Tricky to grow, blueberry bushes don't normally produce fruit for the first two years. Plant these bushes in acidic, sandy soil away from hills or woods, which often bring in colder air. The average growing season for blueberry bushes is 160 days. Frosts in late spring or early fall can damage the flowers and greatly reduce the fruit yield. This is why it is vital to cover your blueberry bush if temperatures drop to below 28 degrees F. Temperature below -20 degrees F will severely damage or kill the flower buds and branches.
Buy a sheet or frost cloth large enough to cover blueberry bushes all the way to the ground.
Place a thermometer by your bushes so you can monitor the temperature.
Gently drape the sheet or frost cloth over the blueberry bush. Make sure there are no gaps where heat can escape.
Uncover the blueberry bush during the day when the temperature has warmed up to over 28 degrees F.