Remove dense leaf litter on turf grass and in flower beds. Cool season fescue lawns develop strong roots during autumn months. Turf growth (above and below ground level) depends upon adequate light and moisture. A heavy layer of leaves blocks both of these growth essentials. Years ago my neighbor proved that point. On advice in a magazine, he used a mulching mower to shred leaves and left them in place to add nutrients to his lawn. (This is practical only with a very light layer of fallen leaves.) My neighbor’s grass had lots of dead patches come spring because the covering of chopped leaves was too thick. After clearing old plant stalks and leaves from my vegetable and flower beds, I do advocate mulching with composted leaves from the prior autumn. Shredded tree leaves left to decompose for 10 to 12 months in my woods create humus with a fine, crumbly consistency. No need to “work” this organic material into soil. It enriches your garden from the top down.
Container-grown perennials can be transplanted during the cold season. When there are lots of chilly days start on a warmer/sunny day and do other steps on later dates whenever weather is mild during autumn, winter or early spring. Select the planting site. On your shopping trip be sure to buy a landscape plant whose mature size as well as soil, sunshine and moisture needs are suited to that location. When purchasing trees or shrubs avoid those with broken branches or a poor shape. Do not buy nursery stock with cuts or scrapes on the stems/trunk. Trees and shrubs with stem injuries rarely have a long life expectancy. Bacteria and fungal spores enter where bark is damaged. Plant diseases develop. Borers and other harmful insects seem to target trees with trunk injuries.
Dig the planting hole. (It and the soil mound can be covered with a tarp if the plant is to be set out another day.) One of the oldest bits of advice for transplanting trees is “Don’t dig a $2 hole for a $10 tree.” That’s true for width. Three to five times the width of the rootball is good for a planting hole. What many homeowners don’t realize is that deeper is NOT better. Planting too deep is one of the most common mistakes made when installing woody ornamentals.
A tree trunk naturally widens at the base where the roots start. This is called the trunk flare. Trees grown at the proper depth in a nursery will have a visible flare where the trunk ends and the rootball begins. With a containerized tree stand a yardstick next to the container to measure from the bottom up to the trunk flare. Make the hole about two inches less deep than that measurement. This ensures the flare will remain above the soil surface after settling takes place. Those who have heavy (clay) soil have the greatest tendency to go narrow and deep. Remember you aren’t digging a post hole. The sides of a hole dug in clay often are shiny and hard.
Roots have difficulty penetrating glazed sides and rainwater runs into the disturbed soil around the rootball but does not drain out. Avoid this scenario. Where native soil is heavy, set the woody plant even higher (three or four inches less deep than the rootball measurement). Make the hole four times as wide. Score the sides. Cuts in the soil walls allow both water and roots to move beyond the planting hole. Research has shown adding peat moss or other organic materials and fertilizer to native soil before putting it back into the hole around the roots of woody transplants is not a good thing. Tree experts say break up clods, then backfill the hole with the same soil that was removed. Use no fertilizer during the first year after installation. Allowing grass to grow close to trees leads to injuries from weed-whackers and lawn mowers. That damage can be fatal. Use mulch to keep a three-foot or larger area around the base of woody ornamentals free of grass and weeds. Don’t pile soil or mulch up on tree trunks. That holds moisture causing rot and/or allows rodents to tunnel unseen under the mulch and weaken or kill the plant by gnawing on the bark.
This is the final column for 2014. Plateau Gardening articles for 2015 start in February.
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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 (931-484-6743) for answers to horticulture questions, free publications and to learn about the Master Gardener program. Send email comments or yard and garden inquiries to Master Gardener Rae (MGardenerRae@frontiernet.net).