I have 4 maxi-rhododendrons planted in soil which is contaminated with juglone from several nearby trees (not black walnut, but I'm told these trees produce juglone, too). They are slowly dying despite my best efforts at amending the soil around them and watering them well. Any suggestions on how to save my rhododendrons? I cannot move them.
Can Rhododendrons survive juglone?
Not for a long time and no if you do not take proactive measures. I suggest that you girdle the tree roots and then dig a 1' trench around the rhododendron bed. Remove any roots going into or out of the rhododendron bed. When planting new shrubs on the rhododendron bed, do not mix the soil with ammenments but rather, dig & remove the soil completely. Replace it with new soil.
Some people have had some success with hydrangeas (the macrophyllas, serratas and the Anomola subsp. Petiolaris Climber) in similar circumstances.
Yes, my hydrangeas don't seem to be effected. Thank you.