By Cacti66
London,
United Kingdom 
Does anyone know what type of cactus this is ? It has grown quite alot since i bought it 5 years ago but looks so similar to so many types of cacti ....i bought it in ikea without a lable and was my first cactus ....im wondering if it grows much taller of if its decreased growth is due to being pot bound ?
21 May, 2013
Answers
It looks like a type of Cleistocactus.
Try Cactiguide.com
21 May, 2013
Have a look underneath to see if any roots are showing through the drainage holes. If you repot it use cactus compost - you can buy quite small bags of it and its a lot more open and gritty than normal compost.
Remember to wrap folded newspaper round it or wear gloves!
21 May, 2013
Hywel thats exactly what i thought but which variety ...theyre so similar....winter one i think
22 May, 2013
It's almost impossible to tell the species of some cacti. Maybe if it flowers, you will be able to identify it.
22 May, 2013
I hope Hywel sees this h's the cactus expert
21 May, 2013