This is one plant that you need to invest in ericacious soil (acidic). If you are unsure of the soil Ph then perhaps checking what your neighbours are growing would help. They do like to be in the earth itself, so adding lots of acidic soil and then keep adding ericiuous feed will help. The first sign of the glossy leaves looking yellow means that you need to add more of the ericacious feed.

If you intend to plant in the garden, then a simple soil test will tell if the soil is acidic. If it isn't, I would suggest that you plant in a large pot with John Innes Ericasious Compost. Best planted in a west-facing position in partial shade.

Thanks for all your tips I thought it might be acid soil