Answer: Something you may not have considered is radiated heat from the sunshine. If the planter is getting direct sun it can act like an oven and actually bake the roots of your plants. If there is a way to shade the planter, or if you can somehow insulate the sunny side, I think you'll have better success with your plants. If you remove some of the soil you can work a 3/4 inch thick slab of syrofoam insulation against the sunny side of the planter. You can purchase a 6' by 4' by 3/4 inch sheet of insulation from your garden center. They are manufactured for wall insulation but will work for your situation. Slide a piece between the soil and the side of your planter. Then work some compost or other organic matter into the soil if you are using garden soil instead of potting soil in the planter. The organic matter will improve drainage and yet hold just the right amount of water. Be sure to choose heat loving, drought tolerant plants for your planter and I think you'll have better success with your planter. Best wishes with your project!
Q&A Library Searching Tips