150 watt: take the lamp 20-25 cm above the plant.
A Sativa takes 11-13 weeks.
I had once
-silver haze
-strawberry haze
-hawaiian snow
-neville's haze and they go all for 18 weeks flowering.
The beginning was all good then in week 10 the had fluffy (means, softy tops) not swelling, no trichomes....
what to do:
take your lamp down, they are now in week 9.
make 10 weeks FULL with nudes.... please look what they do.
Further the 2 last week flusch theme verry good and the last week give theme nothing.....the last week nothing and the last 3-4 day's take the light away so the stay in completely darkness before cut these.
trying to do this also:
on the bodom you see the steal of the plants, take a toothpicker and push that into the steal (don't know the good word)
you give theme so manny stress that the plants will produce thc.
other you can break a top just between finger and middle finger and ....break theme, break over and it's hanging there. the plant do recover her and do her best to be alive so you can make many trichomes. believe me, have 8 years exp.
but the first thing about the toothpickers will work realy good, i do that every thime normely in week 7 (last week of food)
(look thise picture, you will see the toothpicker on the bodem)