Late October to early November is the most effective time to control broadleaf weeds in lawns. Dandelions usually produce a flush of new plants in late September, and the winter annual weeds henbit and chickweed should have germinated in October. These young plants are small and easily controlled with herbicides such as 2,4-D or combination products (Trimec, Weed-B-Gon, Weed-Out) that contain 2,4-D, MCPP and Dicamba. Even established dandelions are more easily controlled now than in the spring because they are actively moving materials from the top portion of the plant to the roots in the fall. Herbicides will translocate to the roots as well and will kill the plant from the roots up.
Choose a day that is 50 degrees or higher. The better the weed is growing, the more weed killer will be moved from the leaves to the roots. Cold temperatures will slow this process but these products will still work at lower temperatures.
Weed Free Zone (also sold under the name of Speed Zone) contains the three active ingredients mentioned above, plus carfentrazone. It will give a quicker response than the other products mentioned especially as temperatures move below 50 degrees. (Ward Upham)
We normally recommend that Kentucky bluegrass and tall fescue be seeded in September but no later than October 15. Though plantings later than October 15 can be successful, the odds of success diminish as time passes.
The problem with late plantings is not that the seed will not come up or that young grass plants are sensitive to cold. Most often, the problem is with rooting. Unless the young grass plants have a fairly extensive root system, the freezing and thawing that takes place during winter heaves plants out of the ground, and they dry out and die.
Regardless of when planted, be sure the new lawn is kept watered through the fall. More mature lawns will need less frequent watering but all should go into the winter with moist soil. (Ward Upham)
If you are done mowing for the year, be sure to service your mower before putting it away. Make sure you drain the gas tank of gasoline-powered engines or use a gasoline stabilizer. Untreated gasoline can become thick and gummy. A few drops of oil squirted inside the spark plug hole (after you remove the spark plug) will help lubricate the cylinder. While you have the spark plug removed, replace it with a new one. If your equipment has a battery, clean the battery terminals, which usually corrode during the season. A wire-bristle brush is a good tool for doing this. The battery can then be removed or connected to a battery maintainer that will keep it charged over winter. If you remove the battery, be sure to store it in a protected location for the winter (a cool basement works best). Now is also an excellent time to sharpen mower blades so they'll be ready next spring.
Sharpening rotary mower blades is fairly straightforward. The following steps will guide you through this process:
* Check the blade for major damage. If you can't fix it, it likely will need to be replaced.
* Remove grass and debris from the blade with a moist cloth. Dry before beginning to sharpen the cutting edge.
* Remove nicks from the cutting edge, using a grinding wheel or hand-file.
* If using a grinding wheel, match the existing edge angle to the wheel. If hand-filing, file at the same angle as the existing edge.
* Grind or file until the edge is 1/32 inch, about the size of a period.
* Particularly with a grinding wheel, avoid overheating the blade as this may warp it.
* Clean the blade with solvent or oil, much like if you were cleaning a gun, for optimum winter storage. Avoid using water because it will promote rust.
Following these tips can help you better prepare your mower for winter storage and also save you some steps this coming spring. (Ward Upham)
Cool-season vegetables vary in cold tolerance, with some able to take colder temperatures than others. Semi-hardy crops can take a light frost but are damaged by temperatures in the mid- to upper-20s. Examples include beets, Chinese cabbage, collards, Irish potatoes, Bibb lettuce, mustard, radishes, spinach, Swiss chard, and leaf lettuce. Covering these plants when cold weather threatens can help extend the harvest season.
Plants termed “hardy” can take lower temperatures but are damaged when the temperature drops to the low 20s. These include cabbage, broccoli, cauliflower, Brussels sprouts, carrots, turnips, and kale.
Certain root crops can essentially be stored outside even after the leaves have been damaged or killed by frost. Beets, carrots, potatoes and turnips can be mulched and harvested as needed until the soil starts to freeze in late November to December.
Growing vegetables in Kansas can be a challenge, but we have an extremely long gardening season. We can harvest from early April (asparagus) to early December. Winter is a good time to plan and prepare for next year’s crops. (Ward Upham)
As winter approaches, we need to start thinking about storage of the bulbs that will not survive Kansas winters. The bulbs of gladiolus, caladium, dahlia, tuberous begonia, calla lily, and canna lily need to be dug and stored so they can be planted next year. Actually, the storage organ of the above plants is not a true bulb. Canna and calla lilies are rhizomes, caladium, and tuberous begonias are tubers, gladiolus is a corm, and dahlia is a tuberous rooted plant.
