Unhappy beech hedge

[cobain]

Hello all,

I planted a beech hedge back in February using bare rooted plants.....a few haven't grown but these are being replaced however what concerns me more is that some are starting to turn brown as in pictures below.

I'm sure that they are getting enough water as I have got a soaker hose running between them and the ground is damp when scraping off the first inch of soil, any ideas?