Over The Fence Newsletter Bucks County Cooperative Extension

Fall is for Planting
By Scott Guiser, Extension Educator/Horticulture

Fall is for planting…that was an advertising headline developed by the American Nurserymen's Association about 25 years ago. And it is true. Fall is an excellent time to plant trees, shrubs, bulbs and lawns. Even novice gardeners are aware that fall is the time to plant spring flowering bulbs. But many gardeners are missing a great opportunity to establish other ornamental plants by taking advantage of this great planting season.

Think for a moment about the environmental conditions that exist in the fall. Days are getting shorter and cooler, moisture for developing roots is more reliably available, soil is still warm from months of summer heat. Roots continue to grow long after above ground plant parts appear dormant and air temperatures are below freezing. All of these conditions are ideal for the establishment of trees, shrubs, grasses and other ornamentals. Let's look more closely at some examples.

Lawns. Experts agree…without a doubt, fall is the best time for establishing a new lawn or even to re-seed thin areas. The factors described above come into play. Soil is warm, moisture is plentiful (usually), air temperatures moderate and maybe most importantly, weed pressure is declining. Nasty, competitive weeds like crabgrass are declining and die with the first frost while cool season grasses such as perennial ryegrass, Kentucky bluegrass and fine fescues thrive under cool, even frosty conditions. As an added bonus, lawns established in the fall will have two cool growing seasons (fall and spring) before experiencing the stresses of summer heat. Contrast this with conditions that lawns established in the spring experience, and the advantage of fall seeding is clear. Actually, there is nothing wrong with getting started on lawn renovations and revitalization in late summer. The Labor Day time frame is ideal. The sooner you plant, the longer the new seedlings have to establish. The official cut-off for fall seedings in Southeastern PA is October 15 but seedings made as late as Halloween usually do fine.

Fall is also an ideal time for other lawn care practices, especially fertilization. If you only apply fertilizer once a year, September should be the month. About 15 lbs. of a 10-6-4 fertilizer per 1000 square feet of lawn is recommended. Use a fertilizer with a portion of the nitrogen in a slow release form. Aeration, de-thatching, liming and broadleaf weed control are all in order for fall, too. Translocated herbicides for dandelion, clover and other lawn weeds work best now because they are transported to underground weed survival structures. For more information about fall lawn care give us a call or visit Penn State's web site at:
http://turfgrassmanagement.psu.edu/homelawns.cfm

Trees and Shrubs. Research has shown that many deciduous plants continue root growth in the fall, long after air temperatures and day length stop leaf and shoot growth. So, why not plant trees and shrubs in the fall? While you will not have the gratification of seeing the instant bloom and growth that occurs following spring planting, you will have plants well established and ready to roll next spring. That means better growth and less stress in 2008. Of course, be sure that the plants you establish this fall are of high quality and have not been abused by poor handling over the summer in the garden center. Be choosy about what you select. Also, certain species such as Magnolia, Tulip tree, Sweetgum and others are reported to be intolerant of fall planting.

Although moisture demands for fall planted trees and shrubs is less than those that are spring-planted (cooler temps, less transpiration), be sure to water thoroughly at planting time, and as needed, so that the plants never get drought stressed. And don't wait until December 24 to plant. The sooner fall planting is completed, the quicker it will become established. Perhaps the guidelines for turf seeding (be done by mid October) also apply to trees and shrubs.

Fall fertilization for trees and shrubs also makes sense. Because roots continue to function long after leaves drop, they can absorb nutrients. Don't worry about stimulating new growth on tree and shrubs by fertilizing in the fall. By the time you see fall foliage loosing the green of summer, the plant will not resume growth even if fertilizer is applied. Never apply fertilizer to frozen ground. Once again, let's get this job done before mid October.

Bulbs. If you want that flash of color from tulips, daffodils, crocus and other early spring bloomers you have, plan ahead and fall plant. An investment this fall always pays-off in a big way next spring…something to think about on those long cold winter nights. Daffodils and crocus are reliable re-bloomers but tulips perform like annuals under our growing conditions. You probably have several catalogs right now and the garden centers have their shelves stocked with the latest cultivars. A friend tells me there are saffron crocuses to be had. It is not an exaggeration to say that there are hundreds of cultivars of the spring blooming bulb species. And when you say tulip, remember that it is not just one species.

So, fall is for planting…get to work!

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MASTER GARDENER CORNER

While Master Gardeners are always happy to talk to other gardeners, there are many ways to learn more about gardening. We have 3 Nature Centers right here in Bucks County: Churchville, Peace Valley and Silver Lake. Bowman's Hill Wildflower Preserve in Washington Crossing is a Bucks County gem. They all offer great classes that are open to the public. Also, there are more than a dozen local garden clubs, a great place to learn from other gardeners. We receive so many calls inquiring about garden clubs we started a list with meeting times and locations. If you belong to a garden club that is not on our list, or if you would like to join a garden club, please contact our office at Extension. Don't forget to check below for area horticultural happenings.

Horticultural Happenings

Perennial Plant Conference, Friday, October 19, Lang Performing Arts Center, Scott Arboretum of Swarthmore College. This day-long annual conference covers a variety of topics of interest to horticulturists and avid gardeners. A brochure can be downloaded from the following website:
http://www.longwoodgardens.org/docs/ppc_brochure.pdf
or call Longwood Gardens' Continuing Education Office at 610-388-1000 extension 507,
Monday - Friday, 8 am - 4 pm.

Fordhook Farms Open House, Doylestown, PA, September 21 & 22 (Friday and Saturday) with lectures by Michael Dirr both days. Go to http://www.heronswood.com and click on Fall Open Event., or call 215-345-1766 for more information.

Weed Control Tips

Herbicides that move within the weeds (translocate) are especially effective on perennial weeds because they move throughout the plant, even to underground parts, and disrupt plant functions. Roundup is the trade name for an herbicide that contains an active ingredient called glyphosate, and is one of the most widely used herbicides. There are many other trade names for this active ingredient so feel free to shop for a "generic" brand if you choose to use it. Glyphosate, when applied properly, will control almost all perennial weeds. Here are the key points to keep in mind when using glyphosate products.

September / October 2007