All of these plants should be dug after frost has at least partially browned the foliage. Then, allow them to dry for about a week in a shady, well-ventilated site such as a garage or tool shed. Freezing temperatures should be avoided. Remove any excess soil and pack them in peat moss, vermiculite, or perlite. Make sure the bulbs don’t touch so that if one decays, the rot doesn’t spread. Dusting them with fungicide before storage will help prevent them from rotting.
Caladium should be stored between 50 and 60 degrees F. The other bulbs mentioned should be stored as near 40 degrees F as possible. Finding a good spot to store the bulbs may be difficult. Some people place them against a basement wall farthest from the furnace and insulate them so the wall keeps them cool. (Ward Upham)
Pruning in August can stimulate new growth that is less hardy during the winter. But what about pruning at this time of year? Woody plants move sugars and other materials from the leaves to storage places in the woody portions of the plant just prior to leaf fall and we would like to maximize those stored energy reserves. Even pruning later in the fall can cause a problem by reducing the cold hardiness of woody plants. Dr. Rich Marini at Penn State Extension has written , “Based on everything that has been published we can conclude that woody plants do not attain maximum cold hardiness when they are pruned in the fall. Trees are affected more by heavy pruning than light pruning.” However, this does not mean that woody plants pruned in the fall will necessarily suffer winter damage. In most cases, I think you can get away with the old adage of “prune whenever your pruners are sharp.” However, damage can occur if we have a sharp drop in temperature before plants are completely hardened off. Also, marginally hardy plants are more susceptible to winter damage, especially if pruned in the fall. Though light pruning and removal of dead wood are fine this time of year, you may want to delay severe pruning until spring.
Consider pruning to be “light” if 10% of less of the plant is removed. Dead wood does not count in this calculation. Keep in mind that even light pruning of spring-blooming shrubs such as lilac and forsythia will reduce flowers for next year. We normally recommend that spring-bloomers be pruned after flowering.
Shrubs differ in how severely they can be cutback. Junipers do not break bud from within the plant and therefore should be trimmed lightly if you wish to keep the full shape. Overgrown junipers should be removed. On the other hand, there are certain shrubs that can be pruned back severely during the spring. Rejuvenation is the most severe type of pruning and may be used on multi-stem shrubs that have become too large with too many old branches to justify saving the younger canes. All stems are cut back to 3- to 5-inch stubs. This works well for spirea, forsythia, pyracantha, ninebark, Russian almond, sweet mock orange, shrub roses, and flowering quince. Just remember that spring is the correct time to do this, not now. (Ward Upham)
Iris are known for a couple of common problems: a fungus disease known as iris leaf spot and an insect named iris borer. Though both cause problems in the spring, now is the time to start control measures. Both the fungus and eggs of the borer overwinter on old, dead leaves. Remove dead leaves and cut back healthy leaves by ½ this fall to reduce populations of these pests. Also remove other garden debris from the iris bed. This can significantly cut down on problems next spring. (Ward Upham)
Though we often think of soil testing as a spring chore, fall can actually be a better time. Soil-testing laboratories are often very busy during the spring resulting in a longer turnaround from submission to recommendations. Also, soils in the spring are often waterlogged, making taking samples difficult. If your soil test suggests more organic matter, fall is a much better season because materials are more available than in the spring, and fresher materials can be used without harming young tender spring-planted plants.
Begin by taking a representative sample from at least six locations in the garden or lawn. Each sample should contain soil from the surface to about 6 to 8 inches deep. This is most easily done with a soil sampler. Many K-State Research and Extension offices have such samplers available for checkout. If you don’t have a sampler, use a shovel to dig straight down into the soil. Then shave a small layer off the back of the hole for your sample. Mix the samples together in a clean plastic container and select about 1 to 1.5 cups of soil. This can be placed in a plastic container such as a resealable plastic bag.
Take the soil to your county extension office to have tests done for a small charge at the K-State soil-testing laboratory. A soil test determines fertility problems, not other conditions that may exist such as poor drainage, poor soil structure, soil borne diseases or insects, chemical contaminants or damage, or shade with root competition from other plants. All of these conditions may reduce plant performance but cannot be evaluated by a soil test. (Ward Upham)
Ward Upham is the Kansas State Master Gardener Coordinator and runs the Horticulture Response Center. Other contributors include K-State Extension Specialists.