I bought this jasmine plant in a pot 4-5 months ago (in June, I believe) and it has been doing well, not too much growth, but quite a few flowers. It is still flowering. As it is getting colder, my plant is still outside (temperature over night never goes below 5c), sheltered from wind, with a lot of light. However, the leaves have started turning brown from the leaf vein outwards. By now, almost all leaves are brown, even though the plant still gives flowers. I have fertilised it once two months ago, and thought it might have been too much, so didn't fertilise again. I watered it evry other day during summer, now every week or so (depending on the amount of rainfall). My mother got one from the same nursery at the same time, her plant has not given any flowers but is very vibrant green and with a lot of new growth. She waters it every day.
 What am I doing wrong?