Posted: 21/07/2014 at 10:52
Removing the weeds might help. Take them out of those pots, prune the bottom inch of roots off and put new compost in the bottom. Scrape off the top two inches of soil from the top (also removing the weeds) and replace with new compost. Buy a feed for ericaceous plants, add to rain water and water them weekly with this during the growing season (more often with just rain water if the weather is hot). I top my pots off with large gravel.