I have a 40 yr old plus Rhododendron and had large arm size branches crack during servere cold last winter, I sprayed the the crack which were almost all the way broken, made parallel slits with a knife in the bark, and buried the brances in top soil with bone meal and hollytone, hoping to get roots so as to transplant. The plant is heatly and leaves are green. When would be the best time to dig up and sever the branches from the mother plant and transplant? Albany NY area

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