I may have to try this ***Homemade MIRACLE GROW*** : 1 gallon of water, 1 tbsp epsom salt, 1 tsp baking soda, tsp of Household ammonia. Mix all ingredients together and use once a month on your plants.
Make cement cloth planters. Approximately a water/cement ratio. Add drainage holes in the planter before it completely hardens to prevent cracking. You may also want to apply a couple coats of cement sealer after the planter is dry.