Complex sentence: Several specimens were acquired for assessment by "Butterfly Conservation" in Hampshire, where it has grown rather untidily at most sites, moreover the stem initially proved weak and unable to support its burgeoning crown, necessitating staking for up to five years.
Split into simpler sentences: Several specimens were acquired for assessment by "Butterfly Conservation" in Hampshire. It has grown rather untidily at most sites, moreover the stem initially proved weak and unable to support its burgeoning crown, necessitating staking for up to five years.