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Many know hydrangeas for their dreamy blue summertime blooms, but hydrangeas are so much more. In gem tones of blue, purple, red, as well as pastel pinks, and rich creams on a backdrop of deep green leaves, hydrangeas are a fit for any garden. Growing hydrangeas can be one of the more rewarding plants to grow in your garden due to their stunning looks, and hardy nature.
The blooms on hydrangeas are irresistible, making it a one-of-a-kind landscape plant. Either clustered together or climbing up a trellis, hydrangeas are easy to grow and a great way for novice gardeners to make a large impact in their garden.
These shrubs stand out on their own but also pair well with low-growing perennials such as Heuchera, Nepeta, Hosta, Salvia, or any other combination you can dream up.No matter where you plant your hydrangeas, you will enjoy their stunning blooms.
Hydrangea Plant Overview
| Plant Type Shrub, Vine Season Summer to Early Fall Pests Aphids, Beetles, Spider Mites Family Hydrangeaceae Genus Hydrangea Species Hydrangea spp Exposure Partial Sun | Diseases Fungal Maturity Date 3-4 years Maintenance Medium Growth Rate Rapid Soil Type Well-draining, Acidic Native Area Asia Plant Spacing Variety Dependent | Attracts Pollinators, Common Wildlife Hardiness Zone USDA 3-7 Plant With Low Growing Perennials, Annuals Don’t Plant With Lavender, Deep Shade Plants Planting Depth Depth of Root Ball Watering Requirements Moderate Height Variety Dependent |
Plant History
Hydrangeas were first cultivated in Japan. They can still be found growing wild in the mountainsides of Japan today. It is said that they made their way to Europe via North America in 1736. It is unknown how the hydrangea made it from Asia to North America, however, there have been fossils found in North America dating back 40-65 million years ago.
Once the hydrangea gained European praise, it was given the name Hydrangea for the shape of its flower. Botanist Grovonius chose this name because the shape of the flower reminded him of an ancient water pitcher; “Hydra” for flower, and “Angeion” which means pitcher.
While it is not a popular herbal remedy, hydrangea root has been used to treat issues associated with the bladder for hundreds of years.
Over the years, hydrangea stems have become popular in floral bouquets; I even used some at my wedding in my centerpieces. The blossoms signify gratitude, unity, and togetherness.
Cultivation
Hydrangea is quite literally in a family of its own, Hydrangeaceae. These plants are very versatile. They can be used as a landscape planting in clusters or as a point of interest, along walkways providing a nice border, peeking through fences where you may not have enough sun for roses, in large containers, as a foundation planting, they can even be found in tree form…the list goes on and on.
Hydrangea has more than 70 species. In North America and Europe, there are six species that are most popular, and while they are all similar they also have great differences.
- Hydrangea arborescens, or smooth hydrangea
- Hydrangea macrophylla, or bigleaf hydrangea
- Hydrangea paniculata, or panicle hydrangea
- Hydrangea quercifolia, or oakleaf hydrangea
- Hydrangea serrata, or mountain hydrangea
- Hydrangea anomala ssp. Petiolaris, or climbing hydrangea
Propagation
There are two common ways to propagate hydrangeas: cuttings and layering. Both are relatively simple and have similar success rates. Let’s take a look at how to propagate from either way you decide to start.
Propagation From Cuttings
The first step to this propagation process is to find a green branch or stem that has not yet flowered in the current season, and snip! This cutting should be about five to six inches in length with a few sets of leaves on it. Next, remove the bottom two sets of leaves. This will expose two leaf nodes which will become the growth point for your new plant!
Fill a container with a propagating mix. Any sterile type of medium will work; coarse sand or vermiculite would both be great choices! Use whatever size pot you have on hand. If you happen to have a ½ gallon pot on hand I would use that, as it would prevent you from having to transplant the cutting too quickly or too often.
Dip the bottom of your cutting into some rooting hormone powder, this is available at most garden centers. It is optional to use a rooting hormone, but it will increase the chance of successful rooting and protect the cutting from any unwanted diseases. Gently press the cutting into the soil, water the cutting well, and then allow the water to drain out of the pot.
