Both hydrangeas and rhododendrons are sensitive to the pH of the soil, and both thrive on acidic soils with a pH of between 5 and 5.5. However, hydrangeas are less sensitive and can grow in higher pH soils.
Depending on the pH of the soil the shrub is growing in, French hydrangea will produce different types of flowers. The flowers are blue in acidic soils and change pink in alkaline soils. The blossoms are white or light green in neutral soils. Rhododendron blooms’ colors are unaffected by the pH of the soil.
Are hydrangeas and rhododendrons the same thing?
The numerous rhododendron and hydrangea species provide a wide range of sizes and hues. Both species are frequently utilized in upright shrub borders and bulk plantings. From the Catawba, which may reach heights of 6 to 20 feet and widths of 5 to 8 feet, to the plumleaf, which can reach heights of 8 to 12 feet and widths of 6 to 8 feet. Rhododendrons can be seen with flowers that range in color from bright orange red, deep crimson, purple, yellow, cream, or gold-orange among their enormous green leaves, depending on the cultivar and season. The panicle, which may grow up to 20 feet tall, is the largest kind of hydrangea, measuring 2 to 6 feet tall and 4 to 6 feet broad. Blue or pink blooms are arranged in ball-shaped clusters on hydrangea flowers. They begin as a light green color that becomes to white, then fades to rose or purple pink by summertime before turning tan. Although other kinds of hydrangea have rounder leaves, oakleaf hydrangea is named for its green, serrated leaves that resemble oaks.
Azaleas
Partial of the greatest plants to grow next to hydrangeas include azaleas and rhododendrons because they share similar preferences for some shade and high-quality organic mulch.
These plants also prefer somewhat acidic soil, just like blue hydrangeas do. Avoid the pink ones or let them turn blue because they prefer more alkaline soil and won’t thrive with acid-loving azaleas.
Azaleas are wonderful companions for any acid-loving plants because they are not troubled by insects or illnesses. Try the white or yellow-flowering varieties to contrast with blue hydrangeas for a magnificent spectacle. White hydrangeas look good with any shade of pink or salmon.
The majority of azaleas bloom throughout the spring and into the summer, but other kinds bloom at other times of the year to keep the garden interesting.
Heuchera
This perennial plant is renowned for its eye-catching leaf, which comes in hues of rose, gold, lime green, purple, and red.
These North American natives, sometimes known as Coral Bells, thrive in shady woodland settings and are wonderful companion plants for hydrangeas.
In the spring and summer, they produce tiny bell-shaped flowers that are rich in nectar and draw a large number of pollinators, such as butterflies and birds.
When hydrangeas are in bloom, plant as a border in front of them and pick combinations that are aesthetically pleasing. White hydrangeas and lime green Coral Bells are one of the traditional combinations, but this adaptable plant has a wide range of uses.
Sweet Potato Vine
They produce masses of incredible colorful leaves that range in hue from gold, bronze, brown, and almost black to bright green, even though they prefer full sun. As a groundcover or border plant in front of hydrangeas, the compact size is ideal.
While there are hydrangea types for USDA zones 5 through 11, sweet potato vine grows best in zones 8 through 11, so that should be considered before planting.
Hostas
Another plant that complements hydrangeas admirably is the hosta, which prefers similar environmental factors.
Although some types may even grow in deep shadow, they thrive in partial shade. They also prefer nutrient-rich, somewhat acidic soil. Summertime brings forth the most in these plants, which brilliantly accentuate the hydrangea blossoms.
There are numerous sizes (ranging from one to three feet tall) and colors available, including green, lime green, blue green, and white variegated variations. Plant with hydrangeas as a border for a bounty of large leaves.
What kind of plant is the rhododendron?
The genus Rhododendron is the home of all rhododendron plants. The first component of a live thing’s scientific name is its genus. The Rhododendron genus contains a wide range of plants. Because the many kinds can easily hybridize, classification can be challenging. New hybrids with intriguing flower traits are routinely produced by plant breeders. The names of cultivated plants are typically lovely and descriptive. Three of my favorites are Pink Pearl, Saffron Queen, and Paprika Spiced. They make me think of beautiful pictures.
In my location, grown rhododendrons have huge, evergreen leaves and stunning, late-spring flowers that unfold. The majority of my images of ornamental rhododendrons feature their enormous, oval leaves, which have dull, pale green undersides and glossy, dark or medium green upper surfaces. The bell-shaped blooms are born in trusses, which are collections of flowers. They may be any color—white, yellow, orange, pink, red, or purple. Frequently, the blossoms will have spots that are a different color than the rest of the flower.
