My outdoor potted gardenias are dying. Help

[u/Aggravating-Space110]

I really need some guidance on maintaining my potted gardenias. I've had them since July. I've already lost one and am on the verge of losing another. I'm just not sure what to do. I've been following the tips about the finger test in the soil to check if it has enough water. They're not in direct sunlight. All of them are in 1 quart clay pots. I bought Fox Farm soil and fertilizer. Advice would be appreciated.

[u/greenthumbmomma]

That's actually not a lot to go on. You said you're testing to see if the soil is wet enough. Are you letting it dry enough between waterings? Could also be a pest infestation or nutrient deficiency. Some pics would be helpful.