Question
my phlox have been in for around 8 or 9 years they flowered this year then on one side of the bed they starting turning brown now the whole bed is brown they look dead.  
should i dig them up and replant?

Answer
Hi Theresa

Phlox are hardy alpine plants and as with most alpine, they look their best for 4 to 5 years and after that they decline. It sounds like that yours have died so they won't come back.

My Phlox Subulata 'Red Wings' is looking the same and has been declining for about two years and it is about 4 or five years old. I need to replace it and it has not flowered too well this but the last time it had lots of blooms was last year after a bad winter that made it look brown but by spring it had lots of lush growth and lots of flowers. This year it looks sorry for itself.

The best thing to do is dig them up and replace them and renew every 4 to 5 years.

Thankyou for your question.

Take care.

Jonathan.