Donald, it's very easy to upload photos to the database. I'm not real good at explaining stuff but I'll try.
Find the plant in the database, for instance Cupid's Bower (Achimenes longiflora)
Scroll all the way down towards the bottom of the page to where you see a box that says:
Click on: Upload a photo
Click on the green box that says Upload an image.
Find the photo on your computer and select it. It will take just a minute to load and then you will see a thumbnail of your photo on the top right and a box on the left side of the page that asks "What type of image is this?" Click on entire plant, bloom or leaves etc. (whichever one the photo depicts) then click on the green "Finished" button.
The photo will go into a queue for the database moderators and you will get a system message once it has been approved.
Hope this helps but if you have any questions at all, please don't hesitate to ask.