While we update our systems with the new hardiness ratings you may still see old
hardiness ratings in your search results. These are denoted as 'Old'.
- H1 - Requires heated glass
- H2 - Requires unheated glass
- H3 - Hardy outside in some regions of the UK
- H4 - Hardy throughout the UK
- H1 + H3 - Requires heated glass but may be grown outside in summer
For full details of the hardiness ratings see