Once the pot is well-drained, cover the cuttings and the pot with plastic without allowing the plastic to touch the plant material. You may need to use planting stakes or even chopsticks to achieve this. Covering the cutting with plastic will create a greenhouse-type atmosphere. Keep the cuttings in bright light, but not direct sun as the plastic could cook the fresh cuttings. Do not water again until the top of the soil begins to feel slightly dry.
It will take about two to three weeks for the hydrangea cuttings to root. You can lightly pull on the cutting to see if the roots have taken hold. At this point, you can continue to transplant the cuttings into larger pots until you are ready to plant them in the ground, or you can plant right into the ground.
Propagation by Layering
Ground layering is another easy and fun way to propagate hydrangeas. This process can be done right in your garden. The few simple steps will encourage roots to form off of an existing shoot.
Begin by selecting a branch that is close to the ground. Remove the leaves from about five inches of the branch where it will make contact with the ground. Next, scratch a little of the bark off of the underside of the branch in this same area. Make sure at least one leaf node will be under the ground, but the more the merrier!
Dig a small hole about two inches deep and lower the branch into it. Cover generously with garden soil and use a stone or brick from your garden to help keep everything in place. Water occasionally.
When the roots of the new plant form you can cut it from the mother plant and move it to its new home in your garden. Allowing this new cutting to stay in place for a week or two before transplanting will give it time to adjust to living on its own.
Planting
I love to buy my hydrangeas from plant sales at local botanical gardens, these are typically grown from cuttings. Most nurseries and garden centers have many different varieties available in all sorts of sizes. The same planting process will work for mature cuttings as well.
Once you have selected the perfect plant from your favorite garden center, be sure to keep the mature size of the hydrangea in mind when you are picking where you want to plant. Making sure you have enough room for the plant at its mature size will reduce the amount of pruning you might need to do. Before you dig your hole, water the plant while it is still in its container. This will help to prevent any transplant shock.
Dig a hole twice as wide as the size of the pot. If your soil is dense or clay, be sure to amend it with compost or peat to help the water drain which will help prevent root rot. Do not plant deeply, keep the base of the plant at the same depth as it is in your nursery pot. Water it in well immediately after planting. Plant in late spring or fall. Once your hydrangea is planted be sure to keep it watered until it is established.
How to Grow
When growing hydrangeas, there are many things to take into consideration. You want to ensure that you have enough light, water, and the right climate. If you are planting with other plants, consider hydrangea companions that won’t competing for nutrients when planting.
You also want to make sure your soil conditions are favorable, and use the recommended fertilizer when it’s time to feed your plant. Let’s take a look at each factor you’ll need to prepare for when growing hydrangeas.
Light
All hydrangeas will do well planted in partial sun, specifically morning sun and afternoon shade, which is especially true for the macrophylla. If you have more sun you may opt for Hydrangea paniculata which can tolerate sun all day as long as there is adequate moisture.
Water
Once you have your hydrangea established in the ideal location in the garden your watering will be moderate. I prefer to water my hydrangeas in the morning before the stress of the summer heat has a chance to get to them.
If your hydrangea is needing water it will be easy to tell, the flowers will begin to wilt and the leaves will droop down towards the ground. The good news here is that a good soaking should relieve these symptoms.
When watering your hydrangea by hand, aim for the base of the plant and the soil surrounding it. Hydrangeas are very susceptible to fungal diseases, and water that is left sitting on the leaves will make these diseases more likely to appear on your plant, so try to avoid overhead watering.
If you use an irrigation system, drip irrigation is the best option for your hydrangeas as it will keep the flowers and leaves dry, but well watered.
Keep an eye on the weather- if it’s going to be especially hot you may need to water a bit more frequently. Again, use the leaves as your helper… if they are starting to droop get out there and water!
Soil
One thing hydrangeas do NOT like is having wet feet. The best way to prevent this, while also making sure your plant is getting enough water is to make sure that the soil you have is well-draining. Adding organic material such as compost, peat, or even dried leaves can help with this.Hydrangeas like acidic soil, so keep that in mind when making your soil selection.
Climate and Temperature
Hydrangeas are hardy in USDA zones 3-7 as perennials. Most varieties will be just fine as long as you are in these zones. That being said, many hydrangeas have also had success in warmer climates. In these warmer zones, the plant may not have the opportunity to go dormant. They will also prefer more shade and might require more frequent watering.
