Ever made a bloom calendar? I made a few back in the day – in 1998, 2001 and then this one in 2002, separate ones for the back and front gardens. My goal was to document what times of the year needed more blooms, but it also highlighted plants with very short or very long bloom periods (like the dogwood, versus the Tardiva hydrangea). It also helped me choose when to have visitors see my garden.
(I notice that of the 21 plants shown on this page, I’m now growing only four. No more roses or daylilies, among other discards.)
Now 23 years later and in a smaller garden, I decided to make a bloom calendar this year, using legal pads, pens and pencils again. Old school.
But that changed after reading a recent (free) newsletter from Dr. Jared Barnes that included his article “Creating a Bloom Calendar for Better Planting Design.”
How-To Make a Bloom Calendar

Screen shot with permission.
Barnes introduced me to a MUCH better system – online! – using Excel. (He also suggests software I’d never heard of – Numbers and Google Sheets.) The advantages? Colors, for one! As shown here, you can even use the eyedropper feature to zoom in on photos of the plants to find the right color to represent it on the chart.
He also suggests dividing up the months into three 10-day periods – early (1–10), middle (11–20), and late (21–28+) – rather than the four weeks I’ve used previously.

My blooms in early and mid-March of this year – hellebores, ‘Ogon’ spirea, and assorted daffodils.
More Options
Another approach Barnes uses is to take photos, “maybe this year capture perennials and next focus on trees and shrubs. Or, keep it simple and jot down three or five observations each week to slowly build your list.” With photos, you could later illustrate the results of your calendar – in a blog post, a book, Instagram, whatever.
And why not include some plant characteristics that you’d like to document? For example, a pollinator gardener could indicate which plants support specialist pollinators and which support generalists, to help provide better support for the most critical critters throughout the season. I think I’ll do that myself.
Beyond Blooms…Phenology!
Another take-away from Dr. Barnes’ post is to use the calendar to document phenology, “the study of how organisms respond to yearly cyclical phenomena like climate and seasonal shifts…I study when plants emerge, bloom, and perform in the garden. Then I pair them based on my observations. And, this practice has also allowed me to become more intimate with the land around me.”
Barnes also suggests using “the citizen science National Phenology Network, which lets track the progress of spring and emergence of pests.” Very cool!
For now, I’ll do an updated, colorful version of my old bloom calendar and see what insights I can glean from it. At least it’ll force me to pay even closer attention to what’s happening in my garden, if that’s possible.
Hopefully I can figure out how to use Google Sheets to do the job. Until then, I’m just jotting down plant names and dates into my iPhone’s Notes app.
Susan,
Great, informative, article! Thank you!
J.
Hmmm. I never thought of putting this info into an Excel spreadsheet. I do take notes (some years better than others) with pencil and paper but having that info in a more visual format is very appealing to me. I will definitely give it a go. Thanks for the info!
Thank you very much for this article. I usually just take written notes along with my ridiculous number of photographs.
Susan’n’All,
You can also use Microsoft OneDrive as an adjunctive tool. OneDrive is actually a cloud storage utility that comes free with a Microsoft account. It shows you, via email, pictures you took that day in previous years. You can use those to see what was blooming that day in one or more previous years (Microsoft decides what to send you.) You can select and download whatever photos you want.
If you routinely take snapshots of your garden, (as I do), this serves as an automatic tool to compare today’s blooms with yesteryear’s. You don’t have to do anything other than take pictures and allow Microsoft to back up your documents and photos. (Easy one-time set up).
Of course, the weather from year-to -year heavily influences things. And, this is not exactly the same purpose as a bloom chart. But, it provides an additional point of information for you without you having to do anything special, assuming you normally take garden photos say, once a week.
You can also use this to see how you and your family have aged each Christmas. Mebbe, this is a good thing. Or not.
Great idea to do this as a spreadsheet with such specificity. I make a seasonal version of this for clients, showing what blooms in each season. But this is really a great approach Thanks.