gardeningblog

Of the thousands of orchid species and cultivars grown worldwide, relatively few are hardy enough to be cultivated outdoors in the UK. And of these, only a handful fit comfortably into the more formal parts of the garden. One such is Bletilla striata.

Such an exotic-looking plant may at first give the impression that it is difficult to grow, but this is far from true. I have grown it at the base of a south-facing wall in very well-drained soil with little organic matter; in a west-facing border where the soil was much richer and where a mulch was applied annually; and in a south-east-facing border in my current garden where the soil is heavy clay. In all three cases it has, or is, performing wonderfully, its flowers usually appearing in June.

So, it seems unfussy as to soil, although I dare say it may not thank you if it were to be planted in a bog. And as long as it gets a reasonable amount of sun, aspect is not too crucial. (I would be glad to hear from anyone who has succeeded with this plant in a north-facing situation or where sunlight was otherwise restricted.)

It has very attractive foliage and, for those of you who appreciate the value of this often overlooked plant characteristic, Bletilla striata is a must. As the leaves emerge each spring, they remind me of a crop of newly germinating palm seedling, although others have compared them to a dwarf bamboo. There are forms with variegated leaves and with leaves which have a striped margin. This last characteristic is perhaps not uncommon; plants in my garden are certainly displaying it.

The flowers nod loosely from wiry stems and are normally a rich rosy-purple. There is a white form in cultivation which resides under the rather cumbersome name of Bletilla striata var. japonica forma gebina. Having purchased what I thought was this plant several years ago, I was surprised to see that the unfolding flowers were more pink than white (although this image doesn’t show that too clearly). I would be interested to know if others have shared this experience. One or two nurseries are now offering a yellow-flowered variety.

Propagation is pretty straightforward, division being the best method. I have successfully done this from the time the plants first become dormant in the autumn, through to the time when the first shoots are just nosing their way through the surface of the soil in spring.

Of all the different types of fragrance emitted by flowering plants, the scent of honey must rank as one of the more unusual. In gardens, it is probably most often encountered in the flowers of the shrubby spurge Euphorbia mellifera and in those of its close cousin, E. stygiana. Given that E. stygiana is native to the Azores, where the climate is described as mild/temperate, this evergreen shrub is surprisingly hardy here in the UK. I grow mine in a fairly cold garden on a north west facing slope on clay soil. On mornings after a hard frost it looks pretty forlorn, the foliage drooping and the whole plant apparently in a state close to death. However, once the temperature rises the foliage perks up again, and so far the plant has suffered no permanent damage. It is worth noting that this is exactly the same thing that happens to the hellebores in my garden - plants with a much hardier reputation.

As referred to earlier, the flowers of E. stygiana give off the delicious aroma of honey. This can be quite strong, detectable at some distance from the plant. I thought it might be interesting to examine what type of insect pollinators this scent might attract, so over the course of a few days I spent some time observing the plant’s visitors. Taking a close look at the flowers of Euphorbia stygiana, it is clear that there are no long tubes down which an insect blessed with a sizable proboscis might search for nectar. This could explain why I saw no butterflies or moths visit the plant (night time observations may reveal otherwise, at least as far as the moths are concerned). So, does the scent fail to register with our native lepidopterans or are they simply not being presented with the type of flower shape that normally attracts them? Perhaps both factors contribute to their absence. The only insects I did see visiting the euphorbia were flies and ants, both of which can be seen in the image on the right.

The shrub itself grows much wider than high. Mine has attained a height of about 1.5m but is comfortably twice this across. It can be propagated from cuttings which, like many of the spurges, take two or three months to root, or more easily from seed. The aforementioned Euphorbia mellifera has the tendency to produce its own offspring around the garden. I have not noticed this trait in E. stygiana yet.

The tree peonies, of which Paeonia delavayi is one, make up a group of extremely hardy shrubs (definitely not trees) which are amongst the easiest of garden plants to cultivate. They will tolerate most soils, flower reliably year after year and regenerate from hard pruning. Some, like P. delavayi and P. lutea, are obliging enough to sow themselves quite freely, with seedlings appearing beneath the parent plant in spring. This means that propagation is not an issue. (Of course, things are not always that simple; some tree peonies require a lot more effort if you are to propagate them successfully.)

Paeonia delavayi is a deciduous shrub which is particularly tolerant of alkaline soils. It grows to a height of around 2m with upright shoots, although the younger shoots have a tendency to arch over when in flower. The image on the right shows a fairly young plant - only in its fifth year since germination - but already in its second flowering season. The flowers are blood red, about 10cm across and to some people slightly fragrant; but as with the majority of plants, they are relatively fleeting. The foliage, on the other hand, is present throughout the growing season and the large, much divided leaves with pinkish-red stalks remain attractive until autumn. At this point they become withered and brown and, being reluctant to fall, may need a gentle helping hand on their way to the compost bin.

It is at this time that the seed pods split to reveal their shiny black seeds - the eventual source of the seedlings mentioned earlier. These can be carefully lifted from the garden and potted into 9cm pots. Keep the plants growing by potting on as necessary before planting out into their final position the following year.