Osmanthus heterophyllus

Osmanthus is a genus of only about 15-20 evergreen species and varieties, and a genus which I fell in love with the first time I saw a few plants of. Their leathery and sometimes spiny leaves resemble hollies but osmanthus plants have something extra which gave them their name derived from Greek: osme = fragrance and anthos = flower. Osmanthus has tiny but highly fragrant flowers. I was an amateur when I bought the first plants and I had no idea that in all encyclopedias they were rated too tender for our C.E. climate. And since I never knew I put them to my garden. And after some 15 years of growing I can assure you that all of them not only survived even the worst winter of 2006/2007, they thrive and some of them are taller than me and I am very close to 2m. Including the most tender one o.fragrans. I keep on trialling more species and varieties because I noticed that they have some genetic predisposition for extreme drought tolerance in summer and some are even happy with dry soil in winter. And with current lack of precipitation we will need more of drought tolerant plants.

Holly osmanthus or false holly is a taxon of evergreen shrubs and small trees native to East Asia, southern Japan, and Taiwan. The species bears evergreen, leathery, dark green, highly glossy, and thorny leaves, which resemble hollies, but something seems to be wrong for the more experienced eye: holly leaves are alternate while osmanthus leaves are opposite. Perhaps a negligible detail for someone, but this detail strongly characterizes the architecture of the branches as well as the whole plant. In autumn it blooms profusely with tiny, sweetly scented, snow-white flowers. If pollinated by a male plant they are followed by small, purplish black, non-toxic berries, but that happens rarely.

It naturally forms upright, slow to medium-fast (20-30 cm per year) growing shrubs of loose, somewhat irregular habit getting rounded with age, which can be easily maintained and shaped by pruning. Spring pruning enhances branching, summer trimming is great for shaping. The presence and quantity of thorns as well as the size of the leaves may vary with each clone and significantly decreases with age, i.e., mature plants have almost entire, camellia-like foliage. The twigs and bark are light gray and smooth.

Spine-leaved osmanthus has long been used as a natural barrier against wild animals and cattle. Another important advantage is that they are long-lived shrubs or trees, and we are not talking about decades but hundreds of years. There are records of specimens whose age was estimated to 950 or more years. In other words if located in an ideal spot it can be a plant that will be passed on by one generation to another. It looks great as an attractive evergreen specimen shrub or small tree, and does a good job as a hedge, too.

Grow osmanthus in moist but well-drained, humus rich, preferably acidic soil. Provide plenty of mulch for winter to protect the roots from fast freezing. It loves full sun but in colder regions find it a location sheltered from late winter and early spring sunlight but with plenty of light during the growing season. Use only plants with mature wood in zone 6 and transplant it no later than late summer in order to avoid frost damage after the first winter. It is perfectly hardy to -20 °C without damage, and to -24°C (USDA zone 6) with some sunscorch. It will withstand a few degrees lower with some wood damage but regenerates readily after spring pruning. It does not suffer from diseases, but vine weevil can be a problem.

Last update 11-03-2022