Rosebay Willowherb - Tall Flowers at the Back Please

You've probably seen these growing along the roadside in the country. Rosebay Willowherb also known as Great Willow Herb and Fireweed is a perennial weed (or if you prefer, wild flower) which can grow up to 8 feet tall.  It gets the name Fireweed because it is one of the first plants to colonise burnt areas of forest and was a common sight in bomb craters after WWII (the plant was also called bombweed).
These plants propagate naturally by seed, but also spread by sending out underground stems (which according to Wikipedia are called "stolons" . Runners are overground stems which root, as in the case of creeping buttercup, briars and strawberries).

Image courtesy Eileen Henderson CC SA 2.0 via Wikimedia Commons

I've had a patch of these for a few years growing in against a hedge. The seeds probably arrived with the wind. New plants have appeared around the originals, so I dug them up last year and separated them from their parents. They should look good at the back of the herbaceous border, towering above what's left of the delphiniums.....

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