Incrediball Hydrangea: A Gardener’s Guide


The Incrediball Hydrangea is a spectacular, low-maintenance flowering shrub for the home landscape. This improved version of the classic Annabelle Hydrangea is the secret to adding striking white hydrangea blooms to your garden (even in cold climates) without signing up for a lot of extra work.

Reasons to Grow Incrediball Hydrangea:

  • Easy to Grow
  • Fast Grower
  • Attractive Foliage
  • Enormous Flowers
  • Strong Stems Hold Up Large Flowers
  • Reliable Bloomer (Flowers on New Wood)
  • Long Blooming
  • Good Cut Flowers and Dried Flowers 
  • Fragrant
  • Low Maintenance
  • Cold Tolerant
  • Native to North America
  • Consistently Named a Best Seller by Proven Winners

Read on to learn more about Incrediball Hydrangea.

All About Incrediball Hydrangea

The perfect white hydrangea for northern gardens? Incrediball is as gorgeous as it is easy to care for in it’s growing regions of Zone 3-9. Native to North America, these shrubs can produce flowers up to a foot across once they’ve made themselves at home in your garden. The blooms open a pale green colour, fading to white as the summer draws to an end. 

All these plants really require is an early spring pruning followed by frequent watering throughout the growing season. They can of course be fed with organic fertilizer and otherwise fussed over, but they are among the easiest hydrangeas to grow. And for minimal effort, you get hophead-type blooms without having to protect the shrub from the winter cold.

Another feature of the Incrediball Hydrangea is that it flowers on new wood. Some hydrangeas flower on old wood and some flower on wood grown earlier in the same year. Hydrangeas that flower on old wood actually grow their flower buds at the end of the summer and keep them over winter in preparation for next year. In some climates, however, the cold weather can kill the whole stem during wintertime…resulting in no flowers the next summer! It’s such a shame when that happens. Because Incrediball flowers on new wood, buds grow in the same year that they bloom. This makes smooth hydrangeas like Incrediball much more reliable to flower than mophead-types in colder zones.

Incrediball has dark green foliage and large creamy-white rounded blooms. The flowers are a light green as they first open (similar to Limelight). The flowers then turn white for several weeks before they start to fade in the fall. Flowers turn brown after a hard freeze or frost. Smooth hydrangeas like Incrediball do not change the colour of their flowers with different soil pH adjustments.

Incrediball Hydrangea in Fall
Here is bloom on an Incrediball Hydrangea in mid-autumn. It’s been on this plant for months and still has a wild beauty to it.

Incrediball Hydrangea Care

The Incrediball Hydrangea is easy to care for. This shrub thrives in sunlight and moist soil. It’s happy in both full sun and part sun, but will struggle in the shade (less than 4 hours of sunlight per day). Like it’s mother variety Annabelle, the Incrediball Hydrangea does best in ground that is consistently moist, but not totally saturated. The roots need air too! These shrubs do best with consistent irrigation. A thick layer of mulch on the soil surrounding the plant will also reduce watering maintenance requirements. 

Incrediball Hydrangea Planting Guide

Planting Incrediball Hydrangeas is best done in early spring or early fall. I’ve had the best transplanting experiences with early fall planting, but the availability of these popular plants is generally better in the early spring (before all the nurseries sell out of them!). It’s nice to find the shrubs as they’re just thinking about waking up from winter dormancy. 

These shrubs are fairly hardy, and even midsummer planting is possible if the soil is kept consistently moist. I had one midsummer-planted Incrediball Shrub experience transplant shock and fail to flower that summer or the next summer. But it did live…it’s growth has just fallen behind the others.

Speaking of growth, consider the size of the full-grown shrub when planting Incrediball Hydrangea. In good conditions, Incrediball reaches a full mature size of 5 feet high by 5 feet wide. New shrubs have a moderate growth rate. It’s not particularly slow growing or fast growing in most conditions. 

I’ve seen my own Incrediball Hydrangeas grow quite quickly with a steady stream of drip line water and a nice blanket of mulch to stabilize soil moisture. The growth rate also seems to be quite affected by sunlight. Shrubs in the shade certainly don’t grow as fast (or flower as much) as shrubs that receive at least 6 hours of sun per day. Plant them somewhere where they get at least 6 hours of sunlight a day, but also where the soil can be kept consistently moist.

