Whether it is early spring and you need to protect tender annuals from an unexpected frost or it is autumn and the growing season is winding down, there are often times when a gardener must protect flowers from frosts. As long as you anticipate the frost on the night before, you can successfully cover your flowers with a thin plastic sheet held up by wooden stakes.
Drive a wooden stake into the ground near every flower growing in the ground that needs protection. Drive the stakes approximately 3 inches into the soil. The stakes will support the plastic above the flowers.
Make small tents over the individual plants by placing the plastic sheeting over each stake. Center the plastic over the stakes and extend the sheeting down to the soil around the plant. Secure the plastic on the ground with bricks or large rocks.
Create large tents over larger growing areas to cover groups of tender plants. Place the plastic sheeting over the stakes that are next to each plant so the stakes will hold the plastic sheeting up. Extend the ends of the sheeting down to the soil around the edges of the growing area and secure the sheeting on the ground with the bricks or large rocks.
Remove the plastic sheeting the next morning after the sun rises and the temperature moderates.