How Late Can You Plant in Fall/Winter in Atlanta?

Q: I have a major landscaping project this fall. How late can I plant in Atlanta before soil gets too cold for root growth?

A: No hard rule. Roots in cold soil grow less than in warm soil, but more than if held above ground. Evergreens need winter water because leaves lose moisture on windy days; a small root system struggles. Water occasionally, and evergreens can survive and flourish in spring. Deciduous plants are less demanding without leaves. It's worth the gamble to install plants in winter and regularly water near trunks to keep root balls moist until spring.