- Try and do your dividing on an overcast day or at least not in during the hottest part of the day.
- Don't leave the exposed root ball sitting about any longer than necessary. Hot sun and breezes will quickly dry the roots.
- Keep them well watered until new growth appears.
- Provide some shade if they appear to be wilting during the afternoon. A floating row cover will protect them from the hot sun.
Perennial plant division is intimidating when you first think about tearing apart your precious plants, but the more you do it, the better you will get at it and the better your perennial plants will grow.