2. Harden-off the seedlings.
Before you plant your pepper seedlings, you’ll need to harden them off by gradually exposing them to outdoor conditions. (This gradual exposure to the weather helps seedlings adjust, so they’ll be less stressed when you plant them. And less stress means bigger, more productive peppers.) When daytime temps reach the mid-60s, set the seedlings in a sheltered location outdoors, such as next to the house or garage, for a few hours each day for 3 or 4 days. Over the next week, slowly extend that outdoor time. Meanwhile, as the pepper seedlings are becoming accustomed to the outdoors, you can warm the pepper bed by covering it with dark landscape fabric.