Follow our September gardening checklist for North Shore and Chicagoland gardens, including fall planting, pruning, lawn care, watering, and winter prep.

Learn when and how to plant tulips, daffodils, hyacinths, and crocuses for beautiful spring color in North Shore and Chicagoland gardens.

Watering: In hotter temperatures, water your garden frequently to keep plants happy. If no rain, water twice a week. Aim for 1 inch of rain per week at 75°F, plus 1/2 inch for every 10 degrees above. (Ex. For 85°F, aim for 1.5" of rainfall. A good sprinkler is essential.) Especially Water Evergreens: If rainfall is scarce be sure to keep evergreen trees and shrubs hydrated. Because plants such as yew and arborvitae never go completely dormant, their roots should be slightly moist to help the plant survive drying winter winds.If you start watering evergreens now they will have plenty of soil moisture around their roots before freezing temperatures make irrigation impossible. Newly planted evergreens are particularly susceptible to dry soil so make sure they get at least an inch of water a week. Soaker hoses are a great way to irrigate newly planted evergreens. The hose allows water to seeps slowly into the soil so there is no wasteful runoff and less evaporative water loss. Last Fertilizer Application: Stop feeding roses, trees, shrubs, and perennial flowers after the 15th of August. Feeding your plants too late in summer and fall encourages new growth that probably won’t survive the winter. Allow the perennials and shrubs to toughen up for 6-8 weeks before the first freezing temperatures hit. (But, definitely make that last application of fertilizer for the season before the 15th, especially if it has been 4 weeks since the last time that you fertilized!) Welcome Hummingbirds to your garden as they migrate South: Add additional Salvia and other tubular shaped flowering plants to your gardens. These are some of their favorites: Lantana, Salvia, Cardinal Flower (Lobelia), Trumpet Vine, Columbine, Phlox, Beebalm, Penstemon, Coral Honeysuckle, Rhododendron Wage War on Weeds: If you’ve been putting off weeding chores in the garden, August is the time to finally get busy. That’s because, as the growing season winds down, both annual and perennial weeds start to produce thousands of seeds that will germinate in your garden next spring. If left unchecked, these pesky invaders become extremely difficult to eliminate. The best time to weed is right after a rain when the soil is still moist. If rainfall is scarce, irrigate your garden thoroughly the night before you start your attack. You can pull weeds by hand or use a hoe. Just be sure to remove the roots. Weeds such as crabgrass or purslane quickly regenerate from any root left in the soil. As soon as you have the weeds removed, cover the area with a thick mulch of compost, leaves, or shredded bark. Plant Perennials and Shrubs: Late summer is a perfect time to plant perennials and flowering shrubs in many areas. They’ll take root during the cool, moist fall weather and be ready to bloom next spring and summer. Some good candidates to plant now include hydrangeas, daylilies, lilies, sedums, ornamental grasses, peonies and bearded iris. Just be sure you keep your new plants well watered if the weather is hot and dry. Mulching the beds also helps preserve soil moisture.   Divide Perennial Plants: August is the best time to dig and divide perennial flowers in your garden (such as hosta, Oriental poppy, lily, daylily, ornamental grasses, and bearded iris). Use a spade to lift the plant from the ground being careful to damage the root ball as little as possible. When the clump is out of the ground, use a large garden knife or spade to cut it into smaller pieces. Then, replant the smaller pieces or divisions as soon as possible. Some perennial flowers such as bearded iris and ornamental grasses have a tendency to die out in the center. When you divide these perennials cut around the centers and toss the dead tissue on your compost pile. Replace Annual Flowers: By late summer, some annual flowers may look a bit worn out. Give your pots and planters a makeover by tucking in fresh, ready-to-bloom cool-season annual flowers that will keep the color show going through the fall. Just gently pull out dead or dying annuals, mix in a bit of fresh soil, and drop in the replacement. It’s that easy! Natives: Continue adding native plants to your garden when filling open spaces. Natives and local fauna (insects, birds and animals) developed relying on each other for hundreds of years. Even adding just a few native plants to your yard will attract more native birds, animals and pollinators. Shop our native plants here. Insects: Insects are still in our gardens– good and bad! Inspect your plants for signs of pest damage and treat them accordingly. Using systemic products that last for 30 days in the leaves that are sprayed; are more Earth-Friendly because they are not sprayed as frequently killing beneficial insects. Spraying at dusk is the most Earth-friendly time to apply them; as the pollinators are back at their hives at dusk.    BioAdvanced® | Dual Action Rose & Flower Insect Killer BioAdvanced® | 3-in-1 Insect, Disease & Mite Control Ready to Spray with Hose End Sprayer BioAdvanced® | 3-in-1 Insect, Disease, & Mite Control Ready to Use with Trigger Sprayer Grub Control: It is not too late for it, even if you missed the curative application of GrubEx in April. Its relative solubility and stability in the soil are suited for extended soil residual that remains in the grub zone, especially for applications made between egg hatch (mid-July) and the second instar life stage (when grubs are less than half their adult size). For optimum curative control: (1.) Avoid mowing the lawn until the treated area has been irrigated to allow for maximum, uniform uptake into the grass plants (2.) Water-in the application within 7 day of application Repot Houseplants: If you’ve given your houseplants a summer vacation outdoors, chances are they responded by with a lot of new growth. If so, August is the perfect time to move them to a larger container with fresh potting mix. This gives the plants time to acclimate to their new pots before cool weather arrives in fall. One of the best ways to know if your plant is ready for transplanting is to check the drainage hole of the pot. If you find roots dangling out of the drainage hole it means your plant is becoming too large for its container. Select a new pot that’s slightly larger than the old one by only 2-4 inches in diameter. Always keep the top of the root area 1 inch from the top edge of the pot – remember roots grow down and out from the original root ball, never up; so never put fresh potting mix on top of the root ball. Harvest Herbs: Although herbs can be harvested throughout the summer, the oils responsible for the most intense flavor and aroma are at their peak in late summer, just before the plants flower. Clip foliage in the early morning after the dew dries, but before the day heats up. One of the easiest ways to store herbs is to rinse them under cold water, chop them coarsely, and place them in water-filled ice cube trays. Then, simply place the trays in the freezer and pop out frozen herbs as you need them.