If you want to add a showy splash to your garden, hydrangeas are well worth your consideration. These shrubs produce a riot of spherical flowers throughout the spring and summer. While the flowers have a delicate appearance that suggests lots of care requirements, hydrangeas are quite easy to nurture into a thriving life if you have the right conditions and an understanding of their needs. Get set for something special this year by learning a little about the beautiful hydrangea.
The hydrangea is a flowering shrub that blooms in spring and summer. While the plants are large and, when healthy, very striking, hydrangeas require minimal maintenance in the hands of a well-prepared gardener — even an inexperienced one. Hydrangeas can grow as high as 15 feet and fill out rapidly. A hydrangea shrub can reach its full size in just one growing season. Hydrangeas grow as perennials in any hardiness zone between three and seven. Flowers begin to appear in spring, and they can often last through summer — sometimes even beyond. With a little planning, hydrangeas could serve quite well as one of your garden’s key flowering plants.
A hydrangea is just like any other impressive plant you want to introduce to your garden: It has to be planted correctly if it’s going to thrive. You need to choose the right location, make the soil welcoming, and plant at the right time. Skillful planting is a large part of raising healthy, impressive hydrangeas.
The Right Time to Plant Hydrangeas
The most effective time to plant hydrangeas is in the fall. Failing that, they should be placed as early as possible in the spring. A hydrangea shrub needs as much time as possible to build up its root system before it starts to bloom. Plant hydrangeas in the early morning or late afternoon so that they will have fewer problems with heat stress. Your new plants will need frequent watering until they get established.
The Right Place for Hydrangeas
Picking a suitable location is important if you want to raise strong hydrangeas. Beds immediately adjacent to a shade structure (like a wall or fence) are very popular. Hydrangeas prefer the relatively cool light of the morning sun and need shade from the highest temperatures in the afternoon. Thus, you should look for a location that’s sunny in the morning and shady in the afternoon. Hydrangeas often do well on the north or south side of a house. Do not plant hydrangeas under trees; this can cause the two plants to compete with each other for water and soil nutrients. A location that offers hydrangeas some protection from wind is good, too.
The Right Soil for Hydrangeas
Hydrangea shrubs thrive in soil with high organic content. They also need good drainage. Hydrangeas are relatively thirsty plants, but they will not do well in soil that tends to get waterlogged. In constantly soggy conditions, the plants may succumb to root rot. This can lead to plant death in a matter of weeks. If your soil is very dense, improve its condition by adding lots of compost before planting your hydrangeas.
The Right Way to Plant Hydrangeas
Prepare a good planting hole for a hydrangea by digging roughly two feet wider than its root ball. Adjust the depth so that the top of the root ball is level with or even slightly above the surrounding ground. A high planting gives your hydrangea better drainage.
Propagation – Or, The Right Way to Multiply Hydrangeas
Hydrangeas are easily encouraged to reproduce through basic propagation techniques. The bigleaf and panicle species are particularly suited to layering propagation. The best time for this is in the early or middle part of summer.
Here’s How To Do It:
- a) Dig a small trench leading away from the hydrangea.
- b) Bend a branch into the trench, arranging it so that six to 12 inches of branch extend past the contact with the soil
- c) Scratch up the branch’s bark where it touches the soil in the trench.
- d) Fill the trench and place a sturdy weight (brick, paver, stone, etc.) on top.
- e) The branch will produce a new root system. After this is done, you can dig it up and replant it elsewhere.
Smooth and oak-leaf hydrangeas are even easier to propagate. They will put out new shoots all by themselves. Simply dig up a young shoot and carefully separate the roots. The new plant can then be moved to a new location.
Tips for Hydrangea Care
Despite the delicacy of hydrangeas’ leaves and flowers, they’re surprisingly low-maintenance plants. The following tips will teach you everything you need to know:
- Water at a rate of 1 inch every week during the growing season. Water deeply three times a week; this encourages root growth. Use a little more water for bigleaf and smooth hydrangeas as these varieties are thirstier. The best way to deliver deep watering is with a soaker hose. You should aim to keep moisture away from the flowers and leaves. Morning is the best time to water so that your hydrangeas will not wilt on hotter days.
- Apply mulch around your hydrangeas to hold moisture in the soil and keep its temperature down. Organic mulches are great, as they break down over time to add more nutrients to the soil.
Fertilize According To The Needs Of Your Specific Variety Of Hydrangeas:
- a) Bigleaf hydrangeas need three light fertilizer applications. Try March, May, and June.
- b) Oakleaf and panicle hydrangeas need two applications. Try April and June.
- c) Smooth hydrangeas need one fertilizer application in late winter.
The best way to defend hydrangeas against pests and diseases is to pick cultivars with bred-in resistance. Hydrangeas can suffer from blight, wilt, leaf spots, and mildew. Pests are generally not a problem, though stressed-out plants may become vulnerable to harmful insects like aphids and spider mites. Judicious care is the best way to defend hydrangeas against pests and diseases.
