Wonderful black and blue!
Salvia guaranitica ‘Black and Blue’
Intense blue flowers from September to October
This is a vigorous herbaceous perennial that is 4ft high in my garden. It is robust and requires no staking. Years ago, a kind friend chopped out a small division for me in July. (Gardeners do not refuse pieces of plant, even if out of season) I now have many fine plants propagated by division in April/May.
Many perennial salvias are tender Mediterranean plants that must have superb drainage. Not this one, my best plants are in wet situations (but not quite boggy). Unusual too, it makes strong tubers, as large as dahlias. Although the plant is sometimes regarded as tender, my strong plants came through the two winters of 2010 without turning a hair. If this is not your own experience, the tubers can be lifted in November, potted and overwintered moist, in a cold greenhouse. Many of us found, to our cost, this was not the best strategy with tender plants in 2010. The cold was so intense and so prolonged that the roots of potted plants were deeply frozen. My tender plants such as agapanthus survived better in the ground.
I have just read that ‘Black and Blue’ can be propagated by cuttings - and seed too. Idiot me, of course most salvias are easy from cuttings! Too late now to try soft tip cuttings, yesterday I rushed out to take a dozen strong, ripened, basal shoots. I inserted them deeply in a single ‘long pot’ in my cold greenhouse. I have no idea whether they will grow!
Salvia guarantica in my gravel garden
Update November 1st 2014
Four of the aforementioned cuttings rooted. Two did not survive the winter in my unheated greenhouse. This is no surprise as an herbaceous plant that dies down to its winter dormancy soon after rooting has insufficient stored food reserves. The same principle applies to deciduous shrubs rooted late in the growing season when leaf-fall depletes reserves of carbohydrate and they fail to overwinter.
The two salvias that had survived from cutttings made only moderate growth and stayed in their pot for the whole of the next year. They remained in the greenhouse over the following winter before planting out.
It would seem to be an advantage to overwinter this salvia in a greenhouse in the north of England as they then flower earlier outside. The plant that had survived from my original cutting and got an early start from the greenhouse flowered from August until November.
In contrast my regular plants in the garden emerge to make new spring growth remarkably late. It's important not to forget they are there! I had almost given them up when they failed to appear until late July!
|This plant has been outside for several years and has now been in flower for two months|
|I could not resist taking a picture of this monster|