Two weeks after last frost date in your region. Transplant smaller plants to pots and bring inside. Don't plant where soil has been recently limed.
Peppers require full sun, but can be shaded during the heat of day to protect against sunscald.
They need a long season to ripen, so choose an early variety if you garden in the north. Make a cutworm collar by cutting an empty toilet paper roll in half and placing around plant carefully. Press into soil so that half is below ground. Provide slug protection if necessary. A spray of a small spoonful of epsom salts in water is a good idea if your soil is deficient in magnesium.