Soil Preferences of Incrediball Hydrangea

The Incrediball Hydrangea prefers well-drained soil. This means that it will be happiest in something like sandy loam. A heavy clay soil is not going to grow the healthiest specimen, although it might struggle along just fine. If there is a chance to improve the soil in the area before planting, consider that opportunity carefully. Soil that stays wet (doesn’t drain) can cause root rot in hydrangeas. The roots need air as much as they need water. O

Other than poorly-drained heavy clay soil, these plants are very tolerant of different soil conditions and generally don’t require any soil improvement at all. Incrediball shrubs like soil pH to be slightly acidic. Again, this isn’t a deal-breaker (just a preference). What they do love is soil that is nutrient rich. Well-drained soil can loose nutrients as water drains through, so the addition of quality compost or organic fertilizer can help boost soil nutrients.

Mulching Incrediball Hydrangea Plants

A thick layer of organic mulch is a very important aspect of caring for Hydrangea “Incrediball”. While these plants like sun, they NEED consistently moist soil to thrive. Use a rich organic mulch like homemade compost. Do not let moisture-loving mulch like shredded bark touch the stems of the plants. Always keep mulch 6” back from the stems of shrubs and trees. The stems and trunks of these woody plants is adapted to do best with adequate airflow.

Sunlight Requirements for Incrediball Hydrangea

Searching out a sunny spot is a key planting tip for Incrediball Hydrangea. Incrediball hydrangea grows best in full sun to partial shade. Try to find a spot where it will get at least 6 hours of sunshine. If you’ve got a choice, morning sun is preferable to afternoon sun (though not at all a deal-breaker).

Years ago I had a notion that because hydrangeas enjoyed consistent soil moisture, they must love shade. I was so wrong. The Incrediball shrubs I have in the shade are clearly not as happy as those in full sun. The shady shrubs have grown long and leggy, literally reaching out to find a bit of sunlight. The ones in the sunny areas are happily growing into rounded shrubs with stronger branches.

We live in zone 5, where winters are cold and summers are hot. In our northern zone, Incrediball does well in full sun all day. In southern climates, shade from the blazing afternoon sun would be preferable. Morning sun just seems to be so much gentler on these shrubs.

While these shrubs do like sunlight, they’re not total sunbathers. These are not the right shrubs for dry, exposed locations. Moist soil that rarely dries out will produce the healthiest plants. Take the time to select a growing location that gets adequate sunshine, but where the soil can also be kept moist.

Watering Requirements for Incrediball Hydrangea

Watering for Incrediball Hydrangeas is best done with a watering system. These plants love consistently-moist soil. The digital timer of a DIY drip line irrigation system can keep up with frequent watering without becoming a burden on your yard work schedule. A drip line also waters the plants directly from the soil. Watering Incrediball Hydrangea from above is discouraged as the water can weigh down the enormous flowers and cause the stems to flop over. Not good! Water the soil at the base of the plant (not the foliage).

While they won’t love it, smooth hydrangeas will often survive droughts. These are native plants that are well-adapted to the climates of the North American East Coast. Their leaves may droop during hot, dry spells, but they won’t be the first plants to die during a drought. Keep on the lookout for droopy leaves and increase the frequency of the drip watering timer in dry spells. If these hydrangeas are left to totally dry out, they may not survive.

Growing Temperature Climate Range for Incrediball Hydrangea

Incrediball Hydrangea grow in zones 3-9. At the colder end of this range, it’s wise to search out a warm microclimate protected from the worst of the winter harshness. At the hotter end of this range, it’s wise to seek out a spot where the plant is sheltered from the hot sun in the afternoon. Because Incrediball flowers on new wood, it is a reliable flower producer even in summers after particularly cold winters. 

Summer and autumn rains can sometimes weigh down the flowers of Incrediball and cause the stems to flop over towards the ground. This generally happens with recently-planted shrubs or particularly leggy specimens. Resist the urge to prune the whole plant back to the ground in the off-season. Prune instead to create a strong framework of woody stems to hold up years worth of enormous blooms (more on that below).

How to Fertilize Incrediball Hydrangea

Fertilize Incrediball Hydrangea plants with a slow-release granular organic fertilizer in the springtime. Slow-release fertilizer can be applied in early spring. The best time to fertilize is after the ground thaws and before growth really starts getting going. 

If you’ve missed this window – that’s totally ok! Organic fertilizer can be applied to these shrubs until summertime. I would limit fertilizing in August-October to a top-dressing of homemade compost. Save the concentrated organic products for springtime use.

Here are a few fertilizer options that work well for Incrediball Hydrangeas:

It’s also totally fine to use an all-purpose natural fertilizer! Check out my favourite overall plant foods on this page.

Deadheading Incrediball Hydrangea

Incrediball Hydrangea Pruning

Incrediball is an easy hydrangea to prune. Prune it once a year just before it starts growing for the season. Each stem just needs to be shortened. It’s also nice to shape the bush into a round shape. Avoid cutting the whole plant back to the ground level. Let it grow a permanent framework of branches to hold up its heavy flowers. 

