There are a myriad of reasons for loving New England in the fall, but I suspect the vibrant colors of the autumn foliage is a popular one. Maples in their fluorescent oranges and reds, ash leaves dipped in burgundy and the brilliant gold birch and poplar foliage close out the growing season with color explosions often as vivid as those Fourth of July fireworks.
Most of us learned in high school science classes that leaves are green because they produce chlorophyll, which is the essential component that allows the leaves to turn sunlight into the carbohydrates they need to sustain the plant.
Normally, the cooler and shorter days of autumn slow the production of chlorophyll and the other compounds in a plant’s leaves become visible, hence the yellows, reds and oranges. The red color is due to a compound known as anthocyanin. It is an anti-oxidant that is typically produced during the fall, or earlier, as stored sugars are broken down. Orange and yellow pigments, carotenes and xanthophylls, respectively, are always present in the leaves, but they are masked during the summer by the abundant chlorophyll.
The record amounts of rainfall many of us received this summer have done wonders for our lawns but have stressed out other plants, depending on where they are situated on the landscape. Trees in wetter areas are contending with higher water tables for longer periods of time and have, in many instances colored up early. More upland trees grew well with all the rain as well as the warmer early fall temperatures and many are still retaining their green leaves. A few seem to be shedding before they turn any color and that is probably due to the excessive rain as well as warmer than usual nighttime temperatures.
According to the Connecticut Department of Energy and Environmental Protection, since the summer rains are keeping the leaves on many trees greener longer, we are seeing peak colors now in the northern corners of the state. Central Connecticut should peak between Oct 16 and 30, with the southern portion coloring up most likely starting Oct 26.
Aside from just savoring the view, the colorful leaves are a quite useful addition to home landscapes and gardens. Leaves are an excellent source of free organic matter. When soils have adequate amounts of organic matter, they are able to store more water and nutrients. They have better structure and drainage, and the organic matter provides plants with some nutrients as well as serving as a food source for soil organisms.
There are several ways to incorporate leaves into your yard and garden. If the leaves falling on lawn areas are not too thick, they can just be run over with a mulching mower or even a regular lawn mower and left to decay on the lawn. Just like leaving the grass clippings down, this is a slow but sure way to add organic matter to established lawn soils.
For areas of lawn thickly coated in leaves, they could be collected in grass catchers as the lawn is mowed and then used to mulch garden or shrub beds. Or leaves alone could be raked up and shredded and the shredded leaves placed around perennials and shrubs, or even be used as a winter blanket over the cleaned vegetable garden.
Leaves, either shredded or whole, could be corralled into a area with some kind of barrier to keep them from blowing away and piled and left to decompose on their own. The leaf mold that forms on the bottom of the pile over a year or more could then be incorporated into beds before planting in the spring or as perennials are added or divided in flower beds.
Fall is a great time to either start or reinvigorate the compost pile. Leaves provide much needed “browns” to the pile and ideally should be mixed with “green” material such as kitchen scraps, undiseased garden debris, grass clippings or even some blood meal or alfalfa meal if no other high-nitrogen sources are available. There are many informative books and fact sheets available on composting that one can go to for directions and advice.
The finished compost can be mixed into garden-bed soils before planting or used as a top-dressing to add nutrients and organic matter to established beds. It is always a good idea to test the soil after adding organic amendments to see what else might be needed for optimal plant growth.
Enjoy the fine New England foliage, and when it falls in your yard, think about ways to recycle it and put the leaves to good use.
For questions on managing fall leaves or for other gardening questions, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.ladybug.uconn.edu or contact your local Cooperative Extension center.