Cache is not at the posted coordinates.
Red Valerian, Centranthus ruber, is a drought tolerant perennial, often found in gardens, roadside verges and railway cuttings. It tolerates alkaline soils well, and so can also grow on old walls with lime mortar. Though native to the Mediterranean, it was brought to Britain in the 1600s and is now naturalised across the country, though it is more common in the south. The leaves are pale green and have a slightly waxy look, while the flower heads have large clusters of (usually) pink or red flowers. It has a long flowering season from May to October and is a good nectar source. The seeds are wind-borne, which means that it readily self-seeds and can become invasive.
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