Rose Campion… Sounds like a good name for a romantic heroine. But no, it’s one of the common names of a plant, another tough, almost-weedy one that does well in my garden.
This common name, although charming, doesn’t really suit the white-flowered form (see the featured image at the top). Maybe that’s better represented by “Bridget-in-her-bravery,” although that’s quite a mouthful. I tend to call it Lychnis coronaria, or simply lychnis. That’s not quite right either, since (according to Wikipedia), the official Latin name is now Silene coronaria. Wikipedia also cites other common names: mullein-pink, Bloody William, and lamp-flower.
This is another relatively short-lived perennial that seeds heavily. Fully grown, it’s between one and three feet tall (30-100 cm). The growth habit is basal clumps of grey-green leaves with a sort of suede texture, similar to lambs’ ears (Stachys byzantina) but not as fuzzy. In spring they send up flowering stalks and bloom mainly in June and July. The flowers come in two main colours — bright magenta-red and pure, bright white. I’ve read there are pink forms and a white-with-pink-eye combination, but I’ve not seen either of those.
As with purple toadflax, to get the best from this plant, you have to deadhead. And unfortunately, deadheading rose campion means snipping off each flower individually, using scissors or small clippers. Each plant produces dozens of flowers, so weekly deadheading sessions are needed. That keeps them blooming into late summer and prevents copious seeding.
The spent flowers go through a limp stage and then quickly become knot-like seed pods. Left to their own devices, the pods ripen over several weeks. When mature, they open up at the top, like tiny urns poised to spill hundreds of seeds.
I generally deadhead flower-by-flower into August. By then, the plants are slowing down. They produce fewer buds and the bloom stalks start to look thin. At this stage it’s best to cut them down at the base, leaving the basal clump of leaves to finish out the season. In spots with a bit of moisture and/or shade, it’s possible to cut the stems by half in August for a fresh batch of late flowers in September. Because of the rather tedious deadheading requirement, I recommend keeping the number of plants relatively small (no more than 10) and situating them where you can get up close to trim off the flowers as they fade.
Here, rose campion looks fairly good all winter, although older plants may have quantities of dead leaves that resemble chamois leather. At my place there’s no shortage of rose campion, so I don’t hesitate to yank out any that are past their best. It copes well with the occasional snowfall and winter temperatures of -5 to -10 C (10-20 F).
Lychnis coronaria performs best in sunny spots, but is quite tolerant of light or partial shade. It doesn’t mind dry conditions, sandy soil, and competing tree roots. The white flowers are rather insistently bright, so a large number of plants in one spot can be too much of a good thing. The combination of white flowers and greyish foliage is elegant, especially with the sharp chartreuse, such as that of euphorbias. The magenta form looks best with other strong colours, rather than pale pastels. The two colour forms look fine planted together.
Rose campion is of no interest to deer and needs minimal watering. I suspect it prefers well-drained soils, although I’ve seen references to it growing well in clay soils. You can find them here (see the comments) along with more info about rose campion.