Now that we’re getting ready to turn the calendar page from September to October, we can all breathe a collective sigh of relief. Cooler temps. Lower humidity. And so many other reasons to love fall! But a gardener’s work is never done. Let’s start by acknowledging that cold weather is coming. So make a plan to bring your houseplants back indoors. We’ve flirted with 40 degree temps already, and it won’t be long before cooler nights are the norm and not the exception. You should get ready by treating them for insect pests now. Clean them off with a gentle sprinkle and then pray with insecticide that is made for indoor plants. Safer’s Insecticidal Soap is a great choice and is very effective against soft-bodied pests. And following up with a systemic insecticide will keep any eggs or larvae from developing into new adult pests.
For many gardeners, Labor Day marked the end of summer and the beginning of the autumn lawn care season. Cooler temperatures and more regular rainfall make this an excellent time to start a new lawn or repair an existing one. The still-warm soil speeds up seed germination while the cooler air aids growth and development. The 30-day forecast for the Madison area isn’t predicting that temperatures will drop lower than the mid-50s until mid-October, so you have some time. But you’ll want to get your seed down soon to get the best results.
If your existing lawn is looking a little stressed, consider doing some aerating or de-thatching, followed by a late season fertilizer. This will stimulate root growth and help to lessen the problems that weaker, less vigorous lawns may develop over the winter months.
Fall is also great time for perennial weed control. The active ingredients can be more effective as the weeds go into dormancy and the actively growing grass will soon fill in the empty spaces. You may need a second application in late October for stubborn weeds like violets or chickweed, but it is best to wait until after the first frost to treat creeping charlie.
These golden mornings and evenings are perfect for strolling through your neighborhood to scout your friends’ fall perennial combinations. Consider planting aster, sedum or turtlehead in your own garden. Autumn is a great time to plant perennials. Just make sure to water them regularly and consider topping with a light mulch of marsh hay once the ground has frozen to prevent heaving.
Finish any transplanting or dividing of your perennials as soon as possible. You’ll want the plants to have plenty of time to re-establish before the ground freezes. And stop deadheading any plants that you want to develop seedpods for winter interest. Late summer and fall blooming perennials like coneflowers, and many of the perennial grasses look fabulous in the snowy garden, and as a bonus, provide food for birds in winter residence.
Stop fertilizing and deadheading your roses now to allow the rosehips to develop. The shorter days are a signal to begin dormancy and feeding them now will interfere with that process.
Plant any new evergreens as soon as possible. Evergreen plants don’t go completely dormant, and we like to give them as much time to establish new roots as possible. Using a root fertilizer, like Fertilome’s Root Stimulator is a great addition to any autumn planting. Commit to soaking the roots once a week until the ground freezes. In our area, that could be as late as mid-December.
Deciduous trees and shrubs can be planted into mid November. Again, watering is the key. Make a promise to your plants and don’t slack off. Adequate watering is the single, most important thing that you can do to ensure winter survival of establishing plants.
It’s too soon to do much pruning, as it may stimulate new growth that won’t be able to harden before winter. Wait until after Thanksgiving to prune deciduous trees and shrubs. Pruning evergreens is a job that should be put off until next June or July. Don’t despair though, we can think of plenty of other things for you to do!