|why are the leaves on my silver dollar eucalyptus turning brown and dry?|
Something is wrong in the roots. The most likely cause is drought injury. If the tree is less than a year in the ground its roots are still quite limited and can start to die back if the soil is too dry for them to supply the top with adequate moisture. Soggy soil can also kill roots leaving the tree lacking adequate water to the top. Over fertilizing can burn roots especially in a new tree with limited or confined roots. Dig down a few inches and feel the soil to get an idea whether it needs watering or not. Try to keep the soil moderately moist until the plant has a couple of seasons to get an extensive root system established.
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