I had a company fertilize many of my cedars in my yard mostly larger ones. The company also fertilized 2 small cedars located in front of my home which I notice turned brownish/yellow after a couple of weeks.
I’m trying to figure out if there dying or burnt and if there’s a way to save/revive them back to there original green look.
Cedars can sometimes be tricky plants to take care of with over/under watering, light conditions, soil make up, transplant stress or exposure to winter salt particles/spray sometimes leading to browning of the leaves. You do not say how old the affected cedars are or what soil and light condition prevail, so it is difficult to pinpoint the exact cause of the browning. Road salt from a walkway or cars parked close by in a driveway may also be adding to the problem.
Commercial fertilizers too can have a detrimental impact as it can burn tender roots and inhibit the plants ability to take up nutrients & moisture from the soil. I would recommend contacting the company who did the fertilizing to alert them to a possible problem as they may have some advice or solutions for you.
I’m attaching a link, see below, to a previous question that was posed to the Toronto Master Gardeners regarding feeding Cedars, which you may find helpful.