08/28/2026
**SEPTEMBER Garden Checklist **
Here are a few research-based jobs to tackle this month:
--> Keep harvesting. Pick tomatoes, peppers, squash and other warm-season vegetables regularly. Keep an eye on nighttime temperatures as we move closer to our first fall frost.
--> Give cool-season crops some attention. Lettuce, spinach, radishes and other cool-season vegetables appreciate September's cooler temperatures. Protect tender crops when frost threatens.
--> Plant trees and shrubs. Early fall is an excellent planting window in Idaho. With shoot growth slowing, plants can put energy into establishing roots before winter.
--> Give your lawn some fall TLC. Late summer and fall are the preferred times to seed cool-season Idaho lawns. Fall is also a good time for core aeration and appropriate fertilization as turf begins storing energy in its roots for winter.
--> Adjust your watering. Don't automatically keep using your July irrigation schedule. As temperatures cool, landscapes generally require less water. Continue monitoring soil moisture and gradually adjust irrigation to actual plant needs.
---> Start cleaning—but don't overdo it. Remove diseased vegetable plants and heavily infested plant material. Healthy garden debris and fallen leaves can become valuable additions to a properly managed compost pile.
-->Take garden notes! What varieties performed well? What struggled? Where did you have insect, disease or irrigation problems? A few notes now can make planning next year's garden much easier.
September Garden Tip:
Fall isn't the end of the gardening season—it's the beginning of preparing for a healthier garden next year.
Questions about your garden, lawn, or landscape? Contact University of Idaho Extension, Payette County for research-based horticulture information.
University of Idaho Extension — Bringing research-based information to Idaho communities.
