Evergreen browning

Asked June 18, 2020, 10:24 AM EDT

Arborvitae and junipers planted last year and did great. Now I see spotty browning on arbs and dense on Juns. I feed with liquid acid fertilizer twice, two weeks apart end of May and early June. I kept well hydrated. Problem seems getting worse. What now?

Hennepin County Minnesota

3 Responses

It could be not enough water because they are not well established or too much water, test the soil before watering.

It could be from spider Mites
https://www.pennlive.com/gardening/2008/03/mites_on_arborvitae.html
it could be sunscald.
Trees usually do not need fertilizer, if they aren’t well established fertilizer will stimulate top growth rather than root growth.

What is sunscald and what can I do to treat/prevent?
I understand encouraging root growth is preferential. How best does one do that?
thank you.

Encourage root growth by keeping the shrubs watered until the ground freezes. Sunscald is caused by too much sun for tender plant tissue. Winter burn is a cause of browning on evergreens. They look the worst in in spring. So I think something else is wrong with you arborvitae.