Hydrangeas get a bad rap. They have a reputation for being difficult to grow, fussy and high maintenance. That was true of old fashion, traditional hydrangeas that only bloom on last year’s growth. It was common for a late spring freeze to damage buds resulting in little or no blooms, or a pruning mistake also resulting in no blooms.
But, the world of hydrangeas keeps changing…every season the hydrangea options get better and better. New varieties just keep coming. Take a stroll through a local nursery and you will be surprised at all the hydrangea options.
With the biggest determiner of how well hydrangeas perform being late cold spells, the absence of a late cold snap this year has the Oklahoma City area set-up for a great hydrangea show.
The introduction of the Endless Summer Hydrangea in 2004 from Bailey Nurseries with the help of Dr. Michael Dirr from the University of Georgia resulted in what many claim is the best-selling shrub of all time.
The Original Endless Summer Hydrangea
Little Lime Hydrangeas is a shorter option for smaller gardens.
Dirr had been trying to develop a reblooming hydrangea for years with no success. Then in 1998, Dirr was visiting Bailey’s test field where he found hydrangeas in full bloom…in September! Bailey Nurseries had been propagating and testing a plant they had found in St Paul, MN for 10 years with success. The plant was unique because it bloomed in the spring on last year’s growth, like a traditional old-fashioned hydrangea, and rebloomed on the new growth during the summer and into the fall.
Dirr immediately knew it was “a game changer” for hydrangeas and quickly coined the name ‘Endless Summer’.
Endless Summer varieties:
Endless Summer Hydrangea will continue to bloom into the fall.
The Original — big round blue or pink blooms
Blushing Bride - pure white blooms that mature to a pink blush.
Twist-n-Shout — reblooming lace-cap in pink or periwinkle blue with red stems.
Bloom Struck — purple or rose-pink flowers with red stems.
Summer Crush — a 2019 introduction with raspberry red or neon purple flowers with a compact growth.
Summer Crush Endless Summer Hydrangea
Summer Crush Endless Summer Hydrangea
Pop Star – Introduced in 2023, Pop Star is a compact, big-leaf hydrangea that only grows 18-26” high and wide. It is the quickest Endless Summer to rebloom.
The Endless Summer Hydrangea is like traditional hydrangeas in that they prefer morning sun and afternoon shade.
Want to learn more about Endless Sumer Hydrangeas? Follow this link: https://endlesssummerhydrangeas.com/
Another hydrangea “game changer” is Limelight. Limelight is a summer blooming hydrangea that grows in full sun!
A plant breeder in the Netherlands crossed two unidentified panicle hydrangeas and the outcome was a full sun, summer blooming show in the hydrangea family. Limelight Hydrangeas received a US Plant Patent in 2002.
I first noticed them a few years ago growing around a parking lot in downtown Oklahoma City in the middle of summer with vibrant white blooms planted in full sun. Of course, I circled the block, took lots of pictures, and started my search to find the name of the plant.
Limelight has become one of my favorite plants.
Limelight varieties:
Limelight (Original) – Blooms in mid to late summer on new growth. Flowers start green, turn to white and then back to green. Limelight is typically large 6-8’ tall multi-trunked shrubs or can be trained into a single-trunked tree formed large shrub.
Limelight Prime – All the characteristics of the original but a little smaller, 4-6’, and sturdier stems. Also, the flower color is more vivid than the original.
Little Lime – Great for smaller gardens and small pockets in the garden. Grows to 3-5’ tall.
Want to learn more about Limelight Hydrangea varieties? Follow this link to a Monrovia article: https://www.monrovia.com/be-inspired/best-panicle-hydrangea-varieties.html
Limelight Hydrangeas make a big statement grown as a single-trunked small tree.
Bobo Hydrangeas are another dwarf variety of Limelight Hydrangeas. They grow in full sun to partial shade and produce large white blooms that turn pink. A characteristic of Bobo Hydrangeas is the strength of their stems. Unlike some panicle hydrangeas the blooms don’t weigh down the stems and flop over.
Limelight Hydrangea blooms gradually go from white to lime as they mature.
Limelight – Blooms in mid to late summer on new growth. Flowers start green, turn to white and then back to green. My favorite thing about Limelight is that it grows in full sun. A hydrangea game-changer: Summer blooming hydrangea in full sun! Limelights are typically large 6-8’ tall multi-trunked shrubs or can be trained into a single-trunked tree formed large shrub. For smaller areas, try the Little Lime or BoBo Hydrangeas which grow to 3’.
