Epigenetics is a scientific field in high fashion and moving fast nowadays. Although the term was coined in 1942 by C. H. Waddington and scientists have been working since to elucidate the mechanisms involved, it is only recently that the mainstream media has been inundated by articles on epigenetic themes.

Very concise and without details, the field of epigenetics deals with the modifications induced by various external factors on any given organism and their consequences. The actual genetic making of the organism is not changed; epigenetic modifications only affect how various genes are expressed and are switch on or off  (“epi” means “above” in Greek hence the epigenetics = factors beyond the genetic code. Most importantly, some of these changes can be inherited from a generation to another.

Referring strictly to plants, the study of epigenetics is underway and there is still much to learn.
I’ve read that “Plants are masters of epigenetic regulation” and it is not hard to understand why: they cannot move, so they have no choice but to adapt continuously to the changing environment and other stimuli.

Silene compacta in habitat

On a practical level, we can speculate that the epigenetics explains why some species and especially those living in extreme habitats (alpine regions, deserts…) are some of the hardest to adapt to garden cultivation even when provided with close by conditions.
Also, epigenetics might explain the differences in germination patterns of a given species, in case of mother-plants originating from different geographical areas.

It is already known by gardeners that the more different your climate & garden conditions are than the ones where a species grows wild, the more difficult it will be to ‘tame’ it into cultivation and hardiness is not the only factor.
The first generation of seedlings express the traits inherited from the mother-plant and they react accordingly in relation to seasonal temperatures, substrate, light intensity, water regime…..

By growing a second generation seedlings from the first ones, and then a third one and so on….we have increasingly higher chances to obtain better ‘tamed’ plants for our specific garden conditions. They will look exactly the same as the original mother-plant, but their adaptation to the local variations in temperatures, water regime, humidity and so on, will be improved.

To exemplify:
Last summer, Helichrysum arenarium (sandy everlasting) successfully flowered in my rockery and set a few seeds; later in the fall it ‘disappeared’ despite growing in a very well drained spot.

Helichrysum arenarium ex. Dobrogea,  flowering in August, 2021

The species was grown from wild collected seeds in the Dobrogea region of Romania, which has a very different climate than we have in SW Ontario, so it was no big surprise that it didn’t last long.

It is a very lucky situation when a few seeds are available to obtain a second generation of seedlings. There is hope that they will adapt better to the new environment in the next generation.

Other species also managed only a first flowering: Paronychia cephalotes, a couple of Minuartia and Centaurea jankae.

But others grown from seeds from the same trip adapted well: Dianthus nardiformis, Centaurea orientalis, Alyssum borzeanum, Aurinia saxatilis, Sedum urvillei, Silene compacra, Ephedra distachya and Iris suaveolens.

Virtual traveling to the region in question available below:
Winter getaway  – Dobrogea I
Winter getaway – Dobrogea II

And/or read more about epigenetics in plants (there are many other articles available).
Epigenetic Regulation in Plants

Epimedium grandiflorum arrived in Europe, in Antwerp, with Philipp Franz von Siebold’s plant collection from Japan, in 1830 according to some reports. Actually, during his 8 years in Japan, Siebold sent three shipments with an unknown number of herbarium specimens to Leiden, Ghent, Brussels and Antwerp. The important thing is that among them there were 2 plants of Epimedium grandiflorum, one with white flowers, and one with pale-violet flowers. They were planted at the Ghent Botanical Garden. Unsurprisingly, the large spurred flowers received a lot of attention because the only species of Epimedium known at that time was E. alpinum, which has small flowers. The Japanese name of E. grandiflorum – ikariso, comes from: ‘ikari’ – anchor and ‘so’- plant, the four long curved spurs of the flowers suggesting the four-claw anchor used by Japanese fishermen.

Epimedium grandiflorum ‘Purple Prince’

Epimedium grandiflorum spread rapidly into cultivation. Currently, there are countless varieties of this species, and it has also contributed as a parent of some important hybrid groups such as E. x rubrum, E. x versicolor and E. x youngianum. It has three recognised forms today: f. grandiflorum, f. flavescens and f. violaceum.

Epimedium sempervirens ‘Variegatum’

Epimedium sempervirens, resembles very much E. grandiflorum with the exception of the evergreen leaves and of a more elongated rhizome. It is endemic to the western side of S. Honshu. E. sempervirens has crossed with E. diphyllum in the wild to produce the white flowered E. setosum. I already featured the sweet E. sempervirens ‘Candy Hearts’ in ‘Plant Valentines’, and now the answer, if someone was asking – yes, there is a variegated Epimedium, see illustrated E. sempervirens ‘Variegatum’.

Epimedium diphyllum is actually the first Epimedium that arrived in Europe from Japan, sent by Franz von Siebold to Leiden. From there it spread to other botanical gardens and nurseries in England. A small and dainty species, today is known more in cultivation through the garden hybrids that belong to E. x youngianum. The name E. x youngianum is used to include all the garden hybrids between E. diphyllum and E. grandiflorum. The numerous varieties that exist in cultivation exhibit usually intermediate characteristics between the parents. In the wild, the same combination of parents lead to a new species: E. trifoliatobinatum.

Epimedium x youngianum ‘Beni-Kujaku’

Besides these, there are many Japanese hybrids of unknown parentage. They can vary greatly in their flower shape, size and colour. Japanese Epimediums have the same requirements for cultivation as the Chinese ones, with the only difference that they prefer a slightly acidic substrate. Using a fertilizer for acid-loving plants would probably give better results, especially if the irrigation water is alkaline. 

Epimedium 'Sakura Maru'

Epimedium ‘Sakura Maru’

If you didn’t get ‘hooked’ yet on the Chinese Epimediums I’m sure now is the moment.

There are so many varieties on the market today and it is hard to choose only a few images to represent the whole range of Japanese Epimediums. The following gallery presents only a few from the many Epimediums that one can see at Lost Horizons Nursery (near Guelph in Ontario).

Non-plants related: David Mitchell’s book The Thousand Autumns of Jacob de Zoet, recreates with authenticity the atmosphere of the nineteenth century Japan, and the life on  Dejima, an artificial island close to Nagasaki Harbor, where Siebold also lived during his stay in Japan around the same time period.