Rick Durham, Consumer Horticulture Extension Specialist, University of Kentucky
 

Divide perennial to keep them healthy.

Are the perennials in your landscape in decline? Are they blooming less than they used to even though you fertilize and water them regularly? Is the foliage stunted and do the plants lack vigor? It may be that your plants have become too crowded and are in need of dividing. Most perennials need to be divided every 3-5 years, some even more often. Keeping plants growing vigorously by dividing them is one way to prevent problems with insects and disease. Vigorously growing plants are often able to tolerate or resist attack by pests. Digging and dividing perennials regularly would be a cultural practice in line with Integrated Pest Management, or IPM-an approach that allows homeowners to have a nice looking landscape using a minimum of pesticides.

Fall and spring are the times for dividing most perennials. As a general rule, perennials that bloom in the spring, such as daylilies, peonies, and bearded iris, should be divided in the fall. Perennials that bloom in the summer and fall, such as chrysanthemums, hostas, and asters, should be divided in the spring. The technique is pretty much the same regardless of the time of year. Dividing is best done as plants end their growth and begin dormancy in the fall or before regrowth occurs in the spring.

When digging perennials, loosen the soil around the plant with a shovel or garden fork to allow the plant to be lifted with a good portion of its roots system. Shake or work the root ball with your fingers to dislodge as much soil as possible. This will allow you to see the growing parts of the plant, newer growth is usually toward the outside of the clump. Next, pull or cut the clump apart leaving a mixture of old and new growth with each division. Trim back the foliage to 2-3 inches and remove any broken or excessively long roots. Plant the division at the same depth as it was previously growing. You will likely have extra plants so share or exchange some with neighbors or friends.

After planting, apply a layer of organic mulch and keep the plants well watered for several weeks until roots have become established. Fertilize the transplants only sparingly until growth resumes. Some plants will respond with increased bloom the following season, others may take a season or two to return to their full potential.

Select for fall color in trees before planting.

Will there be color on deciduous trees this fall? Betting on this is more certain than playing the lottery. Deciduous trees always exhibit some fall color as leaves lose their green chlorophyll. The degree of color depends on many factors including environmental conditions during the growing season and as time approaches for dormancy. Also, genetics of the particular tree is very important. Even under the best environmental conditions, tree leaves will only color to the extent that they are genetically capable of doing so. Since fall is the best time for planting trees and shrubs, why not take a look at the nursery in the next few weeks to select particular trees or cultivars of trees that exhibit good fall color. If you decide to plant some trees or shrubs this fall, here are a few helpful hint.

Fall is the best time to transplant trees and shrubs in Kentucky. Broad-leafed evergreens and conifers do best when planted in early fall while deciduous trees will do well if transplanted a little later in mid autumn. For most trees, select a site that is well drained. If your site is not well drained, consult with your local nursery professional or county agent for a recommendation of trees that will tolerate poorly drained sites. When digging the planting hole, remember that you want the hole to look more like a pie pan than a stew pot. Wide and shallow is preferred over narrow and deep. The plant should be transplanted to grow at the same depth in the soil as it was growing it its container or the nursery. Making the hole wide will help breakup up compacted soil and allow the tree's root system to more quickly become established. A minimum width for the planting hole would be two to three times the diameter of the tree's root ball, even wider is preferred if the soil is heavy or compacted. Back fill the hole with the same material removed from the hole. If higher quality soil or a peat/soil mixture is used for filling the hole, the tree's roots may become concentrated in this area and not expand out into the surrounding soil. Such a plant will be less drought tolerant and may be prone to blow over during heavy wind. Speaking of wind, staking of young tress is generally not recommended. Research has shown that movement of the tree's trunk after planting will stimulate more root growth than if the trunk is immobilized by staking and tying. Apply two to three inches of mulch after planting, but keep the mulch pulled away a few inches from the base of the tree. Even a few inches of mulch at the base of a tree can encourage disease problems by keeping the trunk too wet. Keep newly planted trees well watered until the ground freezes, and water again as the ground is allowed to thaw. No fertilizer should be applied during the first year of growth.
 

