You can add images to the database using the link if at the top of page. Search for the correct plant and on the left of the entry is the link to upload photos. If you are unsure of the cultivar names, there are generic entries you can add them to.
Under the Community menu, also found at the top, there are various plant specific forums where you can also share your photos or you can start a thread in
Garden Photos Forum where members share their gardens.