A quick iPhone photo of the first daffodils to appear in the garden this year. I noticed them coming up about a week ago, but just saw these as I stepped outside to take some video of the street resurfacing that is happening on our street.
Adding the bloom date to my Google Calendar-based gardening journal. I put in an all-day event that then repeats yearly, forever, so that I can see what happens when at a glance.
You can try this yourself. Add a secondary calendar to Google Calendar (or whatever electronic calendar you use) and then add in events as they happen. If you have historical data, you can go back and add some of that in, too.