Stonerdanswered grow question 4 years ago That is not normal!!! Those are signs of deficiencies!! Potassium (K) and Nitrogen (N).
If you "flushed" your plants nearing harvest then that's probably the reason and you really have no reason to do it! and I'll explain:
Flushing your medium slowly reduces the salinity and nutrient value of it, that means less nutrients for your plant to maintain green and healthy foliage. Now the leaves are the most important part of the plant especially during flowering since they supply your plant with energy (performing photosynthesis) through sugars and proteins produced in them, and foliar growth comes to a halt after a couple weeks into flowering. The nutrients/chemicals/salts and minerals you believe get stored in your buds are actually stored mainly in the leaves! Those nutrients maintain and regulate growth hormones and transpiration through the plant and contribute to foliar growth *through photosynthesis and protein production (Nitrogen is mainly responsible for that)*
*The only thing that may affect your buds' taste and smell is a Nitrogen toxicity which causes increased chlorophyll production (hence the darker green color) and gives your buds a more "Grassy" taste and smell.
*Plant should have healthy lush green foliage throughout the whole grow for best results!! (and no "chemical" taste to your bud...)
Hope this helps! Good luck and happy growing :)