Fertilizing
Similar to the watering needs of the hydrangea, they don’t need anything too extensive once they are established. The best way to fertilize your hydrangea is to use manure or compost around the base of the plant. Not only does this produce excellent results, but it will improve the conditions of your soil over time.
If you do choose to go the chemical route, look for a fertilizer labeled for shrubs and trees. Many of these fertilizers are available on the market in slow-release formulas.
Be sure that the slow-release granules are covered with soil to ensure they release properly. You can do this by simply raking over the surface area around the plant before applying.
Another chemical option is a simple 10-10-10 fertilizer. Do not fertilize hydrangeas after August as the plants are already preparing to go dormant.
Maintenance
If I have a very prolific blooming shrub I will cut flowers for arrangements. I try to make this a two-for-one task, when I make the cut, I try to cut it to where I would like it to be pruned for the next season.
Once a frost hits, the leaves will begin to turn yellow and fall to the ground. Remove these leaves by hand, or by using a small rake. Be sure to grab the leaves out of the crown of the plant.
This can get a little scratchy, so grab some long gardening gloves and just reach into the base of the plant to clear everything out. This will help clear any leaf litter that could be diseased. It will give your plant lots of air circulation which will help keep those pesky fungi away.
Depending on where you live it may be important to protect your hydrangea over the winter. This is important in areas where temperatures drop below five degrees on most winter days. I have never protected my hydrangeas, and have had minimal issues- maybe an occasional wind burnt bud here and there.
If you do choose to protect your plants, use some stakes and chicken wire- be sure to leave enough room so that the wire doesn’t rub against your plant. Insulate your plant using something that does not compact too easily such as pine straw, or even dried leaves from your oak tree. If your hydrangea plant is small enough you could even use an upside-down tomato cage to achieve this.
Pruning
When you are pruning your hydrangeas it is important to keep in mind which species of hydrangea you are working with. The reason for this is because some species bloom on what is called “old wood,” which is any growth from the previous season. These species are macrophylla, serrata, quercifolia, and anomala.
The old wood species don’t typically require a lot of pruning. They are at their best when they are left to grow freely, and pruned only for containment and to remove winter kill. Quercifolia can be left until April before they are pruned.
For anomala it’s best to prune after flowering in late June by simply removing the spent blooms. Macrophylla and serrata both have big heads of flowers, one mophead, one lace. They respond to the same type of pruning.
Other species bloom on “new wood,” which is the growth from the current season. These species are arborescens and paniculata.If you are working with a new wood bloomer you really can’t go wrong, it is best to prune in the late fall.
Hydrangea Varieties
There are many different hydrangea varieties. Many of them perform well in full sun, but some will even grow well in partial shade for full shade. Let’s take a look at some of the most popular varieties you’ll likely grow.
Hydrangea macrophylla ‘Nikko Blue’
Nothing can quite beat Hydrangea macrophylla ‘Nikko Blue’. These classic, beautiful mop head hydrangeas have long-lasting blooms. These blue blooms are a New England classic and are an easy way to give your garden a cottage vibe.They are also one of the most popular blue hydrangeas you are likely to find in east coast garden spaces.
Hydrangea macrophylla ‘Lady in Red’
In a sea of blue and purple blooms Hydrangea macrophylla ‘Lady in Red’ is a show stopper in your garden. Although it is the same species as the mophead hydrangea, Lady in Red is a lace cap variety that offers a great contrast to your garden.
This lace cap hydrangea begins its season in the early summer with a light pink flower and slowly matures to a deeper pink and occasionally a blue. Before the blooms appear this plant has red stems and red veins in its green leaves.
Hydrangea paniculata ‘Limelight’
Hydrangea paniculata ‘Limelight’ grows from 6-8 feet tall, making this variety a great choice for privacy planting. The cone shape blooms vary from cream to light green, to pink, sometimes all on the same bloom.
Whereas most of the hydrangea varieties prefer partial sun, paniculatawill tolerate some more sun. Plant these giant beauties with other sun-loving perennials such as Nepeta for a beautiful border along a fence or deck. If you love the colors on this plant, but not the height, opt for yet another variety, Hydrangea paniculata ‘Jane’ also known as Little Lime, which maxes out at five feet.
Hydrangea anomala ssp. petiolaris
Proving that your garden could truly be full of hydrangea, Hydrangea anomala ssp. petiolaris, or the climbing hydrangea is another stunning, versatile option. This perennial climber can be found growing up the trunks of trees or used on arbors, and I currently have them climbing up trellises that cover my downspouts.
