Why wait until cold arrives to decorate?
Warm fall days are great for installing Christmas lights, though most people do not think about installing them until after Thanksgiving. It is much easier to wrap branches with strings of lights on warm days in mid- to late October than on cold days in late November or early December.
The Botanic Garden staff starts installing strings of lights in early October.
Use LED lights to save on power and you will be able to use more strings on a circuit. Buy warm-color white LED lights if you want to match the color of the commonly used white incandescent lights. Cool-color LED white lights have a blue cast to them.
Wrap branches of your trees with strings of lights to accent the tree's form.
You may be able to leave lights on your trees for a couple of years to save time. I have had problems with squirrels chewing through the strings of lights left in trees, so it is a good idea to monitor them over the summer and remove them if you start seeing damage.
As the tree grows, the strings of lights will tighten, so they will need to be reinstalled. Be sure to use power cords that are rated for outdoor use.
• The average first frost at the Chicago Botanic Garden is Oct. 15, though it is typically later in Chicago. Tender plants can be protected from light freezes by covering them with sheets, plastic or boxes.
When nighttime temperatures begin dropping below 40 degrees, it is time to bring in any tropical plants you keep outside. A gradual decline in temperatures over a period of time is best, as the plants will acclimate some to the cooling weather.
You may want to move the tropical plants in for a night if there has been a long spell of warm weather and a sudden dramatic drop in temperature is predicted.
• Be aware of the weather as you spray to control weeds late in the fall. Herbicides are most effective when temperatures are consistently above 55 degrees and weeds are actively growing. Spot spray the weeds to minimize the amount of herbicide you use.
• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.