Answer: Your rhododendrons should be fine as long as your selections are rated hardy for your local area. Rhododendrons should be watered -- if needed to supplement rain-- enough to keep the soil moist (not sopping wet -- check it with your fingers) until it freezes for the season.
A layer of several inches of organic mulch such as shredded bark over the root zone (do not allow it to touch the stem) is also a good idea.
If they are in a windy location, a wind break such as a burlap fence or section of snow fence or picket fence can help keep them from drying out unduly.
Some gardeners will also apply and reapply an antidessicant spray being sure to read and follow all the label instructions. Good luck with your rhododendrons!
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