Planted it late last year in a brand new garden (clay soil). Was doing really well but never flowered. Cut it back over winter, and until 4 wks ago it had come back brilliantly - growing quickly with loads of buds. Unfortunately, we went away during the hottest week of the year so far, & when we came back it had all wilted & turned brown . I've cut it back again & watered it daily (for 2 wks), but no sign of anything back yet. The roots are under gravel & another plant, which is what i believe you're meant to do (& also means it'll be bloody difficult to pull up & start again).
Any ideas?? Should i just give up, or can they come back??
TIA, am a complete novice at this (but v keen)!