Evelyn,
I don't use a computer program specifically for gardens as such. I use Excel and list the iris alphabetically. Excel is very good as I can insert rows to enter a new iris when I buy one and also insert rows to expand an entry per iris for each season. Pretty soon I'm just going to have one Excel sheet per iris, but I'm not there yet.
I know that other people on the forum who also use Excel can sort their entries by hybridizer or whatever but I didn't set my lists up that way.
I'd be happy to e-mail you an example of what I have.