Although some of my local plants bloom in April, the majority of them bloom in May. June and occasionally even later in the summer still have flowers. However, they have already begun to fall to the ground by early June. Some cultivated rhododendron varieties bloom earlier or later in the year than the ones that are well-liked where I live.
Rhododendrons come in about a thousand different species. They are a member of the Ericaceae family, also known as the heather family.
Are rhododendrons and azaleas the same thing?
Rhododendrons and azaleas are well-liked garden shrubs for gardens of all sizes because they produce a stunning display of vivid flowers throughout spring and summer. But how do the two differ from one another?
Azaleas and rhododendrons are both members of the rhododendron family. Azaleas are a sub-group of the genus Rhododendron, which is a genus (group) of plants with shared traits, rather than a separate genus. While there isn’t a clear cut way to tell azaleas from rhododendrons apart, each has unique qualities and traits that are crucial to know when selecting the perfect plant for your garden.
- Deciduous versus Evergreen. Evergreen rhododendrons retain their leaves all year long (technically there are 2 exceptions but we would not recommend these varieties so we ignore them here). Except for Japanese azaleas, which are evergreen, azaleas are deciduous and shed their leaves every fall. Japanese Azaleas are well-liked throughout the Christmas season due to their low growth rate and eye-catching blossom colors.
- Growth Pattern. Rhododendrons often grow to be larger plants with fewer robust stems, whereas azaleas are small to medium sized shrubs with numerous smaller stems. Rhododendrons are more grandiose in every way than azaleas, with larger flowers and leaves. The exception is dwarf alpine rhododendrons, which are significantly smaller and reach heights of 20 to 80 cm after 10 years, making them an excellent choice for clustering in a rock garden.
- Foliage. Large, oblong, leathery leaves with tiny dots or scaly surfaces are characteristic of rhododendrons. Azaleas feature smaller, narrower foliage that, in the fall, turns vivid shades of yellow, orange, and scarlet before falling to the ground. Azalea foliage is frequently hairy along the midrib and underside of the leaf (except for Japanese azaleas). In reality, Japanese evergreen azaleas have two sets of foliage per season—the first appearing in the spring and the second in the summer. A casual viewer might not realize that the first set was lost since it happens gradually. Around the time the blooms begin to fade in the spring, deciduous azaleas begin to sprout new, mid-green leaves.
- Flowers.
- Azalea blossoms are smaller and either tubular or funnel-shaped, whereas rhododendron blooms are huge, bell-shaped flowers in clusters. Both plants primarily bloom in the spring, but there is now a growing selection of summer flowering species available, including “encore azaleas,” which bloom in the early spring and then again in the summer. One of the significant differences in the initial taxonomy classifications was that azaleas have 5 stamens whereas rhododendrons have 10, provided you pay close attention to detail. Rhododendrons that have been crossed to create more eye-catching blossoms are known as hybrid rhododendrons. They feature huge leaves and large, trussed blooms, some of which are fragrant, just like classic rhododendrons, making them perfect for use as foundation or blooming hedge plants.
- Conditions for Growing. Rhododendrons are fairly picky, often needing acidic, moist yet free-draining soil that is rich in humus and partial or dappled shade (except from alpine species, which prefer full sun). Additionally, they do not react well to cold, dry breezes or exposed, hot places. Because they are shallow-rooted, like rhododendrons, azaleas are typically more tolerant of aspect, soil quality, and exposure. However, a moist, acidic soil is still a “must have.” Again, the exception is the Japanese azalea, which is more susceptible to harsh winters than both deciduous azaleas and rhododendrons.
Are rhododendrons sun or shade plants?
Traditional rhododendrons flourish in acidic soil and filtered sunlight. Although some of the more recent cultivars can tolerate different levels of sunlight, it’s always a good idea to read the plant tag or description before buying to be sure the requirements match your garden’s. The less heat the plants can tolerate, the warmer your area is.
The ideal soils for growing all rhododendrons are those with a pH of 4.5 to 6.0. Check the pH with a soil testing kit; if it is greater than 6.0, add aluminum sulfate to the soil as directed on the package.
When do hydrangeas bloom?
