I've been growing a potted gardenia since last year. It was hard at first (came pretty ill from the shop), but after we hit summer everything went great. Thing is, we started autumn now (living on southern emisphere, pretty cold now) and my gardenia has been doing not-so-good.
I noticed the leaves turning pale, but since we had a serious rain problem in our zone, I thought it was just overwatering and with some added iron it was gona be good.
I had to make a trip and left my plant in charge of my parents for some days, and wen I came back I found this

Some leaves had fallen already. and the ones that are still green are slowly geting paler
Could this be cold damage? Lacking any nutrient?
Whatever advice you could give I'd appreciate it