Think you have to have a shady landscape to enjoy hydrangeas? Not the case with the Limelight Hydrangea. It grows in full sun with large lime to white blooms in mid-summer.
A late spring to early summer blooming hydrangea is the Oakleaf Hydrangea. The Oakleaf is one of only two hydrangea species native to the US in the SE from North Carolina, south to Florida and west to Louisiana.
Oakleaf Hydrangeas are named for the deeply lobed oak-like foliage. They grow 4-8’ tall and wide with a rounded habit. The white cone shaped flower clusters fade to pink in the summer and leaves turn deep red hues in the fall.
The Oakleaf prefers morning sun and evening shade. Too much shade and they become leggy, have fewer blooms and poor fall color.
Oakleaf – Instead of traditional mophead blooms, oakleaf hydrangeas have white clusters of cone shaped flowers. It is named for the large oak-like leaves that turn reddish-purple in the fall. It is a large shrub that blooms in the summer on new growth. It also requires less water than a traditional hydrangea.
Oakleaf Hydrangea
Oakleaf Hydrangeas is a large shrub that can reach 5-6’ with long, cone-shaped white flowers with large oak-like leavers that turn bright red in the fall.
Oakleaf Hydrangea in the Dallas Arboretum.
Oakleaf Hydrangea leaves in the fall turn vivid shades of red and purple.
Oakleaf Hydrangea with Endless Summer in the background.
Other favorite hydrangea varieties:
Annabelle – A smooth hydrangea with white blooms on the new growth. Because it is fast growing, it is common for this hydrangea to be cut all the way to the ground each spring.
Phantom – Similar to Limelight but with color changing blooms that start in mid-summer as greenish white then gradually change to a blushing pink as summer transitions into fall. Phantom also grows in full sun.
Seaside Serenade Series by Monrovia – A more compact form of hydrangea ideal for smaller areas that blooms on both last year’s growth and new growth.
Pruning Hydrangeas
Most gardeners feel uncertain and confused about when and how much to prune hydrangeas. The truth is most hydrangeas do not need to be pruned at all. Occasionally you may need to prune for shape or size, or remove some dead wood, but most seasons pruning can be skipped.
It is common to have some branch die back after the winter in our area. A common mistake is to get in a hurry when pruning back the winter damage. Be patient, don’t get in a hurry to remove dead branches. Wait until late April or even early May before pruning off the dead branches. Pruning earlier, or pruning to the ground in the spring, could reduce or eliminate blooming this season. When it is time to prune back the dead ends, make your cuts at an angle just above the highest green bud.
When more pruning is required, it is important to know the type of hydrangea you have to know the right time to prune.
Bigleaf, Mophead, French Hydreanes. They bloom once per season in the early summer on old wood, meaning their buds are formed on last year’s growth. Pruning should be done during the summer. If they have become overgrown, remove up to ½ of the total stems by cutting them all the way to the ground. The plant will produce strong new stems that will flower next season. Nikko Blue is an example of this type of hydrangea.
Smooth Hydrangeas. They bloom on new wood, meaning buds are formed on new growth in the current season. Pruning should be done in late winter to early spring. Older smooth hydrangea varieties can become floppy and unruly. Don’t be afraid to prune this variety aggressively. Annabelle is an example of a smooth hydrangea.
Panicle Hydrangeas. They also bloom on new wood. Panicle hydrangeas rarely need to be pruned. But, if they were overgrown last season, prune up to 1/3 of the plant before they leaf out to create a more compact, rounded shape. Limelight is a panicle hydrangea.
Oakleaf Hydrangeas. Oakleafs like to be left alone. Pruning should be limited to removal of dead or broken branches. They bloom on old wood, so if there is a need to prune to improve the shape of the plant, pruning should be done in the summer after it finishes flowering.
Reblooming Hydrangeas. Hydrangeas that bloom on both old and new wood. Early in the season they bloom on the old wood from last season. During the current season they bloom on current season growth. All they really need is deadheading of spent flowers and removal of dead stems. The Endless Summer and Seaside Serenade series are examples of reblooming hydrangeas.
Reblooming hydrangeas last June at the Dallas Arboretum.
Wait until late April to early May to prune the dead from your Endless Summer Hydrangeas.
