yellow leaves!!! whats that mean

i have one female that is doing very nice except for the fact that most of the tips of its leaves are turning brown or yellow. my other female has the same issue and it also has some yellow leaves can some please tell me what may be causing this?

i have 2 ganja plants that are only about 3 inches tall ,they are diff kinda seed ,
they are kept out doors and given cana cocoa A n B about every 2 days but one off them has started to go yellow on the leaves what dose this mean

im new 2 all this grow stuff and im only doin it 4 some smoke in the summer i would gracefully accept any advice in what 2 do over the 4th commin months thanks

Dont have a clue what is cana cocoa A n B but if they growing in dirt I dont think they would need feeding every two days unless that is some real weak nutes of some type. Based on the limited info would have to say over nuted. Try watering with only water for a while and see what happens. Dont water till it drys up on top a half inch or so. Smart folks grow in Hempy Buckets. Dirt is the *hits. Looks to me like a person who wanted killer weed in the summer should grow it in the winter. Time you get a little 3" into the cure room it's gonna be very fortunant not to have died from frost bite. Now if you live near the equator I take all this back.

BW