My basil plant I recently bought and planted has been going bad. The older leaves turn yellow and fall off. I suspected root rot but now I am not so sure. I was wondering if it needs to be fertilised?
Yellow leaves are usually a sign of under or over watering and not necessarily an issue of adding more fertilizer.
Also, it's not all that unusual for the bottom leaves of a leafy plant to turn yellow since the top growth typically starts to shade out the bottom growth and deprive it of sunlight.