The main symbol is Elisa's flowers (the chrysanthemums). They symbolize Elisa's passion and love of aesthetic beauty, which her husband cannot see in the flowers OR in Elisa. Elisa tends to her chrysanthemums with great care and effort, which symbolizes how she longs to have her husband share her love for them and how she wishes he could recognize both their beauty and her own beauty.
Another symbol is the fence that surrounds her flowers/garden/property. Elisa is isolated from the rest of the world; however, she wants to venture out and see it. This is part of the reason she becomes interested in the Tinker who tries to get her to give him some pots to mend. He has traveled all over the area and has seen places Elisa would like to see, so the fence is a border between Elisa's world and the outside world she will never truly be a part of.