This is a pic of one of a few leaves that are starting to do this about 2 weeks into flowering. The ph is 6.5 and no ferts so far. 600 watt MH lights and girls are about 2feet tall. Jock Horror. Temp is 80 and humidity is 40%. Will be adding earth juice bloom soon. Any suggestions. It is more on the top leaves than the bottom. Thanks for any help!
It looks exactly like a Phosphorus deficiency, but that should start on older leaves. Phosphorus is vital to bud growth, so start feeding now.
Once a week is probably fine. Remember as your plant finishes flowering to stop feeding a week or two before harvest.