Will my plants double in height?

Hey guys I have three cannatonic girls almost at the end of their veg cycle. I’m in Australia so thinking they will go into flower the next week or so.
They are about 3 1/2 feet tall, my question is will they double in height or will they just fill out more in size when they flower?
I want to be proactive on this and tie them down if they will keep growing in height, as it could become a security risk with the neighbours.
Thanks guys

It is prob going to be around 5'to 6', 60inches to 72" tall.

Yea they go crazy in the stretch...specially since you are outside.

If you see them shooting up more than you’d like just bend the tops over. Or put a trellis above them now, and train them to grow wider rather than taller.

Thanks guys I appreciate the quick replies and advice. Here are some photos any advice on how to tie them down the best? Thanks again

Wire pegs work for me

Hey greenhobbiest I'm also growing in Australia your plants are looking awesome by the way. If your worried about height just keep bending and tying with soft plant ties. Bunnings sell it cheap as.

PhillyAlex said:

Hey greenhobbiest I'm also growing in Australia your plants are looking awesome by the way. If your worried about height just keep bending and tying with soft plant ties. Bunnings sell it cheap as. View attachment 4468931

Click to expand...

Hey mate cheers. Your plants look great, what are you growing? Yea I ended up tying them down which has helped heaps. When do they normally start flowering in Vic?

Greenhobbiest said:

Hey mate cheers. Your plants look great, what are you growing? Yea I ended up tying them down which has helped heaps. When do they normally start flowering in Vic?

Click to expand...

Hey dude only new to growing they were all just a few seeds that me and my mate had saved overtime luckily they were all females beginners luck. But I’m not sure on flowering times in VIC nor NSW but I reckon in the next couple of weeks we’ll both start to see the change. Good luck on your grow dude