You need to plant annuals every year but they flower all summer and do fine in pots if enough water is provided. Assuming it is a sunny area then there are lots of choices. Geraniums, Ivy geraniums, vinca vine, spike plants, marigolds are just a few durable low-maintenance annuals that pop to mind. There are many more choices. Look at the tags and seek out plants for sun. Naturally you can ask the folks at Hewitt’s to make suggestions based on what is in the greenhouse at the time you visit.