Fall Vegetable Garden Activities.

As crops finish in the vegetable garden, remember to remove plant residue to the compost pile. Repeated working of a garden with a tiller can produce a layer of compacted soil just below where the tines of the tiller reach. This compacted soil will interfere with air and water movement in the soil and may hinder root growth in the soil. To break up this compacted layer, try to plow the garden once a year, or once every other year at a minimum. If the garden is small such that plowing is impractical, use a shovel or garden fork to turn the soil and break up the compacted layer. If you plan to incorporate organic material such as compost or manure, this is a great time to do so. Spread the material over the surface of the garden before plowing so that the organic matter can be incorporated as plowing proceeds. This organic matter will also help reduce soil compaction problems. A soil test at this time of year will indicate whether lime is needed to raise the soil pH. If lime is needed, it can also be applied prior to plowing. For gardens on a sloped site, it will be beneficial to plant a cover crop of wheat or rye to reduce soil erosion. Otherwise, there is little need for addition working of the soil until spring.
 

Keep fresh tomatoes coming even after frost!

I was a little late getting my tomatoes planted this year and I still have lots of big, green fruit on the plants. Once it frosts, most of these fruit will turn to mush. Not to worry, while the plants and fruit are susceptible to frost, there is still a way to ensure fresh tomatoes well into autumn. Pick mature-sized green fruit, wrap them in newspaper, and store them in a cool dark place for a few weeks. After two to three weeks, unwrap a few of the fruit to see if any are ripening. Also check to make sure none are rotting. I have had "fresh" tomatoes for Thanksgiving or even later using this method. There not quite the same as vine-ripened, but not bad. As an alternative, I've been told that entire tomato plants with the fruit still attached can be cut from the garden and hung in a cool place where the fruit will slowly ripen. With either method, be sure to store the fruit in a cool place protected from freezing. Temperatures of 50-60 degrees should work well.
 

Other things to be doing as cool weather settles in.

Start cleaning things up in the garden and landscape:

• •After the first hard freeze, remove non-hardy annuals and cut back perennials to near ground level. The removed plant material can be placed in the compost bin.
• •Clean up around fruit trees by raking leaves and removing dried fruit. This will help control several diseases and insects.
• •Remove and burn bagworm cases from evergreens. The cases contain eggs which will hatch in spring to produce next year's population.
• •Check tree twigs for egg cases of eastern tent caterpillar. The egg cases are dark and shiny, they look like someone has dabbed laquer around the stem. They usually occur on branches that are about pencil size in diameter. They will break off the branch easily if rubbed with the hand or fingers.
• •Many insects can also be found in dead leaves in and around the garden and landscape. Getting rid of those dead tomato vines, bean bushes, and squash vines and fruit will lessen the chance that these pests will be able to overwinter in the garden and so will lessen the incidence of pest problems next spring.

• •Fall is the best time to apply fertilizer to woody plants. It is best to wait until the plants are dormant so don't apply fertilizer before late October. Dividing the fertilizer application into two or three parts is a good idea. Apply 1/3 in late October, 1/3 in November, and the final 1/3 in December. Altogether you should apply 2-3 pound of Nitrogen per 1000 square feet.
• •Don't forget to water trees and shrubs during fall and winter. Continue watering (in the absence of adequate rainfall) until the soil freezes. This is particularly true for evergreens since they continue to lose water through their leaves in winter. Keep the soil under your woody plants moist, not wet.
• •A layer of mulch applied at this time of year can have many beneficial effects in the home landscape. Mulch moderates the normal freeze/thaw cycle than can force many herbaceous perennial plants out of the ground. Mulch will also help conserve soil moisture and will serve as an insulating agent during severely cold temperatures.