yellow leaves;
1) too much water?
2) not enough nitrogen
3) iron or other micro nutrient deficiency

Yellowing leaves from the bottom up is normal for indoor grow as the plants use up the nitrogen in the medium. Growers don't replenish toward the final bloom phase as the green leaves do not help with the bud growth and taste. The same could be said for outdoors in a container. Usually in the earth they plants don't yellow until very late, if the do at all.
Shovelhandle Reviewed by Shovelhandle on . First Outside Grow (midwest) Hey guys just started my first grow bout 3 months ago and now started running in to a problem so I'm here ;). They were just beans from a bag of some dank nug but my plants were looking great the whole time till bout 2 weeks ago they started turning yellow (the leaves) and now more and more are turning yellow everyday... just need a few tips if anyone has ideas please let me know. Rating: 5