Where we live too need to have permission from the council to so much as cut a twig from your own trees (or anyone elses) if they are over 2m tall. however, you can plant as many and as large a tree in your garden as you like an there's nothing can be done about it.
The neighbour next door, who has fallen out with us over another unrelated matter, has planted trees all along the boundary of our gardens. The gardens are long and thin and north facing, therefore, because she is to our left they shade our garden from the late afternoon and evening sun- which is the only time of day it really used to get the sun. In particular she planted a cherry tree directly opposite our previously sunny seating area, which in the four years since she planted it, it has grown to about 30 foot tall already- it was quite a mature specimen when she bought it but it's growing like a weed! There's nothing we can do because they are deciduous so don't class as a hedge as there are some gaps. She won't speak to us about the trees.
It shouldn't be allowed in my opinion without planning.