Question, how tall a plant will get in flowering?

I've seen people say they will grow 1.5-2 times what they are before they go into veg for indica, and 2-3 times there highth for sativia is this true?

I'm new and don't know much and I would really appreciate the advice.

It all depends on the strain and if you top/fim them. But I would say that could be a decent generalization to use.

I've been reading that for a few years now on here, and to some degre it's true. Mine have never doubled in size though, maybe because I'm a soil grower using CFL's and not MH or HID lighting. The height will absolutely increase though, Mine just never actually double or even come close. I will veg for typically 8-10 weeks as I don't like "forcing" flowering before the plant is mature. They are usually about 3-3 1/2 feet tall before they start showing sex and after flowering they may end up at about 4 1/2 feet, but again, have never come close to doubling.

Strain... lighting.... feeding/watering schedule.......pot size....time vegged.... etc all effect the overall plant size.
Some strains under certain condition hardly stretch at all.
Some strains can trebble in size from start to finish of flowering.

The two strains I'm most interested in are White Widow and Sour desil.

What would the estimated heights of both those strains be if they were topped and grown to 18 inches and put under a 1000 watt light?

Thanks for the help everyone.

TOO many variables ....temp ......humidity...pots size.
if you look at the breeders catalogue they all give an indication of outdoor/indoor size and for those sites that don't..... go here and their catalogue tells hieghts.
http://wig.bz/6w

I heard that most plants can grow as high as they'd like,
I know there are some additives that can be used to reduce the vertical growth and concentrate on the lateral growth.

Mine always triple in flower, except for a pure indica strain that doubled. Using a 600 watt HPS. Had about 4 grows. I always wind up tying them down because I have a height limit.