Question
We recently had a local garden center plant 57 arborvitae trees on our property and we're having problems in that they are turning brown at the bottom and middle. We've received conflicting information about how much mulch should have been placed around the bottom of the tree and how much watering should be done.  According to what we've been told there should not be any mulch around the bark of the tree and no more than an inch or two around the tree.  The trees were planted with a good amount of mulch up to the bark/trunk of the tree.  Also what is the right amount of watering that should be done at this point?  We've been told every 5 to 7 days, depending on the amounto of rain we've had or about 2 " per week.  Please help. We don't want to lose all these trees.  Thank you.  

Answer
Nancy,

Mulch should be kept away from the trunks of any tree. Crown rot can occur if the mulch is piled around their bases. Mulch should be 2 to 3 inches in thickness to protect the roots and smother out any weeds.

I would recommend watering only when needed. If there is no rain in the forcast for 2 days, then water the plants for 15 to 20 minutes using a soaker hose.

i would further recommend applying a granular organic fertilizer to the root zones of the plants to stimulate growth and help ease transplant shock.

Good luck,
Ed Gulliksen