leaves turning yellow

Plant is all natural planted in the ground.. started about middle of may plant is about 3 1/2 feet tall.. i got no bottom leaves pretty much all leaves left are on top. i have been picking off the yellow leaves after they r getting really yellow and idk why this is happening but it seems to be moving upwards in the plant im afarid that the buds might die is there anything i can do to save them right now?? they are aready starting to bud the hairs are white and its smelling really good..please help its my first grow

That sounds like a classic nitrogen deficiency to me. Kinda like what you get when you flush before harvest but in your case, way too soon. You can pick up a NPK test kit for less than $10 to see for sure. If you lose too many leaves though you won't recover so time is of the essence here.

i have never used any nutruents yet.. the bud is in 4th week of flowering u think i should add sum cuz the only thing i tried was coffee grounds

yes bos get some fert on it and quick. Some good grow nutes would be best, but anything with a high Nitrogen ratio is fine. You can even use your own urine at a ratio of 1:10 water.