Large lace-cap white flowers decorate these flowering vines and bloom earlier than its relatives; in early-mid June. These blossoms are not big and showy like its cousins, they remind me of baby’s breath and offer a really pretty accent to your garden. Is a great option for a vine when full sun isn’t an option.
Pests
Many of the pests that are found on hydrangea are common garden pests. The number one thing pests will go for on a hydrangea are the juicy green leaves. If you have planted a wildlife salad bar nearby you may even find some common wildlife dining on the leaves. It can be disappointing to see your beautiful leaves getting eaten, but do not worry. These pests are easily controlled.
Aphids
The bullies of the garden have been known to appear on most plants, including hydrangeas. Their feeding can cause some yellowing of the leaves and stems. Aphids also produce waste that is high in a sugar called honeydew. This honeydew will attract ants. The ants will not harm the plant, however, they will protect the aphids from predators.
To control an infestation of aphids you could try brushing them off with your hand, hosing them off with a strong spray, adding natural predators, or using insecticidal soap.
Japanese Beetle
Another very common summertime pest is the Japanese beetle. Japanese beetles can be a problem on many plants, they are not picky. They tend to be a problem on oakleaf hydrangeas, but not typically on the other species of hydrangea.
These beetles are known for leaving a lacy look to a leaf by eating the foliage and leaving the veins behind. Do not use pesticides while the hydrangeas are blooming to protect pollinators. Using pesticides can lead to discolored flowers, or fewer hydrangea blooms. Instead knock the beetles off of the leaves into a bucket of soapy water to kill the beetle.
Spider Mites
Spider mites are a common insect that can be quite destructive if left untreated. Their favorite hosts are plants that have been stressed by heat and drought. Spider mites will feed on the leaves of a plant leaving a freckled appearance.
Another sign that you may have a spider mite infestation is webbing. Spider mites love the hot, dry weather, so the best way to control the mites is by keeping your plants watered properly.
Typically mites can be controlled by predators, or by spraying the plant off with water. If you are keeping your hydrangeas watered and you still find them being attacked, take solace in knowing that the healthier your plant is the more likely it will be to recover from mite damage.
Diseases
Hydrangea shrubs and vines can struggle with fungal diseases. The good news here is most of these are harmless and will just take away from the beauty of a plant.They are also some of the most common hydrangea problems that many new and experienced gardeners will face.
Leaf Spot
Hydrangeas are susceptible to leaf spot which can be caused by a number of different fungi. Leaf spot could present itself as light brown spots with a darker brown border. This can be prevented by minimizing moisture on the leaves.
Powdery Mildew
Powdery mildew can occur on all hydrangeas but is most common on bigleaf hydrangea. You will see a white fungus that resembles powder on the surface of the leaf. In some instances, you could see yellow or purple leaf blotches. Powdery mildew typically does not hurt the plant but can be aesthetically unpleasant. Clean up fallen leaves and dead plant tissue to help prevent new infections.
Botrytis Blight
Botrytis blight is a common disease that attacks hydrangea. You will notice small wet spots on the leaves that will quickly expand into brown irregularly shaped blotches. Unlike the other mentioned diseases, this can also affect the flower buds.
Botrytis blight thrives in humid and wet conditions. This fungus will survive on fallen plant leaves, meaning moisture from the air or from irrigation can splash spores up onto your healthy plant and spread. The best way to prevent this fungus is by clearing plant debris from around the plant, and if needed a horticultural oil can help as well.
Root Rot
If you are paying close attention to your gardens it will be hard to miss the signs of root rot. You will notice root rot by one or more shoots drooping and not responding to heavy watering. These plants will eventually die.
Plants that are drought-stressed are most susceptible to catching root rot. The fungus will produce white mats under the bark or near the soil line. After heavy rain, you may also notice mushrooms growing above the damaged roots. Good growing conditions are the best way to keep your hydrangea protected from root rot.
Plant Uses
The shrub-like nature of Hydrangeas makes it an excellent foundation plant. The larger varieties can be used as a hedge that will offer privacy in the summer months. The vine varieties can be used on a trellis, climbing up the trunks of trees, or the face of a building. Hydrangeas can also be used in containers to make a splash.