There are four main varieties of hydrangea suitable for growing in the United States:
- Oakleaf hydrangeas are the most heat-tolerant variety. These are ideal if you live in an area that is zone 5 or warmer.
- Bigleaf hydrangeas are the most common variety, thriving anywhere between zones 5 and 9.
- Panicle hydrangeas are best suited to zone 3. They also grow large, often reaching as high as 15 feet.
- Smooth hydrangeas are the most cold-tolerant variety. Because their flower clusters come in white, these are often called “snowballs.”
Additional sub-varieties that might be particularly appealing:
- French: This is a bigleaf hydrangea that produces notably vibrant flower clusters. Thus, it is also called “the florist’s hydrangea.”
- Mophead: This is a bigleaf hydrangea noted for its large and very circular blooms.
- Lacecap: On this hydrangea’s blooms, large flowers cluster around smaller buds that appear not to open fully, producing a pleasingly delicate look.
- Endless Summer: This is a unique bigleaf cultivar first discovered in the 1980s. What sets it apart is an ability to survive cold zone 4 winters.
- Peegee: The panicle Grandiflora (PG) cultivar grows big enough to nurture into the form of a tree with careful training.
- Blue: These are bigleaf hydrangeas that produce blue flowers. The coloration is dictated by soil content, and a blue hydrangea’s blooms may come in different colors after its first year.
- Pink: There is a range of pink hydrangea cultivars, covering a spectrum from the faintest blush to the hottest pinks.
Frequently Asked Hydrangea Questions
When Do Hydrangeas Bloom?
The main blooming season for hydrangeas stretches from spring to early fall, but your specific cultivar and planting zone also play a role. Buds begin to appear on new hydrangeas in early summer; these will start to bloom the following year. Note that in very hot climates, hydrangeas may stop blooming in the hottest part of the year. If tended properly, these plants will re-bloom in the fall.
Do Hydrangeas Need to Be Cut Back?
Unless hydrangeas are planted too close to each other or other plants, there’s no need to prune them. Simply check for deadwood periodically and remove any you find.
Can You/Should You Deadhead Hydrangeas?
By deadheading hydrangeas, you can extend the blooming season into the fall. Hydrangeas can be cut well before the flower wilts. Avoid deadheading hydrangeas after the beginning of the fall. Removing flowers at that point might encourage unwanted new growth too close to winter.
Can You Control Hydrangea Color?
Some (not all) hydrangea varieties offer you a unique opportunity to change the color of the plant’s blooms. Bigleaf varieties (H. macrophylla) will bloom blue if the pH of the soil around them is low. This is because they can absorb aluminum, the element responsible for the beautiful pigmentation. If you want to turn your hydrangeas blue, use sulfur or peat moss to bring the soil pH down. Adding aluminum sulfate to the soil throughout the growing season is also a good idea. The process can be reversed to encourage pink and red blossoms. To do this, add ground limestone to bring your soil pH up.
If you want to add increased precision, you can use a soil pH test to adjust your hydrangea color. Keep the pH below 7.5; higher levels can lead to plant damage.
Hydrangea colors fade naturally in the fall. Do not let this behavior worry you; the plants will come back as colorful as ever next year.
Can You Grow Hydrangeas in The Shade?
Hydrangeas do well in occasional shade, but in heavy shade, they may fail to bloom.
Can Hydrangeas Grow in Full Sun?
Hydrangeas fare poorly if they’re exposed to round-the-clock sun, particularly in the hotter part of the afternoon.
Your latitude affects how much sun your hydrangeas require. In more northerly gardens, hydrangeas will appreciate six hours of sun a day. Further south, though, hydrangeas may require only three hours to thrive.
Can You Grow Potted Hydrangeas?
Hydrangeas can be adjusted to live in a pot with little difficulty. This allows you to enjoy the impressive sights of the flowers even if you’re running out of soil space. You will need a pot big enough to comfortably accommodate a mature plant of your cultivar. An 18-inch diameter pot is an absolute minimum. Hydrangeas do best in non-porous pots that will maintain a more consistent moisture level. For pot-growing, dwarf hydrangea cultivars are ideal. Some good examples are Buttons ‘n Bows, Little Lime, and Mini Penny.
How Can You Stop Hydrangea Wilting?
The best defense against wilting is regular morning watering. Sometimes moderate afternoon wilting is inevitable; this is common when you have a mismatch between your cultivar and your climate. Laying down a thicker layer of mulch can help reduce the soil temperature and discourage wilting.
Resist the temptation to make adjustments if your hydrangeas bounce back quickly as soon as temperatures drop in the afternoon. Brief mid-day wilting is not a plant-threatening problem. Starting to overwater, though, can be — you risk drowning your hydrangeas!