Pelleted garden Gypsum will help wash the salt out of the soil. Water it in with a couple of inches of water and continue to irrigate twice a week for a month. I would also consult with a certified arborist in your area as to whether you need further treatment or not. Do not fertilize as that will only add more salts to the soil. Good Luck Nancy.
Arborvitae Brown From Salt Water
Question From: M. Rettig - RHODE ISLAND
Q: We have a row of what used to be beautiful arborvitae, that is until Hurricane Sandy. The bottom parts of the trunks on 5 of them were covered in ocean water for 2 days. Once the water receded, we rinsed them thoroughly and did so over the next week. Now it's March and they are brown. There is some green underneath near the trunk, but it is not the vibrant green they used to be. Suggestions?