Q.Transplanting astilbe after dividing
After dividing my astilbe (Montgomery) I would like to take it up to my daughter’s garden. This is about 4 hours away, but actually I probably would do the division somewhat before. My question is how should I care for the astilbe division after dividing and before replanting? Also how long can whatever you suggest enable me to wait before replanting? Should this be done early or late in the fall (September, October, or Thanksgiving)?

You can wrap it in wet newspaper, or paper towels until you get it to the location that it will be planted. I would suggest digging it up t the very last minute. The less time it spends stressed the better. As with most plants, I would recommend transplanting in early fall If you can catch it early enough, then this would be a good time to do it. Here is an article for more information: https://www.gardeningknowhow.com/ornamental/flowers/astilbe/how-to-transplant-astilbe.htm