How Weather and Daylight Influence the Color of Leaves

Starting in spring, temperatures begin to warm, and days grow longer. Longer days mean more hours of daylight, and daylight is essential for photosynthesis, the process that allows all plant life to convert water and carbon dioxide into the sugar and carbohydrates that fuel and energize these life forms. Chlorophyll, the substance that makes leaves green, is produced in abundance during spring and summer because trees and shrubs are using energy from carbohydrates they produce from soil nutrients and water, to put out their leaves and set new buds that will become the next year's leaf growth.
The U.S. National Arboretum explains that starting at the end of summer, and continuing into early fall, deciduous trees and shrubs enter a new growth process. This growing stage is just part of the process that allows the trees and shrubs that lose their leaves during winter, to enter the phase of changing colors that is one of the things people enjoy most about autumn, and one of the things that makes it such an interesting season, even though summer flowers are past their prime, and vegetable gardens have slowed fruit production or stopped it altogether.

So What Should I Plant?

Sugar Maple (Acer saccharum)
A quintessential fall favorite, sugar maples are reliable growers that consistently produce fantastic fall color. Their display is so spectacular that few trees come close to matching the beauty of their showy fall leaves. Leaves on this variety of maple gradually change color. They go from red to orange, and finally yellow. Sugar Maple is hardy in USDA hardiness zones 4 through 8. This North American native grows in sun or shade, but needs soil that drains well. It reaches a maximum height of 70 or 80 feet. While it can grow in partly shady conditions the leaves get brighter and more vibrant colors when grown in full sun.
Ginkgo (Ginkgo biloba)
Ginkgo trees are known as living fossils because they are the last living ancestors of tree varieties that existed 200 million years ago. The tree is sometimes called a maidenhair tree because of their fern-like fan-shaped leaves. Although they don't have needles, they are still related to conifers.
Ginkgo trees are not native to North America. They are considered hardy in USDA zones 4 through 9. They can grow to between 30 and 80 feet wide. They can grow to 100 feet in height. These trees will grow in sun to shade, as long as the soil has adequate drainage and can hold moisture, because Ginkgo likes moist soil. It is a slow growing tree.

Other Trees:

Amur maple (Acer ginnala)
flowering cherry (Prunus spp.)
'Bradford' flowering pear (Pyrus calleryana 'Bradford')*
white oak (Quercus spp.)
smooth and staghorn sumac (Rhus glabra and R. typhina)
sassafras (Sassafras albidum)
Japanese maple (Acer spp.)
bald cypress (Taxodium distichum)
sweet gum (Liquidambar formosana)
sweet birch (Betula lenta)
stewartia (Stewartia spp.)
serviceberry (Amelanchier spp.)

Best Shrubs for Fall Color

Chokeberry (Aronia arbutifolia)
Chokeberry is a shrub that is native to North America. It grows to a height of 10 feet
and a width of 6 feet. In late summer, and continuing into fall, Chokeberry produces deep red berries. During fall, the leaves burst with bright red-orange and a mixture of both colors.
'Winterthur' Smooth Witherod Viburnum (Viburnum nudum 'Winterthur')
'Winterthur' viburnum is hardy in USDA zones 5 through 9. Native to swamps, thickets, and woods, its growing range extends from Texas and Florida to Connecticut. It will grow in full sun to part shade, and likes wet to moderately wet soil. 'Winterthur' starts to show its color in late summer. Before the full color show explodes, the 12-inch clusters of blush-pink berries gradually turn to the color of bubble gum before they turn to a deep blueberry color. The colorful berries contrast against the glossy leaves that are an infusion of maroon and red.

Other Shrubs for Fall Color

Burning Bush (Euonymus alata)*
'Grow-low' fragrant sumac (Rhus aromatica 'Grow Low')
Highbush Blueberry (Vaccinium corymbosum)
Virginia Sweetspire (Itea virginica)
Smoke bush (Cotinus coggygria)
Spicebush (Clethra alnifolia)
(*Editor's note: these woody ornamental are known for beautiful fall foliage, but they also have some serious drawbacks in many regions. Do your research and carefully consider whether to introduce them to your garden.)
By planting trees and shrubs that produce brightly colored leaves in autumn, you can extend the interest all over your property, long past the end of the traditional garden growing season. Colorful leaves coincide with fall harvest, so not surprisingly, these earthy, natural colors are often part of a fall and holiday decorating theme.