Yes, normally if you have registration on your car then most all states require you to continue insurance coverage on the vehicle, even if you are not driving it.

If you do not want to insure a car and it is off the public roadways then check with your state what steps to take. Usually it will include turning in your license plates and registration on the vehicle. If this is done then normally you can take insurance off of the vehicle without receiving penalties.

To find out what your state's laws are regarding this contact your Department of Motor Vehicles.