I don't know about beer, I would suggest honey though. I have been using it on mine due to them being neglected for several months while we were moving. I use it with my regular fertilizer and then mix the water very well. I read somewhere to use 1 tsp. to 3 liters of water. I am told it has natural healing properties and the sugars will make your plants perk up. I use it in heavier mixtures for my Vanda types and heavy feeders.