Bay trees

I find bay cuttings quite difficult to root successfully, so you've done really well so far!

I think they've been busy growing a good root system first before they can start growing above ground, and they will grow faster this year.

 If you can't wait to block out the road then you could replace them, but it seems a shame now that you've come so far - it will be great to look back when they're a lovely thick hedge and remember taking the cuttings.  

Take a photo of them this year and another next year from exactly the same spot, then you'll see how much they've grown!  But bless 'em, they really do need time to grow some good roots before they can thrust those branches up into the sky - after all, they didn't have any roots at all when they started, did they?

I grew some on from suckers from my big bush. They were very slow for a couple of years but eventually got established. I think they're just slow starters

Seems to be the case with Bays, the first year they seem to get established then grow well after that. 

You're lucky to have bay trees, I keep loosing mine during the winter and now have to keep them in a pot and carry them into the greenhouse for protection when the weather gets cold.

I would not  encourage it to grow faster than it needs or it will go lanky and fail,your lucky to get this far they are not easy to grow.I have grown them before but you have to be patient

Bay treers are very slow growers and they do not like growing in rich friable soil. Their favourite soil seems to be heavy clay although I have seen them growing on the Cornish cliffs, struggling it is true, very small and stumpy. The best I have ever seen were huge ones in Prospect Park  in Reading. No attention given to them in many years, on hard heavy sticky Thames Valley clay.

I am growing a sucker from my sister's tree but it is moving very very slowly.

Blossom, maybe it's the roots that are suffering if they're in pots. My big bay started life in the ground in S. Cambs. Now doing well further north in the ground again

It may be the excessive water and more recently the freezing conditions have killed them. Mine has been in a cold frame so has had a little bit of protection, despite me not putting the top of the cold frame on.

Give them a chance - you may find they sprout fresh leaves in the spring.