Friday, 11 October 2013

Spiraea thunbergii

Spiraea thunbergii
I get the impression that Spiraea is one of those groups, like Hypericum, that most keen gardeners tend to scoot past, and generally speaking I'd do likewise, but I've come to learn that almost every group has something choice to offer and it can be fun locating it.

Spiraea thunbergii is one such gem - hardly an obscurity (it has an AGM after all) but I hardly ever see it in gardens or nurseries. It is an exquisite shrub combining sprays of pure white flowers with the lightest and freshest of pale green leaves, all in a loose billowing (but not overly large) arching shrub up to about 4ft tall and across. Mine flowers surprisingly early in the year (March) and goes on into May. After that the foliage and form make a very pleasant contrast to darker heavier plants, and are never even slightly ugly.
Can be pruned quite hard after flowering if neccessary and I imagine it would make a good informal hedge.
Very easy to please on any soil in sun. Absolutely spiffing in every way.
1L pots ~ £7



More Autumn flowering labiates

Following on from my listings of Colquhounia, Elscholzia, Rostrinucula and Keiskea, here are a few more to look at. All have a pleasantly informal easy-going look that is perfectly in keeping with the season. They combine as well with the sunflower types (Helenium, Rudbeckia etc) as they do with the autumn flowering woodlanders such as Tricyrtis. All are ideal for covering up after the Trilliums and Erythroniums are done.

Rabdosia longituba
Isodon longitubus (aka Rabdosia longituba or Plectranthus longitubus)
Despite the indecision over the name, one of the absolute best late flowering perennials, with shoals of clear violet flowers over a long period from late summer and well into autumn.
Rabdosia longituba
The flowers really glow in the low autumn light like tiny violet blue gas flames. The camera never does it justice. Any soil in sun or semi shade. Easy but may not emerge until May or June.
sold out for now - more later in the summer


Plectranthus excisus
Plectranthus excisus
Closely related to the above, this one produces a profusion of violet flowers too, but in long slanting racemes.
Plectranthus excisus
The foliage is also unusual in shape and takes on pleasant tints as the season progresses.
May be late to appear in summer. Very few this year, but more next.
sold out for now - more later in the summer

Chelonopsis moschata
Chelonopsis moschatus
Quite different - this one has tubular pink flowers more like a Penstemon (some of which used to be classified as Chelone - hence the name) and foliage that reminds me a bit of a Hydrangea. This is a rhizomatous perennial, spreading steadily but not in a bad way. Usually grown as a woodlander (where it is admirable) but adaptable, and flowering over a long period.
sold out for now - more later in the summer

Leucosceptrum stellipilum formosanum
Leucosceptrum stellipilum formosanum
Mauve pink bottle-brushes and large (to 6ins) fresh pale green foliage. A lush leafy herbaceous perennial related to Elscholtzia, Agastache and Rostrinucula, and with the same late flowering season - well into November if the weather allows.
Leucosceptrum stellipilum formosanum
Possibly best in sheltered woodland to avoid hot sun and early frosts which can damage the display. Otherwise easy and adaptable.
2L pots ~ £6



Salvia reptans

Salvia reptans
Very different – this is a slender willowy American, very late f;lowering species with very narrow, almost grassy green leaves, giving a very light fresh effect in the garden among grasses or grey leaved shrubs. The flowers are exquisite – small but of intense cobalt blue on fine stems above the foliage and produced from September until the frosts. For open well-drained sunny sites.
Salvia reptans
Two things: like many bushy Salvias, the stems are quite brittle, and the flowering, being so late can be spoilt by harsh weather, so although quite cold hardy, all in all best given some shelter.

Ps. not to be confused with S.repens which is a low growing S. African species with short spikes of mauvish flowers. I think both reptans and repens mean creeping (as in reptile) but this one, so far at least, does no such thing. Strange...
2L pots ~ £7