Oakleaf Hydrangeas rarely have winter die back and are best left alone.
Leaving faded blooms on hydrangea will add interest changing color as they fade.
Deadheading Hydrangeas
Deadheading is the practice of removing spent blooms. You can deadhead hydrangeas, but you don’t have to. Deadheading can increase blooms but is mostly done to keep the plant looking neat. Some gardeners like to leave spent flowers on the plant for seasonal interest as they will change color as they fade. If you do deadhead, prune right above the first set of leaves below the spent flower. Cutting lower will remove emerging buds.
If you don’t deadhead your Endless Summer Hydrangeas the spent flowers will add color to your landscape in the fall. This is the Endless Summer Hydrangea in front of the Hall | Stewart office last October.
Planting Hydrangeas
Hydrangeas prefer rich, well drained soil in a location with morning sun and dappled to full shade in the afternoon and evening. The exception is the Limelight Hydrangea which can be planted in full sun. When planting in our tighter clay soil, start with a hole twice as big as the plant container. Incorporate compost and peat moss into the existing soil, fill the bottom of the hole with enough soil that the root ball will be slightly above the existing grade. Backfill around the root ball with the remaining mix of soil and amendments creating a ring outside the root ball creating area to retain moisture when watering.
Hydrangea Watering
Hydrangeas require more water in the heat of the summer. They perform best in soil that retains some moisture but does not stay wet. It is common for their leaves to wilt slightly on 90+ degree days and then rebound quickly when watered. A good deep soaking every other day in the summer is enough. A 2” layer of mulch will help retain moisture.
Endless Summer Hydrangeas are usually pink in our soils because of the pH being over 6. Sulfur can be used to lower the pH and turn the blooms blue.
Changing Hydrangea Flower Color
Excluding white hydrangeas and many of the new reblooming hydrangeas, soil is the greatest determinate to whether the flower blooms will be blue or pink. Soil with a pH below 6.0 (acidic) will have blue blooms. pH above 6.0 (alkaline) will produce pink flowers. Adding lime to the soil will change blue blooms to pink and adding sulfur will change pink blooms to blue. Endless Summer has a formulated product called Color Me Pink which adds lime to the soil to produce pink blooms and Color Me Blue which adds sulfur to encourage blue blooms. Similar products are available from Bonide.
Bonus Info: “Why aren’t my Endless Summer Hydrangeas blooming?”
1. Pruning – The most common blooming problem is a result of over pruning and pruning at the wrong time. Remember, it is best to not prune them at all. Really the only pruning recommended is at the beginning of the season to remove the brown stems left from the winter. Wait until late April or even early May to prune and then only prune back to the first bud. During the summer, if you want to you can snip off spent blooms, but it is not required. Otherwise, keep the pruners and shears away from your hydrangeas. And…never prune in the fall.
2. Fertilizer – Hydrangeas needing fertilizer or having been fertilized incorrectly will always disappoint. As mentioned above, they need slow-release high phosphorus fertilizer. If you are using a high nitrogen, low phosphorus fertilizer, you will have lots of pretty leaves and no blooms. Just remember – use a fertilizer with a low first number and a high second number.
3. Water – The right amount of water will make a difference. You don’t want the plant to be too wet or too dry. It is ok if they droop in the afternoon heat, but if they are still droopy in the morning, they need a good watering.
4. Sunshine – Hydrangeas bloom best planted in morning sun with dappled afternoon shade. When planted in a hot location such as on the south or west sides of a structure, they need to be protected from the scorching afternoon sun. The bottom line is you don’t want them to fry, and you don’t what them to go without some sun.
5. Soil Problems – What you plant your hydrangeas in will impact the results. Hydrangeas require well drained soil with a good amount of organic material. In our native soils, it is best to adjust the soil when planting with ample amounts of pine bark, peat moss, and/or pecan hulls.
This Endless Summer Hydrangea was added to the landscape last spring and the homeowner was rewarded with extra large blooms this June.
I believe that there is a hydrangea just right for nearly every landscape.
Yes, they require a little more work when planting, and a little more attention to water, but otherwise they are not near as fussy as you would think.
Survey your landscape.
Pick a spot.
Take a trip to a landscape nursery.
Select the perfect hydrangea for your landscape.
It’s worth a try!
Lorne Hall
Hall | Stewart Lawn + Landscape
(405)367-3873
