Ornamental Origanums - the Heat Beaters
Once summer has ticked past its midpoint and temperatures soar the perennial garden starts to buckle and bend. Where there were vibrant colours and burgeoning green only a few weeks before the beds now take on the complexion of a fading beauty. Flowers bleach to a feeble parody, foliage dims to a thatch of brittle, dry stems and flagging leaves, and it seems there's not much we can do about it except watch, and wait it out for those first reviving showers of autumn.
For those among you who want to defy the odds and fight back then look no further than origanum. These hardy plants can not only withstand this withering blowtorch but indeed thrive and can be used to great effect against the tyranny of high summer. They can also be grown in a variety of settings including, window boxes, containers or rock gardens and are perfect for dryland gardens. Indeed my lower rock garden has been a blaze of colour for months without either a jot of help or a drop of water
Origanums belong to the prodigious mint family, Lamiaceae, and like the rest of their kin they are strongly aromatic, have rounded leaves held in pairs and tend towards being spreading and sprawly. Culinary oregano, Origanum vulgare, spreads rapidly like mint and can become invasive but the much prettier ornamental varieties are better mannered, and while they will expand and gently seed around (and who wouldn't want them to?) they never become territorial thugs
While much of the gardening focus has been on a delightful band of hybrids one should never neglect some of the more interesting and little known species. Perhaps the best known of these, and certainly the most famous, is Dittany of Crete, Origanum dictamnus. This plant grows only in the gorges and ravines of the high mountains of Crete and has been known since ancient times for its therapeutic, erotic, and even magical powers. According to legend, the Roman Goddess, Venus, used Dittany from Mt Idi to heal her mortally wounded son, Aeneas during the Trojan War and it is said that shepherds learnt of its power from the Kri Kri, the island's wild goat, which sought it out when sick or wounded. It has always had a reputation as an aphrodisiac, which is probably why it has been harvested almost to extinction! And as the herb of true love: it only grows on cliffs and young men would risk life and limb to harvest some to present as the ultimate love token to the woman they loved. It is a very attractive ornamental easily recognised by a distinctive, soft, grey-white haze covering its stems and leaves, giving it a velvety appearance. During summer and autumn the entire plant lights up with a swathe of coral pink and purple "flowers" that hang from wiry stems like delicately layered earrings. Finding dittany for sale in nurseries is almost as difficult as finding it in the wild but thankfully here in Australia we have David Glenn's Lambley Nursery listing it occasionally, along with some others.
Origanum amanum from eastern Turkey is very similar and equally attractive species and another of the "woolly leaved" group. It is slightly larger in size and shrubbier in habit than O. dictamnus and has larger, tubular lilac flowers which arise from pink-tinged paper bracts. (While we're on the subject of origanum flowers perhaps a little clarification: the true flowers are usually fairly tiny and are snuggled in between the folds of a series of modified leaves, or bracts, at the end of each stem, and it is these bracts, which are often highly coloured and much more ornamental, that "stand in" as flowers}.
I have a plant that appears to be midway between the two aforementioned. Its leaves are less wooly, it has more flowering stems and longer, more intensely coloured flowers. I believe this to be Origanum tournefortii, another native from Crete and some of the islands beyond. (By the way, for those who like to know these things, plants covered with woolly, densely cottony hairs are called lanate).
Once established the "Woolies" are practically indestructible, even on the driest sites, and their velvety, almost ghostly appearance is an added ornamental bonus. However, they are difficult to propagate, and at the first hint of over-watering they will rapidly exit the garden never to return.
Origanum rotundifolium was discovered in the Amanus Mountains in southern Turkey by Peter Davis and later by John Watson, a botanist from Wisley, who was involved in a series of expeditions there in the late 1960s. This species has very large, hop-like bracts which give the flower heads that extra bling and its introduction opened the door to the possibility of new garden plants carrying that trait But something had to happen first .... and that turned out to be a happy accident.
Back in those days there was a LOT of collaborative effort between academic/research institutes, like Wisley, and the nursery trade and newly discovered plants were often “lodged” with excellent growers, who had a good track record, to maintain them and discover if they could be propagated. So it was that O. rotundifolium was given to Elizabeth Strangman of Washfield Nursery where it crossed with another species, Origanum scabrum. This was all very serendipitous and random (I kinda like that) and the result was the very highly regarded, O. "Kent Beauty", which has gone on to win a swag of awards, including the Royal Horticultural Society's Award of Garden Merit, as well as become one of the most successful garden plants of the past decade.
"Kent Beauty" makes an attractive low trailing mound of powdery blue-green leaves that when crushed exude that familiar tangy oregano scent but it is its large, showy, shrimp pink and cream tinged flower heads plus the fact that they completely cover the plant for the entire summer and autumn that is the killer combination. This set the scene for a new line of breeding which has given rise to other extremely attractive garden varieties, including "Barbara Tingay", a similar variety with neater and more richly coloured pinkish-lilac flower heads, and the less well known "Birch Farm", which is more erect with even larger bracts. An incredibly vibrant and richly hued variety, bred by yours truly, has only just been released in Australian and New Zealand with Japan to follow during the Northern spring. Its name is "Bellissimo" and is distributed by Plants Management Australia (PMA) so keep a look out for it. You won't be disappointed.
Ornamental origanums have many virtues: they are without doubt one of the best dryland perennials on the face of the planet and can be grown without water for extended periods. They are pest and disease free so no expensive follow ups or makeovers. Wildlife will not eat them so it's a good ploy to plant a few of them in and around bulb plantings. They have an incredibly long flowering period and their flower heads retain perfect colour long after they are picked so they make excellent subjects for dried flower arrangements. Unlike their culinary cousins, they are neat and well behaved, making gently expanding clumps that can be easily cut back, and in the winter these can be lifted and divided to increase their number. A modest quantity of self-sown seedlings will occur and rather than a nuisance these should be regarded as a gift .... for who knows .. any one of them could turn out to be the next "Kent Beauty"!