As its name suggests, Blackberry 'Thornless Evergreen' is a thornless variety, making berry picking a painless activity! White flowers appear on this hardy, evergreen blackberry bush each summer, followed by high yields of large berries in August. The fruits develop from green, through red to a plump, glossy black - and then it's time to pick your harvest! Height: 300cm (118). Spread: 300cm (118).