Dead, damaged, or diseased stems should be removed right to the ground whenever observed (no need to wait until the plant is dormant). It’s also fine to trim the plant a bit for shape throughout the summer. A bit of late-summer pruning isn’t going to send it into growth overdrive if the nights are starting to get longer and colder. Check out this helpful article from The Garden Professors for proper instruction on late summer pruning.

Prune Incrediball Hydrangea shrubs in late winter or early spring. Use clean, sharp hand pruners to trim back each branch on the shrub. I start by removing the end of each stem. I’ll use my pruners to take of 1/3 of the length of each branch. Once each branch has had a bit of a haircut, step back and look at the general shape of the plant. Make any adjustments to encourage the shrub to grow in a round shape.

Here are some great pruning tips from the grower of this shrub:

As for pruning, cut the entire plant back by about one-third its total height each spring, just as the new growth begins to emerge on stems. This serves to build up a strong, supportive, woody base while also encouraging abundant new growth for plenty of flowers. 

Proven Winners

Encouraging the shrub to strengthen its existing stems year after year is what protects the Incrediball Hydrangea from flopping over under the weight of its own heavy flowers. Do not prune it back all the way to the ground. Let its branches mature into a strong foundation for holding up lovely big white hydrangea flowers every summer.

Pruning in late winter or early spring encourages strong growth of stems and production of flowers. Unlike true mophead hydrangeas, Incrediball (which is actually a smooth hydrangea) flowers on fresh new stems. Pruning at the very start of the gardening season won’t remove any existing flower buds, but it will encourage buds to grow in the springtime.

Timing pruning at the start of the season also allows gardeners to keep the spent hydrangea blooms on the branches over winter. These plants are stunners, even in the winter! Their spent flowers provide visual interest in an otherwise bleak winter garden. They’ll be a tan colour instead of white, but this just makes them stand out against the snow. Spent flower heads can also look interesting in freeform flower arrangements over winter.

I also trim off any stems that are crossing other stems and growing in the wrong direction. The stems should each have some room to grow and hopefully not be rubbing on each other.

Incrediball Hydrangea in Fall After Frost

Deadheading Incrediball Hydrangea

Do Incrediball Hydrangea flowers need to be deadheaded? The flowers of Incrediball Hydrangeas do not need to be deadheaded (cut off) during the growing season. You certainly can deadhead the flowers off this shrub, but it’s not required. This is a hardy, tolerant shrub. Cut off the flowers whenever you wish.

Cut flowers for arrangements throughout the season. It’s nice to bring some inside the house during the summer or give them as gifts. If flowers are cut off early in the summer, the shrub may flower again that year. I also deadhead any flowers that have totally flopped over. This was more common when the shrubs were first planted, and is less common now that a strong framework of permanent branches is required.

Incrediball Hydrangea Fall Maintenance

Incrediball Hydrangea plants do not require any special winterization tactics. As with other shrubs, remove any branches that are dead, damaged, or diseased. I usually remove them all the way down to the base of the plant (assuming there are few of them). Rake up fallen leaves and ensure that the stems have air circulation. 

The flowers can be left standing on the Incrediball Hydrangea over winter. They provide lovely winter interest in the garden. Seed capsules will form in late fall and be a draw for beneficial wildlife. They’re also just pretty!

Incrediball: A New Smooth Hydrangea (The Improved Annabelle)

The first Incrediball Hydrangea was bred at Spring Meadow Nursery in Michigan in 2002. https://springmeadownursery.com/about/our-story/

It was developed from the Annabelle hydrangea, which was originally found in the wild near Anna, Illinois. Spring Meadow Nursery has been propagating and distributing Incrediball Hydrangeas for the Proven Winners brand since the companies joined forces in 2004. 

Incrediball is the consumer trade name for the named cultivar “Abetwo” of Hydrangea arborescens, sold by Proven Winners. Abetwo/Incrediball is the product of an open-pollenated cross of the mother Annabelle and pollen from an unknown male variety. As it is a descendant of Annabelle, the Incrediball Hydrangea is often referred to as the Improved Annabelle. Incrediball was chosen over other descendent plants because of it’s strong stems and large mophead-type flowers. 

Incrediball Hydrangea is a new cultivar of Smooth Hydrangea. Smooth Hydrangea (Hydrangea arborescens) is also called Wild Hydrangea, as they are native to North America. The species Hydrangea arborescens grows wild along slopes and streams in Eastern USA. These easy-to-care-for native deciduous shrubs are winter hardy in growing zones 3 to 9. 

Further Reading: Here are the Plant Breeder’s Rights for this named cultivar, which include interesting breeding history.

