As you watch the rivers swell with the melting snow of winter and you feel the temperatures warm with the onset of spring, know that many plants and animals are paying close attention to these factors as well. The science behind these correlations determines the timing of many events in the environment. Phenology is the study of these events, specifically the relationship between life-cycle events of plants and animals as they are influenced by climate, habitat, and seasonal change.
Phenology is derived from the Greek word phaino meaning “to show, to bring to light, or make appear” indicating its principal concern with the dates of first occurrences of natural events in their annual cycle. Examples include the date of emergence of leaves and flowers, the first flight of butterflies, and the first appearance of migratory birds, as well as the date of leaf coloring of deciduous trees in the fall, the dates of egg-laying of birds and amphibian, and the timing of the cycles of honey bee colonies. Most of us are novice phenologists as we often notice when the birds return, our bulbs are up, and the trees leaf out.
You can time many of your gardening practices by observing these events, whether it be planting seeds or watching for destructive insects.
Here’s a great chart from www.gardening.about.com
| Plant peas | When forsythia & daffodils blooms |
| Plant potatoes | When 1st dandelion blooms |
| When the shadbush flowers | |
| Plant beets, carrots, cole crops, lettuce and spinach | When lilac is in first leaf |
| Plant beans, cucs and squash | When lilac is in full bloom |
| Plant tomatoes | When lily-of-the-valley are in full bloom |
| Transplant eggplant, melon and peppers | When irises bloom |
| Plant corn | When apple blossoms start to fall |
| Seed fall cabbage and broccoli | When catalpas and mockoranges bloom |
| Seed morning glories | When maple leaves reach full size |
| Plant cool season flowers (pansies, snapdragons…) | When aspen and chokecherry trees leaf out |
| Watch for: | |
| Eastern tent caterpillars to hatch | When crab apples start to bloom |
| Gypsy moths hatch | When the shadbush flowers |
| Squash vine borer eggs are laid | When chicory flowers |
| Mexican bean beetle larvae hatch | When foxglove flowers open. |
| Japanese beetles arrive | When morning glory vines start to climb |
