Phenology? What’s That?
Phenology, if you’ve never come across the term, is the science (or perhaps art) of tracking natural occurrences and changes over a long period of time, to discover the patterns and rhythm of them, in order to learn from them. It is one of many good reasons to keep a garden notebook, so you can develop an accurate phenology of your own unique ecosystem.
When You Hear the Peepers, Plant PeasSo we are planting our peas earlier than usual, because the peepers started peeping earlier than usual. What the peepers actually tell us, I think, is that the soil temperature has warmed sufficiently for them to come out of hibernation. Soil temperature is a good indicator of when to plant, as the soil warms up much less quickly than the air, and a week of unseasonably warm weather doesn’t affect it quite as much. But the indicators that are strongly affected by air temperature are not as reliable during abnormally warm weather. For example, my Cornelian cherry usually blooms about three weeks before the forsythia. This year it beat the forsythia by one measly day. The Juneberries, aka as shadbush, usually bloom in May. They’re already blooming, sadly. (The month of May could be bereft of May flowers.)
Develop Your Own Very Local Phenology
I didn’t have any garden to-do’s associated with the Cornelian cherry, the forsythia, or the Juneberries, so they’re not messing me up. I do have a good idea of when our last frost is, and counting back from that is probably still the best guide to when to plant things. Of course, the more years you’ve been gardening in the same place, and recording this date, the more accurate you will be. Nature Calendar is an interesting phenological source for those of us in hardiness zones 4-7, east of the Mississippi. If you haven’t spent much time in your present garden, it can help you pinpoint where you are in the cycle of seasons. You can also peruse an earlier post I wrote on phenology, which had observations I had collected from a variety of sources. It frustrated me then, and still does, that many of these maxims either do not agree, or are not precise enough to be helpful. But if you have nothing to go on, they can be a good place to start.
Do you use phenology to direct your vegetable garden planting, or guide you in other garden chores? I’d be interested to hear of your observations.
UPDATE: Just discovered the USA National Phenology Network.
*Quote attributed to Mark Twain