20-25% ambers plenty dude.
Sure, it is enough,bro
But,everyone has his own grow technical,
For me ,I prefer 10-11 weeks harvest(8 weeks strain),
Some one use it for one month for flush , even if it reaches 85% ambers.
If you want your flowers to deliver an invigorating slightly euphoric high, then you should harvest when 15–20% of the trichomes have turned to an amber colour - this applies also to indicas - but if you're after a relaxing, narcotic effect that promotes sleep and helps you unwind, then wait until you have 80–100% of amber trichomes.
When indica hybrids are harvested shortly before they reach full ripeness - 15-20% of amber trichomes - the effect is relaxing and slightly invigorating. Once they're fully ripe, however, (30% of amber trichomes) they will deliver a more relaxing, slightly sedative effect that soothes the muscles and promotes sleep. Lastly, flowers that are harvested when 80-100% of the trichomes have turned amber induce a heavy, sedative, numbing effect.
Flowers that are harvested when 15-20% of the trichomes are amber induce a stimulating, clear, euphoric high, while plants harvested when amber trichomes account for 30% of the total have also a psychedelic edge. Lastly, flowers that are cut when 80-100% of the trichomes are amber deliver a heavy, narcotic effect that is highly psychedelic.(Sativa-dominant strain)