Mt Cuba Center
Mt Cuba Center
Back to News Updates – October 26, 2020


Fall Foliage Bursts into Color

Every autumn has its own rhythm says Bill Trescott, Mt. Cuba Center’s arboriculture manager. Weather conditions, temperature shifts, and mother nature all factor into when the best fall color will show through.

Mt. Cuba’s native sweet gums, birches, sourwoods and black cherries are already putting on a show and our arborists predict fall foliage will peak in the next week and certain species will continue their autumn display well into November.

Read on to find out the top factors leading up to this year’s colors and the best places to spot fall foliage in the gardens.

Frog in pond at Mt. Cuba

Changing Colors

Each spring, leaves contain green, orange, and yellow pigments. Green is the dominant hue through spring and summer due to chlorophyll production. In autumn, orange and yellow hues are revealed as chlorophyll breaks down and is not replaced. Red and purple colors are created in a separate chemical process that is tied to the cessation of chlorophyll production as well.

A myriad of factors influences fall foliage with the top considerations being day length, rainfall, sugar accumulations in the leaves, wind, and just the right mix of cool, bright, and sunny autumn weather. The brighter the light during early autumn, you can almost guarantee a greater production of fall pigments.

When the days of autumn are sunny and cool with chilly (but not freezing) nights, this can lead to the brightest colorations. This is when the production of chlorophyll slows down as deciduous trees begin their preparation for winter.

The green pigments in leaves start disappearing as sunlight hours decrease. This allows the reds, oranges, yellows, scarlets, and purples to come to life.

Spotting Fall Color at Mt. Cuba

While you’ll find mountainsides full of expansive swaths of fall color in the Northeast, Delaware is not exactly known for its mountain ranges. What you will find is a miniaturized version of this on the slopes in Delaware’s Piedmont region. As a result, individual trees with stunning color really stand out and steal the show. It is usually something different each year, but there are always a few trees that command your attention. They glow in the midst of all of the more subdued colors around them.

Visiting Mt. Cuba in fall makes for a unique experience since our gardens give visitors a chance to get up close and personal with fall foliage. The quick succession of rolling hills while driving up to Mt. Cuba will give visitors a sneak peek of what’s instore. Once visitors get in the gardens, the diversity of trees starts to pick up.

“That changes how things color up,” Trescott said. “It shakes up the possibilities when you have a curated collection with so many different species and cultivars.”

The topography at Mt. Cuba allows visitors to get closer to their favorite trees, with something different coming to life around each twist and turn through Mt. Cuba’s woodland paths.

Autumn arrangement by Raymond Carter.

2020 Weather Influences at Mt. Cuba

“I first thought we were in for an excellent year because of cool weather in September, but the dreary weather the past few weeks may have slowed that process down,” Trescott said. “Plus, Mt. Cuba has vast variety of trees make it harder to predict peak foliage because they will change color at different times.”

Our arborists are seeing that fall color is delayed across certain species. While certain trees like our ashes are right on target, others like black walnuts are way off target and the beech trees are expected to go straight to brown.

As more intense weather events become common in northern Delaware, they can take the edge off of a spectacular fall display. If soil is waterlogged and stays that way for quite a while, it can block oxygen flow to roots and lead to physical damage to leaves.

“I think one of the things people miss with big weather events is that they do really affect tree color in fall,” Trescott said. “When you have those intense winds, leaves get damaged and shredded. If 30 to 40 percent of leaves are lost or damaged in a wind event like they were in this summer’s tropical storms and August’s tornado, that makes a difference. The crowns can become very thin.”

Get up close and personal with fall foliage at Mt. Cuba through November 22. The garden is open Wednesday through Sunday from 10 am to 6 pm in October, and 10 am to 4 pm in November. Visit for more information.