Garden Journaling with Phenology
Posted by Susan M Betz (National Garden Burau), edited by Wedel's on 7th Feb 2025
Anyone in close sympathy with flower and tree and shrub and has a general acquaintance with Nature’s moods could tell the time of year without any reference to a calendar” Gertrude Jekyll, Home, and Garden, Magazine 1900
What is Phenology?
Phenology is the study of natural life cycle and seasonal events in the plant and animal world. These are influenced by the local environment, especially weather, temperature, seasonal change, and climate. Examples include the first dates of budding and blooming flowers, insects hatching, bird migration, and fall color. The word phenology comes from the Greek phaino meaning “to show, to bring to light or make appear.” Phenology is also called Traditional Ecological Knowledge (TEK).
Brief History of Phenology
Phenology dates back thousands of years and is one of the oldest branches of environmental science. Native Americans were experts at reading their regional landscapes. Their knowledge of “nature’s calendar” helped ensure their survival and kept them in harmony with the natural world. For Native Americans, phenology was a well-honed tool and plain common sense. Life revolved around seasonal cycles as they moved from one food source to another, continually modifying their behavior in response to the life cycles of local plants and animals.
They kept track of the seasons by assigning descriptive names to each recurring full moon, alluding to notable phenological events during that month.
- When oak leaves were the size of a mouse’s ear it was time to plant corn.
- The emerging earthworm in March signaled the earth was beginning to thaw, and the time to tap maple trees was not far off.
Phenology offers many benefits to gardeners
Gardening by the calendar can sometimes be misleading, especially when deciding when to plant. Each gardening region has its own native species and seasonal timetable.
Flowers vary in their bloom times depending on their location. For example, Joe pye weed might bloom in August in one area and September in another. But these plants will generally bloom at about the same time in any given locality from year to year.
In addition, biological events are not the same from one microclimate to another. They are influenced by local temperature, precipitation, day length, and proximity to buildings and other structures.
Phenology is valuable for scheduling seasonal tasks in your garden and is a helpful tool for:
- Successful intergraded pest management of insect pests & diseases
- Designing flower beds for sequential bloom
- Planning for harvest season
- Planning gardens for beneficial insects
- Predicting when to plant the best plants for bees and other pollinators
- Preparing for allergy and mosquito season
Tracking Phenology in your garden
Tracking phenophases, the visible stages in a plants or animal’s life cycle, provides gardeners with signals or cues for making good gardening decisions.
Observable life cycle events or PHENOPHASES in your garden include:
- Plant peas when the daffodils or the spring peepers sing
- When the flowers of the bleeding heart or Juneberry trees bloom, it’s safe to plant pansies, carrots, and fennel
- Crabgrass, a creepy pest in the garden, germinates when the soil temperature stabilizes at 55 degrees and coincides with the bloom cycle of forsythia and the perfect time to apply fertilizer to your garden.
- When you see milkweed pods and plumes of goldenrod, it’s time to finish harvesting and dry herbs for the season.
Insects as weather prophets
Insects, spiders, and other crawling or flying creatures are vital to healthy gardens. They perform important jobs pollinating, recycling nutrients, and eating pests.
Additionally, according to an article published in the New York Times in the 1900s, “It is from the habits and instincts of animals properly observed that we can learn more weather wisdom of the scientific sort than from almost any other source, and of all animals, insects are among the most interesting to study in this connection.”
Spiders:
- These creatures cannot spin properly in high wind.
- Before a gale, they may be observed strengthening their webs.
- The shape of the web is also a valuable weather indication. When the frame lines are short and stout, the insects’ instinct tells it that wind and rain are coming; while long and slender frame lines are a very reliable sign of calm and fine weather.
Bees:
- There is a saying that “a bee is never caught in a shower”
- When rain is impending, bees do not go far afield but ply their labor in the immediate neighborhood of their hives. This well-authenticated fact is set forth in the rhyme, which tells us that: When bees to distant wing flight, days are warm, and skies are bright, but when their flight ends near their home, stormy weather will surely come.
If you keep a garden journal for seed lists, plant names, and locations, include your observations of the phenophases and microclimates unique to your garden and landscape.
Be sure to note:
- First and last frost dates
- Bird arrival dates
- Leaf out dates
- Insect emergence
- Blooming dates of native and non-native species, including trees, shrubs, flowers, herbs, weeds, and ornamentals. Early spring, mid-late spring, early summer, mid-summer, late summer, and fall
- High and low temperatures and precipitation
- Moon phases, summer and winter solstice, and equinox dates
To learn more about phenology and contribute the information collected and recorded from your local garden to educate others, please check out the following sites.
After all, “More grows in a garden than a gardener sows.”
By: Susan M Betz, National Garden Bureau, https://ngb.org/phenology/