Newer trees need care in autumn months

Gardens are starting to dry out again after the recent rains, so you should provide supplemental water as needed to new plants installed this year and during the last two to three years. Wilting leaves and foliage that are an off-color green are signs that a plant is under drought stress.

Evergreens that are an off-color or that are shedding needles on the inside of the plant should also be checked to see if they are dry. Early onset of fall color is also a sign of stress.

Newly planted evergreens are particularly important to keep watered so that they do not go into winter dry. Evergreens continue to lose water through their leaves during winter and are more likely to sustain winter burn if they are dry as they go into the winter season. Densely branched evergreens that have been recently watered are best watered at the base of the plants.

• It's a good idea to make note at this time of any changes you have thought about making to your garden next year. Digital photos will also be helpful to continue planning over winter and help you next spring recall current garden conditions. It is easy to forget these observations over winter. Good garden notes will make you a more efficient and focused gardener next year and help you attain the goals you have for your garden.

• There is still time to fertilize your lawn to improve the color and vigor of the grass if you have not done so yet and if your lawn needs a boost. If you have been using a recycling mower and are not collecting the grass clippings, then the amount of supplemental fertilizer you need will likely be reduced. So it's best not to fertilize just because it's time to do so.

Nitrogen is the nutrient required the most, although too much nitrogen can cause excessive top growth and disease problems. In most cases, a rate of one pound of nitrogen per 1,000 square feet of lawn is adequate.

Many soils in the Chicago area have adequate levels of phosphorus so it is probably not needed for your lawn.

• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.