Phenology is the study of plants and animals through the seasonal changes. Those of us who love nature often notice these signs and signals, where one event leads to the next through the weeks and months of each year, and cycles of life.

Also, see how the Fibonacci sequence appears in plants we have in our gardens.

Phenology in the Garden

If you like to spend time in the garden (or outdoors in general) you probably already notice various signs and signals that indicate natural seasonal changes are underway.

What triggers the budding of leaves, the blooming of tulips, or the mating calls of peepers? Why do they start on one day and not another? And which circumstances lead up to these natural events?

What is Phenology?

The word phenology has two parts—pheno (appearance) + logos (study)—the study of plants and animals through seasonal changes.

We see it in everything from budding, flowering, and fruiting, to breeding, nesting, and migration.

By paying attention and recording your observations (see checklist below) you can not only become a more proficient gardener but assist with national volunteer projects that collect this information to give us a better understanding of nature and climate change.

To get started, this short video shows how climate change causes natural cycles to get out of sync:

Nature: It’s All Connected

One of the coolest things about being a gardener (or avid nature lover) is how, over time, you start to notice the profound relationships between living things and the timing of their events. It’s like the ultimate symphony made up of domino effects.

If you live in a cold climate like I do, we hold it all together until late winter. And then we go bonkers waiting for spring. Parades are held when one lone robin makes an appearance. Never mind he was here all along!

The quest to find signs of spring actually begins back in December with the increase in daylight following winter solstice. It’s still freezing outside but the days start to get longer and we know winter cannot outsmart the sun and the tilt of the earth forever.

Several months later, snow gradually melts, we start tapping the trees for sap to make syrup, tree buds start to open, insects appear, and spring fever (the people’s euphoria) sets in.

With insects come the birds, frogs, and bats that feast upon them.

Tree leaves fill out and baby birds hatch in their nests, nicely hidden from predators.

Fledglings leave the nest when food sources are abundant, giving them their best chance to succeed on their own.

These are just a few examples, of course. And on and on it goes: everything works in harmony.

Nina Leopold Bradley describes it beautifully:

It’s not just the natural events themselves, but the correlation between them that we see: there’s perfection in the timing that we cannot afford to tamper with without risking incredible, irreversible losses.

Phenology is What We All Do

Phenology is not magic or woo-woo, but, quite simply how nature works: adapting to climate and weather; acting on favourable conditions.

Birds aren’t going to migrate until there’s food sources available at their next resting places.Bats aren’t awakening from their winter’s rest until there’s lots of insects to gobble up in the air.Peepers don’t peep until their intended mates are also out of hibernation and ready to rumba.Apple trees produce flowers and then fruit when the conditions are favorable for pollinators and then ripening.Bees are most active when nectar and pollen is abundant.

How Gardeners Use Phenology

As gardeners, phenology can help guide our planting schedules along with other practical information like our last frost date and the individual planting recommendations on the seed packet or plant tag.

Seasons are our biggest hint, of course. Watching spring unfold never ceases to stir up the desire the start working in the garden. And, imagining a time with limited garden how-tos, you can see how advice based on observations in nature may have seemed helpful.

There are hundreds of these old-fashioned garden sayings based on natural events like the timing of buds and blooms. Some of them are very specific to particular regions and do not apply to other.

For example, plant peas on St. Patrick’s Day may work in regions much farther south than I am, but here in Ontario, Canada, the only thing I’d have if I planted pea seeds outdoors in mid-March is frozen peas.

The saying plant peas when the daffodils bloom does not take into account the fact that there are numerous types of daffodils with a wide range of flowering times from late winter to late spring, so that doesn’t really help. Plus, an early warm spell can get them flowering in winter and that would not be the time to sow those seeds.

That said, it is true that you may find yourself sowing pea seeds at the right time and the daffodils may also be in bloom. But it’s not a infallible rule to sow by.

Old-Fashioned Garden Advice: Does it Work?
covers a bunch of these old sayings and puts them to test.
Have a look to see how reliable they really are.

One expression I do find reliable is the birds will tell you when it’s time to save seeds.

This happens in the fall. I know it’s time to start collecting seeds when the birds start dining on old flower heads on sunny afternoons. I can tell by their enthusiasm that the seeds are getting nice and toasty and just right for seed saving.

Related: Natural Signs it’s Time to Plant Fall Bulbs

Ideas For Keeping Your Own Phenological Records

By noting our observations, we become more aware. Sign up with an phenology organization or simply start jotting down your own notes. I’ve listed some suggestions below. You can adapt it to suit your growing region. It’s much the same as a garden journal with some notes about seasonal natural events added in. It’s very interesting to compare notes year after year to see how things change and to better understand what timing works best in your garden.

Spring to fall: record the dates, any unusual weather, and take photos 

Last frost dateFinal melting of ice and snowTrees start budding out (pick a particular tree type to observe)Trees leafing outTrees leaves fully openFirst trilliums in the woodsTulips 2″ out of groundTulips bloomingApple and plum tree blossoms fully openLilacs budding and bloomingPoppies in bloomIrises in bloomDelphiniums in bloomAsters in bloomFirst worms out of soilFirst male cardinal mating callsFirst robins (several) in gardenFirst peeper mating calls (this can vary by many weeks: it’s very interesting!)First bats swooping for mosquitoes in the eveningsFirst baby toadsFirst beesFirst hummingbirds, Baltimore orioles, and Rose-breasted grosbeaks at feedersFirst butterflies and mothsFirst tomatoes ripeFirst frost (at end of season)Also note any unusual weather / temperaturesRecord the planting dates of all annual veggies and how successful the crops were

Resources for National Phenology Groups in the U.S.

These are just a few of many. Try Googling to see what’s available in your area.

Are You Ready?

This topic is so huge (as huge as nature itself) but I hope this has given ideas for your own phenological studies. Have fun with it and perhaps you’ll come up with new garden widsoms to pass along to your grandkiddles.

~Melissa the Empress of Dirt ♛