This is a photograph of pea flowers. When thinking of a pea plant, a person may not focus on the flowers. It may be more usual to focus on the plants as a whole or the peas. The flowers could possibly be seen as just a stage before the peas and not be seen as having any significance themselves. This photograph however, focuses on the flowers.
One way this photograph can inspire poetry, is by inspiring a poet to look for the overlooked in something. For example, a poet might see a photograph of a wedding party. Rather than focusing on the bride or groom, their family or guests, a poet might choose to focus on one of the wait staff in the background. This might provide a new perspective. This same idea could apply to many situations.