The blooms are excellent additions to your flower arrangements, and when allowed to dry out naturally they will last for years. My favorite way to dry hydrangea flowers is very simple. Fill a vase with flowers, fill the vase with water. Do not change the water. Allow the stems to suck up the water until it is all gone. The flowers will dry and remain intact.
Frequently Asked Questions
When is the best time to plant hydrangea?
The best time to plant hydrangea is in the late spring or the early fall. These are the periods of the growing season where the plant is still dormant, making the risk for transplant shock lower. Whenever you decide to plant your hydrangea, be sure to water thoroughly until the plant has established itself.
How do you cut back hydrangea?
Hydrangea plants with enough space in the garden do not need to be pruned. Occasionally removal of deadwood may be needed and is best done in the fall.
If you have a new wood bloomer (arborescens or paniculata) and you wish to cut your plant back you can cut them back to within a few inches of the ground.If you don’t have a new wood bloomer, be careful. You will not kill the plant if you cut it back, but it will take a year or two for the plant to bloom again.
Can you control hydrangea color?
Yes! Hydrangea macrophylla, or bigleaf hydrangea, and to a certain extent H. serrata, will react to the pH of your soil as well as the level of aluminum in your soil by changing color. Soils that are more acidic, below 5.5 pH, will favor blue flowers by allowing the hydrangea to absorb more aluminum. Whereas soils that are above 6.5 pH, or “sweet” soils, will produce pink flowers on your hydrangea. Before amending your soil with anything a soil test is recommended.
Aluminum sulphate is readily available, and the best product to use to enhance the blues of your flowers. Use a “less is more” approach when applying this to your plants. A drench of one tablespoon of aluminum to one gallon of water is the safest application rate. If the plant is dry, water before applying this solution. This method should only be used twice a year; once in April and once in May.
If you are wishing to enhance your pinks or reds, using garden lime will be your best tool. Apply a powder form of lime to the base of the plant in April and again in October. Lime works by raising the pH of the soil which will eventually inhibit the ability of your plant to utilize the aluminum and in turn enhance the pinks and reds of your plant.
Why aren’t my hydrangeas blooming?
This can be so frustrating! You think you’re doing everything right, you have been anxiously awaiting this season’s blooms, and the next thing you know- no flowers! This is where following pruning instructions is so important. I would say the number one reason you aren’t getting any flowers is that you pruned at the wrong time for your species. Once you have discovered if your hydrangea blooms on old or new wood you can assess your pruning habits.
If it appears that you have been pruning correctly, I would suggest a soil test. A high level of nitrogen will help your hydrangea produce lush green leaves, but with a very small amount of flowers. Plants, shrubs included, need phosphorus to produce flowers. Fertilizing with a 10-10-10 solution is a great start. If you find that you are needing more phosphorus, adding bone meal is a quick and easy option that is available at most garden centers.
Why are my hydrangea flowers small?
Check the amount of light your hydrangea is getting. While they do require shade in order not to scorch, they do need sun to be able to produce prolific blossoms. Excess shade will cause the leaves to become deeper green, and larger in size.
To correct this you may need to prune whatever plant may be causing the extra shade, or just transplant the hydrangea to a sunnier location in your garden. If you do choose to transplant your hydrangea it is best to wait until late fall or early spring. I prefer to transplant in the spring because it is easier to remember to get out and water the new transplants than it is in the fall when the watering portion of the season has slowed.
Can I use hydrangea in container gardens?
Yes! The care for the plant is essentially the same in containers as it is in the garden. It is important that the container is large enough to allow the hydrangea room to grow. Try to stick to a light-colored pot, where a dark-colored pot could absorb too much heat and cause the plant to stress. Consider using a dwarf hydrangea variety for your pots if your space is limited. Pair with sweet potato vine or other trailing annuals.
Final Thoughts
If you are just getting started on your gardening adventure, or are just simply new to hydrangeas this is an absolute must-try plant. They truly are one of the most breathtaking plants out there.
There was a time in my life when I thought hydrangeas were an overused plant in the North Eastern United States. It almost seemed like a requirement to have a cluster somewhere on your property. However, time has passed and my mind has not changed but my perspective has. They are overused for a reason. The variety and availability of these plants is extensive, making it easy to find a plant that will suit the needs of your garden. They are simple to maintain, and the result of your minimal care is just incomparable.
