How does cherry add to glory of Easter?

Easter is a Christian festival which celebrates the resurrection of Christ following his crucifixion. In the poem, "Loveliest of trees, the cherry now," the cherry tree enhances the glory of Easter for two reasons.
The first reason is that the cherry tree blossoms in spring, and thus the blossoms symbolize the idea of renewal associated with that season. The cherry tree is thus an appropriate symbol for Easter because it reminds us of the reason Christ is said to have died. Christ is said to have died for our sins, so that we could be, as it were, born again, renewed.
The second reason is that the color red, implied by the word "cherry," connotes the blood and sacrifice of Christ that Christians remember during Easter. The blossoms of a cherry tree are actually closer to pink in color, but, nonetheless, the word "cherry" still connotes the color red. In the poem, the implied red of the cherry tree is contrasted with the white of the snow. White often symbolizes innocence and purity, and in this context it alludes to the innocence and purity of Christ.