I think they say 2-4x in size based on strain. I grow a very low strain, heavily trained and tied so I'm closer to 2x. But they do stretch and fill out a significant amount. I get like 5-10% from stretch alone in the first couple days.
Ok when they say 2-4times, that full of crap unless u are growing one stalk I am on day 33 of floweringView attachment 2044267View attachment 2044268and except for the colas adding several inches the plant is still the same size. Now the buds will begin to get denser.
This is a month ago when I started flower. The plant is denser and a tad bit taller so it grow all around but I would say like by 30%-50% not 2-4 times. Peace.