With its narrow stems and tight clusters of purple flowers Verbena bonariensis has been a firm favourite of designers in recent years.
Used at the front of a border it forms a semi-transparent veil without obstructing the view of the planting behind.
The only drawback I’ve found is that the tall stems can begin to droop and look untidy particularly later on in the season.
But now there is a new more compact selection available called “Lollipop” which only reaches half the height and is more practical for use in the narrow borders of most town gardens.
The flowers which last from June to September are irresistible to butterflies and the plants will liberally self-seed.