I use the "My List" feature of this web site to journal my plants. In the comment section of each plant, I include the year I acquired it, where it came from, where it is planted, and sometimes specific care notes or uses. Below that, I keep track of when I can expect the plant to emerge, bloom, change color, go dormant, etc. These dates are approximate and are a range - e.g., some years things emerge earlier or later than others. I am always updating this, and divide each month into 3 parts - early (1-9) mid (10-19) or late (20-end of month). I love the new feature of adding photos specific to my yard which may not be appropriate for the database - e.g., if there are a gazillion bloom photos already in the main database, I don't add any more but do add it to my personal list. I'm currently rather focusing on plant after-care, which I think is difficult to nail down because it can be quite different for different regions.
I also keep a general chore list of things to do or move, etc. This starts as notebook scribblings on garden walk-abouts and ends up in a Word document that is constantly being updated. It is quite specific to my own gardens, so not a particular fit for this site.
