The AGC Blog

Fall Foliage Predictions for Greater Philadelphia 2023

Anticipation is brewing as autumn quickly approaches the Philadelphia region. As September arrives, so do hints of the impending start of autumn—red and golden hues quietly form on treetops throughout Philadelphia’s gardens and arboreta. Each year our member gardens get flooded with questions about the upcoming fall color display—When will the leaves start to change in Philadelphia and how long will it last? You’re in luck! We’ve asked some of the top experts in America’s Garden Capital for their fall foliage predictions for the greater Philadelphia area.

Information as of September 28, 2023. Check back for on-going updates.

An unusually early spring brought an impressive display of cherry blossoms, magnolias, and dogwoods, but will autumn’s vibrant show follow suit? The Old Farmer’s Almanac predicts fall colors will begin early and linger into November, but what does this mean for local Philadelphia fall foliage predictions? Here’s what you need to know:

Mt. Cuba Center

When does fall start?

The Autumnal Equinox (otherwise known as the official start of fall) is Saturday, September 23, 2023 at 02:50 A.M. EDT in the Northern Hemisphere. This marks the period when day and night are roughly equal in length, with nights growing longer thereafter.

What affects fall foliage colors?

In general, fall color is triggered by a decrease in sunlight due to longer nights and shorter days. A wet growing season followed by an autumn with lots of sunny days, dry weather, and cold, frostless nights will produce the most vibrant palette of fall colors. This is especially true of red leaves, such as those on sugar maples and red maple trees.

Did you know: When fall color appears, it is actually the disappearance of chlorophyll from leaves that allows the yellow and orange pigments to be seen.

Haverford College Arboretum

Fall Foliage Predictions from Our Member Gardens

Our member gardens weigh-in on fall foliage predictions for greater Philadelphia:

“Adequate moisture and plentiful sunshine in September and October are the secret sauce.  Also, cool but not a hard freeze nighttime temperatures help enhance colors. Typically the last week of October and the first days of November are peak here in Philly.”—Paul W. Meyer, retired Director, Morris Arboretum and Gardens

“We have a bit of fall color beginning [in late August]. I think it may come early, although that may be wishful thinking in the heat of the summer. We’ve had plenty of rain for a good fall show of colors all over the gardens.”Grounds for Sculpture

“Our garden staff predict that 2023 will be a very good year for fall colors, due in part to a very wet July. Although, the weather in September may change our prediction, depending on the number of very hot and/or dry days we have.Andalusia Historic House, Gardens and Arboretum

Peak fall foliage tends to be last week of October/first week of November. There is great fall color scattered throughout the arboretum through the month of October. —The Arboretum at Laurel Hill

'Out on a Limb' tree canopy walk at Morris Arboretum & Gardens

Where to View Fall Color in America's Garden Capital

You can’t go wrong with an autumn visit to any of our gardens and arboreta, but here are a few favorite spots for viewing fall color in America’s Garden Capital:
  • The Sugar Maple Allee along Memorial Drive at Laurel Hill West.
  • The allée of sugar maples at Cope Field, a ginkgo allée along Meetinghouse Walk, and a variety of trees and shrubs with autumnal interest near the Whitehead Campus Center, Haverford College Arboretum.
  • ‘Out on a Limb’ tree canopy walk at Morris Arboretum & Gardens provides a bird’s eye view of fall foliage.
  • The parking lot at Tyler Arboretum is full of fall show-offs, in particular in the range of oranges and scarlets: staghorn sumac (Rhus typhina), chokeberry (Aronia sp.), oakleaf hydrangea (Hydrangea quercifolia) and smoke bush (Cotinus coggygria).
  • The woodland trails at Winterthur. Here you’ll see notable trees such as dogwood, maple, katsura, hickories, beech, and black gum displaying vibrant seasonal colors.
A vibrant field of goldenrod at Longwood Gardens

Native Plants Contribute to Fall's Show

As autumn color sweeps across America’s Garden Capital, it’s not just the trees that steal the spotlight with their vibrant hues. Native plants of the Philadelphia region, like the New England aster and the goldenrod, contribute to the stunning fall palette. These resilient blooms transform meadows and gardens into seas of purples, yellows, and deep crimson, creating a stunning foreground to traditional fall foliage.

With each passing day, this extraordinary display of color evolves, reminding us of the transient yet captivating nature of the season. Don’t miss the chance to witness this breathtaking collaboration between trees and flowers, a celebration of autumn’s vibrant palette! Find a garden and plan your visit today.