Take the lid off a 1-gallon plastic milk jug and discard it.
Cut the bottom of the milk jug off with a box cutter or scissors.
Place the bottomless, cap-less milk jug over your seedling in the garden.
Push a thin garden stake through the opening of the milk jug and into the soil to secure the jug to the ground.
Mound up the soil around the bottom edge of the jug slightly.
Leave the hot cap over the plant for 7 to 10 days.
Check on the plant under the hot cap regularly and remove the hot cap before the plant becomes crowded or if the weather gets hot.