Japanese anemones
Although the progenitors of our garden varieties, Anemone Hupehensis, Anemone Vitifolia and A. Tomentosa, are generally known as Japanese Anemone, in reality they do not originate from Japan but from central and south-western China as well as the Himalaya region. It was Philipp Franz von Siebold who first admired such specimens which had escaped from native cultivation and had been re-naturalised in a foreign land. He therefore mistakenly attributed their origins as Japanese.
Japanese anemone spread to Europe in the middle of the 1800s thanks in part to Robert Fortune, the great “plant hunter”, who introduced the A. hupehensis var. japonica to the garden of the Horticultural Society of London. This variety, characterised by tepals which are more numerous and flimsier with respect to the type species, was immediately subjected to cross-breeding on the part of English and French horticulturists. However, it was German plant growers who created, up until the years between the wars, the majority of the varieties we know today. Largely forgotten by gardeners until relatively recently, we are now witnessing renewed interest in these plants thanks to their informal yet elegant nature, highly suitable for a 'natural' garden.
Japanese anemone are perennial herbs growing from rhizomes, with branched stems up to 90 cm tall. They are equipped with basal leaves divided into three segments, and only three or four upper leaves. The flowers are gathered in umbrella-shaped inflorescences and they can have have 5 – 6 tepals which are almost round in the varieties deriving from A. hupehensis, or 20-30 longer and narrower tepals in those deriving from A. hupehensis var. japonica.
Bushes of Japanese anemone remain short and thick until the middle of summer when one begins to pull up the slender, erect stems. Such stems are usually between 60 and 90 cm tall, according to the variety in question, and carry the flowering buds.
The flowers, with a yellow centre constituted by the reproductive organs, are not surrounded by petals as such but by tepals, modified petals coloured by all manner of shades from white to intense pinks, purples and magentas.
After blooming, with the arrival of the cold weather, the aerial part of the plant dries up and the anemone enters into a kind of vegetative hibernation until the following spring when new leaves will sprout and the cycle starts again. This pant is very easy to grow and tends to expand considerably, flowering with greater abundance from the second year after planting on.
Hybrid Japanese anemone are similar to A. hupehensis, but much more robust and usually a good deal taller (up to 140 cm). The first cross-breeders to work on A. hupehensis var. japonica and A. vitifolia were Pfitzer in Germany and Lemoine in France. The numerous hybrids have single or double flowers, with colours that range from white to dark crimson.
Exposure:
these anemone develop best in partially sunlit conditions, although they are not adverse to conditions of semi-shade, especially at more southern latitudes and at warmer times of the year. So as not ruin the flower stalks of the plant, it is advisable to keep them sheltered from the wind. Normally, they are not sensitive to the cold, and even quite severe winter temperatures do not constitute a problem, although in the event of prolonged freezing temperatures in the mountains it would be a good idea to provide them with protection for the first year after planting with a good layer of mulch. If all these conditions are adhered to, anemone often propagate considerably, sometimes too much. However, if the soil is too arid, it is possible that they will struggle or even die. After the first year, there will be no further difficulties with respect to cultivation, and it may even be appropriate to limit the ease at which they spread to the detriment of other plants. We recommend that the older leaves are removed from time to time, and above all the dry leaves at the end of the vegetative cycle.
Terrain:
Japanese anemone prefer neutral or slightly alkaline soils (pH around 7) which are rich, well drained, loose and soft. Nevertheless, they produce an abundance of flowers and they spread with vigour even in less-than-optimal conditions. Before planting them, it is advisable to work the soil and mix in some mature manure and some soft compost.
Watering:
these plants do not need excessive watering, and they can endure brief periods of dryness without any problems whatsoever. Nevertheless, one should remember that in nature they grow in moist soil and have surface roots, and so although they usually receive enough water from rainfall, one is advised to water them during particularly dry periods from March to October. In the winter, the plant enters a state of vegetative hibernation and therefore does not require watering. In the spring, it is a good idea to add some slow-release granular fertiliser for plants that have already flowered, or some well-decomposed organic fertiliser.
Propagation:
Anemone bunches can be easily divided in the spring in order to obtain new plants which can be immediately replanted. Non-hybrid varieties can also propagate through seed transfer at the end of the summer. Young plants should be planted at least one year after germination in order to avoid being ruined by winter conditions when still too delicate. It is also possible to sow the seeds at the beginning of the spring, meaning that the flowers will bloom the following spring. In any case, the little seeds should be kept in a refrigerator for 5 to 6 weeks before being sown.
Parasites and diseases:
anemone are unlikely to be attacked by parasites or disease. In years with particularly humid and rainy summers their leaves and stems may be attacked by fungus, causing the edges of the leaves to curl up and blacken, and the petioles to dry up. This can nearly always be resolved with a couple of anti-botritic fungicide treatments. On occasion, the plant may be attacked by weevils or slugs that feed on its leaves, but this hardly ever causes significant damage. Anemone are always very quick to generate new leaves and shoots, and to replace those that have been eaten.