancer can be applied to a large selection of permanent and annual blooming plants.
It offers a variety of minerals, such as iron, copper, and boron, to complement typical dietary deficits. For the biggest, brightest blooms and healthiest plants, the water-soluble formulation should be applied every 7 to 10 days throughout the growing season.
- Water-soluble fertilizer, type
- Ratio of NPK: 15-30-15
- Approximately 1.5 pounds
- encourages most flowers to bloom more
- Easily combines in a watering can
- increases some plants’ size
- Must be routinely administered and suitably diluted.
How can I encourage my hydrangea to bloom more?
Early spring or mid-July through late summer are the blooming seasons for hydrangeas. The methods for extending hydrangea blossoms’ life and producing more of them are discussed below.
Plant the hydrangea where it will receive morning light and afternoon shade, keep the soil continuously moist, and treat it in the spring with a fertilizer that is well-balanced to encourage more flowers. To encourage more blossoms, don’t prune your hydrangea too frequently. Hydrangeas bloom on the growth from the previous year.
Continue reading to find out how to lengthen the time that your hydrangea blooms as well as my personal pick for the best fertilizer for hydrangeas to enhance blossoming.
Does using coffee grounds on hydrangeas work?
Coffee has always been amazing to me. If not magical, then pretty close. I mean, I’m a writer, and I’m pretty convinced that writers account for at least half of the sales in the coffee industry. But this also means that every day, we throw away tons of used coffee grounds. Although coffee grounds alone are not very harmful to the environment—in fact, I’ll teach you how to use them in your yard in a moment—they do add to the volume of landfills. Coffee, ever the sociable drink, mixes with other trash in foul trash heaps to produce methane, which as we all know is a greenhouse gas that contributes to climate change. So the next time, try something a little different rather than simply throwing the grinds in the trash.
If you just drink one pot of coffee per day, you will have a lot of wonderful, mineral-rich grounds left over after you finish your first pot of the day, which you can use to enhance your garden. We coffee aficionados enjoy the strong coffee fragrance, but insects that harm flowers respond negatively to it. Coffee grounds not only deter ants and snails, but they also stop neighborhood cats from digging in your flowerbeds. Therefore, pile the material high around your preferred plants to ward off slimy, stingy, or fluffy pests.
Use coffee grinds to alter the color of your hydrangeas. The soil around hydrangeas becomes more acidic thanks to coffee grinds. Chemically speaking, the plant can more readily absorb naturally occurring aluminum in the soil as a result of the increased acidity. Pretty blue flower clusters are the result. Coffee grinds let you play with the color to transform pinker blossoms into other shades of blue, or perhaps a shade of purple in between, even if coffee won’t influence the brilliance of the flowers (pale blue flowers will remain pale blue, for example).
Coffee contains nitrogen, which helps plants grow, so give your plants a boost by turning the grinds into a natural fertilizer. Add a quarter cup of coffee grounds to four or five liters of water to make a “tea of coffee grounds.” Pour the liquid over all of your plants the next morning for a nutrient boost after letting it set overnight.