Beginner Gardening: My spearmint is not healthy., 0 by Kairos

Kairos wrote:
I don't really know much about gardening. That said I've been doing a lot of research as to why my spearmint plants leaves are curling downwards and turning brown at the tips. I don't know if it's root rot, Anthracnose, too much/little light, or heat. I live in Miami a six story apartment that faces north. Where the plant is only gets direct sunlight during the evening. The entire apartment is kept air conditioned at about 70 degrees. Any suggestions?