Add potatoes, carrots, parsnips and turnip to slow cooker. Stir garlic into broth and pour over vegetables. Cover and cook on HIGH 4 hr. until vegetables are tender.
In small bowl or cup, whisk cream with flour until smooth. Mix in tarragon, thyme and salt. Stir mixture into liquid in slow cooker. Add green and wax beans. Cover and cook on HIGH an additional 15 min., or until beans are tender and sauce is thickened.
Substitute snow peas, sugar snap peas for green beans or wax beans. Remember when using a slow cooker, if you take the lid off the heat releases, so cooking time may need to be increased.