" What are the signs of a successful transplant"?

Time. Correct care before and after planting in the mix also.

Why did you buy a dry root ball conifer with needles drooping in the first place? Did you notice if the root ball was broken? If so there is a good chance it will succumb to HD employees loving care for it as it sat on their hot black top lot.

Dave

has it already budded out???

such would be a good sign of some life ...

interior needle drop is normal..no conifer holds its needles forever ... and it is sped up by the digging/shipping and planting processes ...

at least you have a warranty ... keep the recpt handy ...

in the future.. understand that a transplant.. about half that size... has much reduced stress... and is easier to deal with all around ... including getting re-established faster ...

pix might help ...

how did you plant it ... if you want a critique of such ...

ken