For the beginning gardener living in the Midwest of the U.S., the colocasia plant is a good choice since this annual grows quickly, which would allow the novice gardener to see results in no time. This plant goes by the nickname "Elephant Ears," since that's what it comes to resemble once it has grown to its full height of 8 feet (2.4 meters).
If you're looking for an eye-catching annual that also emits a lovely scent, then the lavender plant and flower is for you. The lavender is famous for its purple color, and its smell has the additional benefit of keeping pests away, since they don't like the scent. However, the lavender is a relatively delicate flower, so moisture and sun requirements need to be strictly followed. In contrast, the angelonia is a flower that's both heat- and drought-tolerant, making it an ideal annual to plant in the Midwest. Similar to the lavender, the angelonia gives off a pleasant scent that's been likened to the smell of grape soda. Another hearty Midwestern annual is the scaevola. These flowers are often used as hanging plants or in pots. Scaevolas are so low maintenance that they've been called "New Wonder."
If you're looking for a flower that can multi-task, then the verbena flower is something to consider. This Midwestern annual can be used as a trailing flower or a mounting type of flower. Also, the verbena comes in both soft pastels as well as vibrant colors, so the choice is yours. The only serious type of maintenance that this flower needs is "deadheading," which entails continually cutting off dead blooms so as to allow the plant to re-flower.