Pink or white Silene
Campions are a like a variety of habitats, and grow to a variety of heights to 90cm. The flowers are generally about 2cm across in shades of pink or white depending on species, and you can see that the white ones often have a pink tinge on the calyx tube, which is in various states of inflation (hence the name “bladder”).
Campions on the coast
Two campions I have spotted within metres of the beach are Sea campion – Silene uniflora / maritima at West Beach Whitstable Kent and Bladder campion – Silene vulgaris on Seaford Head Sussex.
Red campion inland
I did spot red campion – Silene dioica recently, on the edge of woods in Kent. The second picture possibly shows better the hairy nature of the stems and red calyx, and the white eye.
Campion seed heads
You can see two more white campions along a hedge in a field in Seaford.
Blog posts mentioning Campion – Silene are tagged Campion or Silene
https://photographingwildflowers.co.uk/tag/campion/
https://photographingwildflowers.co.uk/tag/silene/