gardeningblog

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.