The type, cultivar, planting zone, and hydrangea blooming season all affect when they bloom. The majority of hydrangeas with new growth form buds in the early summer in preparation for blooming the next spring, summer, and early fall. Hydrangeas may stop flowering in the heat of the summer in hot locations, but they will blossom again in the fall.
How do you cut back hydrangeas?
Hydrangea plants don’t require pruning if they are allowed plenty of room to develop in the garden. Only the periodic clearance of dead wood is necessary.
Do you need to deadhead hydrangeas?
Your hydrangeas will continue to bloom into the fall if you deadhead them. Hydrangeas make wonderful cut flowers, so there’s no need to wait until the flower wilts. Leave the early fall blossoms alone so they can fade naturally. In the days leading up to your freeze date, you don’t want to promote new growth.
How do you control hydrangea color?
The distinction of hydrangeas is that you can modify their color. But keep in mind that not all hydrangea varieties can change their color. H. macrophylla, a species of bigleaf hydrangea, responds to changes in soil pH. Hydrangeas can absorb aluminum thanks to a low soil pH, which gives the blossoms a lovely blue hue. Reduce the pH of your soil by mixing in sulfur or peat moss to enhance the number of blue hydrangea flowers. Throughout the growth season, you can keep amending your soil with extra aluminum sulfate. When you add ground limestone to boost the pH, pink and red blooms shine.
You may precisely modify your hydrangea color using a soil pH test. To avoid the plant from being harmed, keep the pH level below 7.5. In the fall, all hydrangeas will naturally fade regardless of the modifications you’ve made. Don’t worry, the plant will display vibrant, new blossoms once more in the spring.
Can hydrangeas grow in shade?
Although they won’t blossom in complete shade, hydrangeas prefer dappled or infrequent shade. How much sun do hydrangeas need is more important to consider than whether they love the sun or the shade. Your hydrangeas require more sunlight the further north in your garden you are. A general guideline is six hours of sunlight each day. However, southern hydrangeas can thrive with just three hours of sunlight per day.
Can hydrangeas grow in full sun?
While hydrangeas prefer morning sun, they struggle in the hot, afternoon sun. For these gorgeous creatures, partial shade in the later hours of the day is optimal.
Can you grow hydrangeas in pots?
Even if you don’t have enough room in your garden to cultivate hydrangeas, you can still enjoy these lovely blossoms by learning how to grow hydrangea in a pot. As long as you follow the fundamentals of caring for hydrangeas, the procedure is rather straightforward. Select a pot with at least an 18-inch diameter to accommodate the mature size of the particular hydrangea you are growing. In order to maintain the constant moisture level that hydrangeas demand, look for non-porous containers. Excess water will be able to adequately drain thanks to drainage holes. Consider growing dwarf hydrangeas like Buttons ‘n Bows, Mini Penny, and Little Lime.
How do you keep hydrangeas from wilting?
Morning irrigation on a regular basis can assist stop withering. Some hydrangea cultivars simply can’t stand the heat. No matter how much water you give them, they will begin to wilt in the afternoon heat. Mulch applied in layers can help soil retain moisture and stay cool. You shouldn’t be concerned if your hydrangeas bloom again once the day cools. A little midday wilting is preferable to overwatering and drowning your hydrangeas.
Where to plant hydrangeas:
- A location with morning sun and afternoon shade is ideal. They’ll take more sun if you reside further north (possibly full sun all day).
- Think about the mature size and give it lots of room to expand.
- Pick a location with great drainage. If necessary, add compost to the soil.
- Plants won’t thrive if they are planted too close to a tree because of root competition and a lack of sunshine.
- Planting should not be done in open locations where strong winds could snap stems.
How to plant hydrangeas:
- By amending your soil with up to 15% organic matter and an all-purpose slow-release fertilizer, you may give your plant a good start (use half of what is recommended).
- Plant a little higher than you did while you were in the nursery container.
- In order to give the roots plenty of freedom to expand, the planting hole should be two to three times broader than the root ball.
- Before planting, gently untie the roots from their pots.
- Add the modified dirt back in and thoroughly water it.
- Planting in groups requires a minimum distance of 3 feet (more, if planting larger varieties).
Planting hydrangeas in pots:
- Put potting soil in a bag rather than garden dirt.
- Slow-release fertilizer should be added.
- For watering, leave 1 to 2 inches between the soil’s top and the pot’s rim.
- Make sure the pot includes space for the plant to grow and drainage holes.