water plants when they need water.. insert finger and find out ...

see link for a multitude of great info ...

https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub

looks like someone was hoicking these things around by the top of the plant .. grower.. wholesaler.. shipper.. seller .. you??? .. talk to your seller ...

that pattern of damage.. does not look to me.. like a root problem .... an overall decline that would indicate an overall problem ...

but do read the link about amending soil.. and think about all the extra money you slathered on your seller ... and do get some mulch down ...

did you happen to perk your soil to find out its drainage capacity???

ken

As the roots go, so goes the top. Monitor moisture situation inside original soil balls until plenty of rooting out into surrounding soil has taken place. Before then the amount of dampness in the soil outside of the balls will be somewhat irrelevant, unless it becomes excessive*. And unless it rains buckets on a sufficiently frequent basis precipitation will not serve as a substitute for watering. 1 inch per week is the minimum amount of rainfall to meet the needs of established plantings, that do not consist of particularly drought adapted kinds.

If you've kept all of their roots consistently moist this whole time and they go bad later anyway then they were dug without enough total room volume to remain viable or they were allowed to dry out too much at some point between being removed from the growing area at the production facility and being planted at your place.

*Sitting in water can also kill nursery stock but arborvitaes going brown from the tip down would ordinarily be expected to be due to the top not getting enough of it.

Hi Hil, Your jumping the gun a little bit. Its gonna take quite a while for a new install using plant material of that size to get themselves sorted out and on their on roots. Some browning can happen from many reasons. They need some time. Right now the install is complete, so you can't change anything in that regards. I'd advise you to not try and fertilize them happy...now its a long waiting game...

Al