I have had my blueberry bush for 4 years it has always produced an abundance of berries and been a very healthy bush.
This year there was new growth, but the tips of the branches are turning brown and dying.
It has no leaves at all.
What can cause this? is there anything I can do?
It is very difficult to say whether this is a disease problem or a soil acidity issue. I suggest you take a sample of the bush, including healthy stems if you have them, along with dying and dead parts, to your local county extension office. Also try to dig about a cup of soil from around the bush for a soil sample, get only soil, exclude any grass, mulch, or other non-soil material may be on the surface. A soil sample will help rule out any fertility or soil acidity issues.