Hydrangea Incrediball vs. Annabelle

Hydrangea Incrediball is a child variety of Hydrangea Annabelle. It therefore shares many characteristics with Annabelle, but is it’s own unique plant. The flowers are the same colour, the leaves are the same colour, but there are a couple important structural differences between the two hydrangeas:

The two benefits of Incrediball over Annabelle are as follows:

  • Incrediball has stronger stems than Annabelle Hydrangea
  • Incrediball has larger flower heads than Annabelle Hydrangea

Incrediball Hydrangea is essentially an improved version of the Annabelle Hydrangea. Improving on Annabelle was likely, as Annabelle is actually a wild cultivar (was found in the wild, not bred in a nursery). Even though Incrediball has larger flowers than Annabelle, the flowers are less likely to droop because the stems are so much stronger. Droopy flowers is a common complaint of Annabelle Hydrangea, and the Incrediball cultivar is certainly an improvement in this characteristic.

Newly Planted Incrediball Hydrangea - Improved Annabelle
Here is a small Incrediball Hydrangea after planting. The flowers on new shrubs are small – that is normal! Give the plant a few years to get established. With proper sunlight, water, and drainage the bloom size will increase steadily.

Garden Design with Incrediball Hydrangea 

The Incrediball Hydrangea was bred to be a stunner in home gardens. It’s easy to grow, flowers reliably, produces giant booms, and has a lovely fragrance. It’s as pretty in the garden as it is in fresh bouquets and dried flower arrangements. It’s nice to have a plant in the yard that flowers later in the summer after all the perennial flowers seem to have faded away.

The mature size of Incrediball Hydrangea is a height of 5 feet and a spread of 5 feet, with a rounded shape. In less-than-perfect growing conditions, it may only reach a size of 4’ tall by 4’ wide. These are small shrubs in comparison to other types of hydrangeas, making them great for residential yards and mass plantings.

Here are some ideas for adding Incrediball Hydrangea to your garden design:

  • Border
  • Hedge
  • Mass Planting
  • Specimen
  • Container
  • Cutting Garden
  • Rain Garden
  • Native Plant Garden
  • Pollinator Garden
  • Wildflower Garden
  • Woodland Garden

Incrediball Hydrangea Flowers

Incrediball Hydrangea produces large flowers which start out a light green colour. The flowers mature to cream and then to bright white. After about 3 weeks at bright white, the blooms fade to tan. A freeze or hard frost will turn exposed flowers brown. The seed heads can then be observed forming.

The bloom time of Incrediball Hydrangea is July-September in most areas. The true bright white period of the flowers will vary – even a single shrub may have flowers at different stages of maturity. August is generally the best time for cutting the bright white bloom specimens.

The flowers of Hydrangea Incrediball are enticing to beneficial wildlife such as bees and butterflies. Local pollinators will frequent your yard to visit this shrub. These shrubs produce larger flowers when sited in full sun. Fortunately the bees and butterflies don’t seem to mind snacking in full sunlight! A shallow dish of water and pebbles nearby your shrub will help attract bees and butterflies.

Incrediball Hydrangea Spacing

Incrediball Hydrangeas generally grow to a width of 5 feet. For a compact hedge, space the plants 4 feet apart (centre from centre). Measure from the centre base of the stem rather than the edge of the branches. They can be planted up to 6 feet apart to maintain a similar linear visual effect with a lower up-front cost.

Incrediball Hydrangea Companion Plants

Here are some lovely companion plants for the Incrediball Hydrangea

  • Peony
  • Daylily
  • Ornamental Grasses
  • Boxwood
  • Lilac

Common Problems with Incrediball Hydrangeas

Hydrangea is susceptible to certain woody plant diseases such as powdery mildew. Prune any affected branches down to the ground as soon as observed. Dispose of in the fire pit instead of the compost (unless you’re sure you can hot-compost it). Watch for pest insects such as aphids. Aphids can usually be sprayed off the plant with plain water if caught early.

Both Annabelle and and its child variety Incrediball can experience flopping flowers. Follow the pruning instructions above to create a strong permanent framework of branches. This will take a few years. Avoid pruning it back to the ground.

Lack of blooming in Incrediball Hydrangea is the result of less-than-perfect environmental conditions. Ensure the plant has well-drained soil. Sandy loam is preferable. Fertilize with a quality organic fertilizer in the early spring. Ensure the soil is kept consistently moist throughout the growing season. Most importantly, ensure the plant is getting at least 6 hours a day of sunshine. A lack of light can drastically affect the blooming of this hydrangea. Let the light into the area or consider a more suitable location for the plant.

Mary Jane

Mary Jane is a home gardener who loves creating healthy, welcoming spaces (indoors and out!) - About Mary Jane (https://www.homefortheharvest.com/authors/about-mary-jane-duford/)

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