2 plants im currently growing had a lack of trichomes well into flower,they only started producing more of them the past week or two(I'm at week 13)
Not sure if it was the nutrient change,as I changed from using Dutch science nutrients(organic) to general hydroponics flora trio about a week or two ago.
There might be some strains out there that don't really produce many trichomes until they near the end of their life?? I have no clue
Hope they start frosting up soon!!