Answer: In deciding what to plant you need to analyze the growing conditions. Is it sunny or shady and at what time of day? Is it particularly windy? How much space do you have available? Is there a weight restriction? (Plants, moist soil and containers can be very heavy.) Keep in mind you will probably need to water once if not twice a day during the heat of summer. You will also need to fertilize regularly. Keep in mind also that the larger the container the better. Larger containers hold moisture longer and offer more insulation to the plants' roots in both summer and winter. If you have a windy site then you may need to provide a windbreak to prevent the plants from drying out too fast.
For a sunny space you might try sun loving plants such as ornamental grasses, crab apple trees, junipers, and perennials such as echinacea or rudbeckia. Or you could try annuals such as petunias, salvia, callibrachoa, and dusty miller. For a shady site you might try perennial hostas in a variety of leaf shapes and colors along with annual impatiens.
I hope this gives you some ideas.
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