All our plants have a guideline temperature for how well they will tolerate winter cold.
Fully hardy perennials will withstand temperatures down to -15 °C (5°F) and often lower.
Hardy perennials are happy down to at least -5°C (23°F)
Half hardy perennials can withstand down to around 0°C (32°F)
And Tender perennials may be damaged by temperatures below 5°C (41°F)
Please remember that temperatures can vary significantly within quite a small area, and hardiness can be affected by soil, position and other factors.
If in doubt please give us a call.