Both will need to be monitored so that they don't dry out. Containers that sit in the sun can be made cooler by lining the interiors with Styrofoam insulation. Soils for Containers Never use ordinary yard soil in a container. It's not only too heavy, but it also may bring along the weeds and nematodes you're trying to escape. Choose a high quality soilless mix specifically labeled for use in containers such as Peters, Miracle Grow, Metro Mix or Fafard.
Some companies make different mixes for different kinds of plants.
Most mixes are pH balanced and contain enough nourishment to get plants started. Many gardeners like to mix in compost, such as mushroom. This is a good practice because the compost will gradually feed the plants as they are watered. Constant watering washes out nutrients, which must be replaced. Watering Containers Instead of putting a matching saucer under an outdoor container, turn the saucer upside down to lift the pot off the ground and help drainage.