The game species is native to the Appalachian Mountains, a mountain range in the eastern USA that runs in a north-south direction. It also occurs in the river valley of the Delaware River. However, the wild snowball hydrangea does not play a role as a garden plant. We only sell selected garden forms with particularly large, sterile inflorescences.
The most popular is the very large-flowered variety ‘Annabelle’, which according to legend was discovered as a wild plant on a horseback in 1910 by Harriet Kirkpatrick, the then owner of the stoneware factory Anna Pottery in southern Illinois. She planted her find in the garden of the company premises and here the Hydrangea grew unchallenged for 50 years before Dr. J. C. McDaniel, plant breeder and employee of the University of Illinois, became aware of her in the 1960s. He named her ‘Annabelle’ in honour of the company Anna Pottery, which had long since ceased to exist.
The snowball hydrangea is an upright shrub up to two metres high with numerous basic shoots. The twigs are remarkably thin and have an ochre-yellow, later reddish to dark brown bark. Snowball hydrangeas spread underground through short runners, so that old shrubs can take up quite a lot of space over the years.
The light green, opposite leaves are ovate to elliptic and tapered at the end. They are 8 to 15 centimeters long and have a matt surface. The plants throw off their foliage at the end of the season, but do not develop an autumn colouring beforehand.
The large, flat flower panicles are from a botanical point of view so-called umbrella panicles. They appear from the end of June to September at the ends of the new shoots and consist of numerous sterile, initially greenish-white, later cream-white individual flowers. When they wither, they take on a lime-green shade again and are very decorative even when dried up. The variety ‘Annabelle’ is one of the most flowering and large-flowered selections to date – 25 centimeters in diameter are not uncommon for its flowers.
Since the flowers are usually sterile, ‘Annabelle’ and most other varieties do not grow fruit.
Location and soil
Snowball hydrangeas grow in sunny to shady locations, which should be protected from wind and ideally from rain. A larger tree is ideal as a source of shade, which at the same time reduces very heavy rainfall. When it rains heavily, the flowers quickly become so heavy that the flower stems fold and the whole shrub literally falls apart. As a rule, however, after some time, it will straighten itself up again by itself. As with all hydrangeas, the soil should have the lowest possible lime content and be rich in humus, loose and sufficiently moist. A pH value between 5.5 and 6 is ideal.
Planting and care
Snowball hydrangeas are among the most frost-hardy hydrangeas and survive even cold winters without any problems. Therefore, it is not necessary to plant snowball hydrangeas in spring, unlike the more sensitive farmer’s hydrangeas. Also the autumn planting does not cause them any problems. Prepare the soil thoroughly by working in deciduous humus or sand if necessary. Since snowball hydrangeas, like all hydrangeas, have a high water requirement, a slightly shady location is better suited than a full sunny one. In any case, the freshly planted shrubs should always be kept moist for the first few weeks. Mulch the soil with a layer of foliage or bark mulch after having previously sprinkled a few handfuls of horn shavings in the root area.
If possible, do not use garden compost to fertilize snowball hydrangeas because it often contains too much lime. It is best to spread horn shavings in spring or supply the plants with a special rhododendron fertilizer. Hydrangea fertilizer is of course also suitable, but is usually more expensive, as it is often enriched with alum for the blue colouring of farmer’s hydrangeas. However, this has no influence on the flower colour of the snowball hydrangea. In particular, the large-flowered ‘Annabelle’ should be provided with a perennial support in good time. Alternatively, you can also stabilise the shoots individually with bamboo sticks so that they do not bend under the heavy blossom splendour.
In contrast to the farmer’s hydrangea, in which only the old inflorescences are removed, the snowball hydrangea can be cut back at the end of February to just above the ground. They then sprout again particularly vigorously and form large inflorescences. In windy locations, however, you should refrain from a very strong pruning. The long new shoots are not very stable and often leave the flower heads hanging after rain showers. With weaker pruning, the flowers remain somewhat smaller and the entire branch structure is more stable.
The flowering shrubs are usually integrated individually or in groups into perennial plantations in sunny to semi-shade locations. Snowball hydrangeas can be very well combined here with large-leaved leaf ornamental shrubs such as the Rodgersias, with Astilben, Eisenhut, Kugeldistel (Echinops), Hoher Fetthenne and ornamental grasses. In addition, the low shrubs cut a good figure as lush flower hedges.
In the shade they harmonize very beautifully with different ferns. Proven bed partners among the woody plants are, for example, Japanese dwarf spar (Spiraea japonica), dark-leaved fan maples and, of course, all other hydrangea species. Even with yellow or white roses, snowball hydrangeas can be combined in shady locations – and an insider tip as a bedding partner is the variety ‘Rhapsody in Blue’ with its purple flowers. Beautiful contrasts form snowball hydrangeas with strictly cut shaped shrubs such as boxwood – which is why they are also very popular in formal gardens. Snowball hydrangeas are also suitable for pot culture on the terrace or balcony, as they remain relatively compact with a height of around 150 centimeters. However, the pot needs a lot of earth volume so that the earth does not dry out too quickly on sunny days.
Grandiflora’: next to ‘Annabelle’ she belongs to the classics in the assortment, is somewhat more vigorous and stable, but has smaller flowers.
Pink Annabelle’: This is a ‘Annabelle’-like variety with light pink flower balls – the name betrays this. It is also offered under the name ‘Invincibelle Spirit
Strong Annabelle’: It grows more compact, has slightly smaller flower balls than the real ‘Annabelle’ and is therefore considered more stable.
Incrediball’: the variety with the largest inflorescences at present. They reach 30 centimeters in diameter and form a beautiful hemisphere. They hardly differ in colour from ‘Annabelle’, but are a little whiter during the main flowering period.
All snowball hydrangeas can easily be propagated in early summer by half woody cuttings. It is also possible to propagate the plants by using cuttings in winter and even by dividing them – i.e. cutting off the runners in autumn or spring – new plants can be obtained.
Diseases and pests
The snowball hydrangeas suffer less from incurable virus infections than the related farmer’s hydrangeas. Occasionally, leaf spot diseases and powdery mildew occur. Among the most common animal pests are cup scale insects and snout weevils.
I am Don Burke, one of the authors at My Garden Guide. I am a horticulturist that cultivates, grows, and cares for plants, ranging from shrubs and fruits to flowers. I do it in my own garden and in my nursery. I show you how to take care of your garden and how to perform garden landscaping in an easy way, step by step.I am originally from Sydney and I wrote in local magazines. Later on, I have decided, more than two decades ago, to create my own blog. My area of specialization is related to orchid care, succulent care, and the study of the substrate and the soil. Therefore, you will see many articles dedicated to these disciplines. I also provide advice about how to improve the landscape design of your garden.