Flowers are sorted first by color.

Regular-shaped flowers are sorted by number of petals/sepals from 3-12, then daisy-like flowers with more than 12 petals.

The next groups are in alphabetical order:
bell – flowers in a bell or trumpet shape 
cluster – very small flowers in group
irregular – odd-shaped flowers 
globe – group of small flowers that seem to be a globe shape
spike – tiny flowers or a single bloom that is a spike
shrub/tree – flowers on a bush or tree
vine – flowers on a vine

Within each category, the photos are in alphabetical order except where similar blooms are next to each other for comparison.

This is a work in progress!