Dr. Hulda Clark’s Herbal Kidney Cleanse This herbal kidney cleanse is taken from Dr. Hulda Clark’s book "The Cure for All Advanced Cancers," page 560. Dr. Huld Clark First Preparation | Ingredients: root o Half a cup dried hydrangea root (Hydrangea arborescens) o Half a cup gravel root (Eupatorium purpureum) o Half a cup marshmallow root (Althea officinallis) o Black Cherr..