By C. Rae Hozer
Nature’s timing for plants in springtime is not tied to the month or date as much as to hours of daylight and darkness and to the effects of air and soil temperatures. Persistent warming affecting the continental United States and other parts of the planet has now created a disconnect between typical lifecycles and normal interaction between plants, animals and insects. Science Daily’s website containing news from universities, journals and other research organizations (accessible by typing the following into your computer browser: http://www.sciencedaily.com/releases/2013/01/130116195344.htm) recently announced studies which show spring flowers are blooming up to a month early in the eastern U.S.
The stage of spring plant development at the time a freeze strikes is of critical importance to plant health and fruit production. Tennessee had summer-like temperatures from the get-go in January 2012 combined with a mild November and December at year's end. Daffodils growing beneath trees near the southwest-facing end of my driveway bloomed in mid-January last year and earlier (New Year’s Day) this year. Daffodil stems, leaves and flower buds can usually withstand a freeze. However, their stems bend and the blooms are ruined if the daffodil flowers are open when a freeze or heavy snow occurs. Peak blossom of fruit trees was early in 2012 in many parts of the country. Spring frosts and freezes which occurred then seriously harmed cherry and peach crops by disrupting the normal bloom-fertilization-fruit-set sequence.
Summer-like temperatures occurring too early can impact cool-season vegetation. Heat shuts down plant growth and/or interferes with normal blossoming, fruit and seed set in crops like Chinese peapods, lettuce, spinach and broccoli. Lawns made up of turf varieties like KY bluegrass or fescue blends best utilize fertilizers applied during autumn months (September, October and November). Lawns of this type become semi-dormant when the weather turns hot and dry.
Early onset of summer-like temperatures can mean nitrogen applied in April ends up feeding summer lawn weeds rather than the turf it was intended to help. In the past two years, I fed my cool season turf earlier (in February rather than during March). Mowing high (at the top of the recommended level for the turf type you grow) also helps encourage a healthy stand of grass and discourages weeds when the mercury climbs.
Contact your local University of Tennessee Extension office if you wish to become a Master Gardener. Volunteers take about 40 hours of Master Gardener (MG) training. After attending 2013 MG classes, trainees then donate 40 hours of horticulture-related community service to become certified Tennessee Master Gardeners.
I typically present the MG botany class in Cumberland County. Botany is the scientific study of plants and the plant life of particular regions, habitats or geological periods. The plant physiology part of that course explains various aspects of plant life — nutrition and metabolism; growth, development and reproduction; as well as responses of vegetation to environmental factors. Botany concepts are used when selecting climate-appropriate varieties; in planting, nurturing and pruning of ornamental plants or fruit and vegetable crops; as a basis for care decisions such as how and when to fertilize or not fertilize; in understanding the part sunlight, soil, and moisture conditions play in making certain spots around your home more suitable for particular nursery specimens than others. Botany also helps when diagnosing plant problems and suggesting remedies.
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Plateau Gardening is written by Master Gardeners for gardeners in Tennessee’s Upper Cumberland Region. Contact UT Extension Cumberland County at P.O. Box 483, Crossville, TN 38557 (484-6743) for answers to horticulture questions, free publications and how to become a Master Gardener. Send email comments or yard and garden inquiries to Master Gardener Rae, MGardenerRae@frontiernet.net.