Tough love suits red valerian
Some people detest red valerian because of its vigour and tendency to spread about. Others like its flowers and its tenacious ability to survive in the most testing of locations.
It is easy to assume that red valerian is a native plant because it appears so commonly on old walls and dry, stony roadsides. But it is native to the Mediterranean region of Southern Europe and North Africa, and, despite its southerly origins, it is quite hardy.
It survived in many areas in the two hard winters six years ago and, where it was killed, it came back from seeds shed before the freezing weather.
That said, it is generally seen in coastal areas, where it thrives. It is also seen a lot in towns where is colonises old stone walls. The plant does particularly well in the unpromising conditions of a stone wall because it likes very good drainage.
In its native habitat, it grows on dry, rocky, sunny slopes, usually in limestone areas.
The old stone walls were built with lime mortar, which is soft and allows roots to penetrate.
Red valerian makes a tough, woody rootstock from which arises the flowering stems each year. When it is growing in an old wall or in very dry ground, the plant's vigour is reduced and the plant grows hard and is drought resistant.
But if it is grown in good fertile soil with plenty of moisture, it can luxuriate in the favourable conditions and become very leafy and vigorous. It will still flower but not as well and the leafy flower stems tend to be relatively soft with the likelihood that they will fall over. Quite often, these over-fed clumps just split open in the middle and the stems flop around in a circle, and they look unsightly.
Although called red valerian, the flowers can be red, pink or white. It would seem that crosses between the different colours keep on repeating the colour variation. As young plants, the white ones can be told apart from pink or red types by their lack of red pigment in the leaves.
Flowering begins in late spring or early summer, depending on how well the plants over-wintered and although the first flush is the biggest, flowers are produced on new shoots and branches until early autumn.
If the first flower stems are cut away, late flowers can be induced.
I really don't want to kill my plant
Q: I won a lovely plant in our local children's hospital charity draw. Unfortunately, it didn't come with any instructions. I like flowers and plants, but I am not sure of its true identity. My friend thinks it a non-edible bay leaf plant and recommends putting the planter in water for 45 minutes at a go when necessary. The planter is extremely heavy and I'm just watering it about once a week so as not to over-do it. My friend also feels it would survive outside all year long as she has something similar in her garden. I don't want to kill off the lovely plant. Would you have any suggestions?
M Duggan, by email
A: It is a bay laurel and the leaves can be used for flavouring, unless recently sprayed. Bay is an outdoor plant and needs sunshine. It can be watered at the top to keep the compost just moist and Miracle-Gro liquid feed can be given every three weeks or so from April to September.
The pot may not be frost-proof and you may need to re-pot.
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