Western Mountains and High Plains
If you have time and space allotted, now is a good time to plant a fall crop of spinach. You will be harvesting the tender, succulent leaves for salads in fall. If you like, overwinter the young plants with mulch for an early crop of spring greens.
Once the tops of 80 percent of your onion plants have fallen over, it's time to harvest the bulbs. Shake away excess soil from the bulbs and dry for a few days on a screen in the sun. Then you can clean loose skins and store in mesh bags.
Fertilize Cool-Season Lawns
As Labor Day approaches, it's time to make plans to fertilize your bluegrass, fescue, or perennial ryegrass lawn. Cool-season grasses make the most out of fertilizer applications in the fall. Use 1 pound of actual nitrogen per 1,000 square feet.
Cut Back on Watering Trees
As the days get shorter and evenings cool down, it's time to reduce watering of trees, shrubs, and other woody plants in the landscape. These plants need to prepare for dormancy and will not benefit from too much water. Water periodically when the soil is dry if rainfall is less than usual.
Replant Spring Bulbs
If you have areas where spring-flowering bulbs need to be divided or just relocated for more sunlight, move them now. Hopefully you have marked their locations so you can safely lift them out with a spading fork. Prepare the new location with compost and add some bulb fertilizer.