Hydrangea quercifolia 'HARMONY'

Oakleaf hydrangea is a sought-after flowering plant because it offers many beautiful features at once: unusually shaped leaves, abundant flowering, and attractive autumn leaf colouration. It is native to the southeastern part of the USA and was first described by the American botanist William Bartram (1739-1823) during his botanical exploration, which he conducted between 1773 and 1777 in the area of present-day Georgia. Despite being a very warm location, this hydrangea has demonstrated the ability to survive frosts far further north, down to -30 °C, and some varieties can cope with even harder frost. Its undying popularity is reflected in the new varieties that are still being bred today.

In the world of oakleaf hydrangeas, Harmony variety can be considered a prima donna, as it is one of the few (if not the only one) to offer rounded flower clusters, which are unique for this species that usually produces pointed conical inflorescences. The individual flowers are creamy white, sterile, and bloom approximately from mid-June. They remain attractive on the shrub for several months, turning slightly pink by the end of summer.

The deciduous leaves are large, approximately 30 cm long and wide, deeply lobed, and shaped like the leaves of red oaks or large-leaved maples. In spring, they are bright green, and by the end of summer, they take on brilliant red tones, adorning the plant for up to 2 months. They fall off very late, often among the last deciduous shrubs. The stems have attractive, cinnamon-orange bark that peels off in thin strips, which is particularly beautiful in winter.

The shrubs are compact and dense, almost impenetrable due to the abundance of leaves. They do not require pruning to maintain a nice shape. However, if you wish to shape the plant, do so immediately after flowering to allow it to form sufficiently mature branches that will bloom the following year. To ensure a smaller plant, root pruning is preferred – simply cut the side roots with a spade at a distance of about 25-30 cm from the centre of the shrub, and it will not grow as much the following year.

Native habitat of oakleaf hydrangea ranges from moist meadows to partly waterlogged streambanks where the soil has enough nutrients. Provide similar conditions for it in your garden as well. It tolerates heavy soils well; it just may take a while to establish there. It will be happiest in partial shade, but in permanently moist soil, it will thrive even in full sun. Appropriate fertilization will enhance its beauty, but excessive feeding will result in rapid growth and weak branches. Under good conditions, the plant may produce suckers, but it is very easy to keep in place by their removal which can yield new seedlings for planting elsewhere or serve as a gift to your green-fingered friend. Fully hardy to at least -27 °C (USDA zone 5b).

Last update: 18-04-2008; 27-01-2025