I live in the southern Arizona desert. It is very dry (we are currently in a drought) and I water them every day
Can I thin and transplant my canna lilies mid-summer?
It is not ever a good idea to transplant and or thin out any type of outside plants in mid summer. My suggestion is to wait until fall, when it cools down some. The heat and dryness will kill your plants.
Reply:You sure can. Water them like crazy for the rest of the summer--gallons and gallons and gallons... or leave them until September to save money.
Reply:You can but it is not the best time, they really don't have time before winter to fully recover from the transplant shock before winter sets in.
Best to do this late fall thur late winter