I have an excel work book with several sheets. One is a list of outdoor plants with a column to put an X under the months it blooms. There's a sheet that lists those that attract hummers. Another sheet for butterflies, both nectar plants and host plants with what they host. Also made a sheet with color columns, with the plant names in the columns. One could use different color writing in the page with the month columns, but I didn't like that because you can't sort by writing color.

Another lists indoor plants with columns for various things like light preference, when I got the plant, if it's bloomed, when, color... I couldn't find a good way to add pics but if you upload to a photo-hosting site like imageshack or flickr, you could add a column for links to the photos there.

Taking lots of pics helps a lot too, of whole beds and individual plants, combos you like. I just let the computer make a folder each day I take pics, like it wants to automatically.

I'd rather have my information laid out on paper, not on a computer program. On my page is a link where you can make your own journal.