Dig a trench around the perimeter of the rhubarb plant, about 6 inches away from its crown. Dig down about 10 to 12 inches or to the depth of the root zone. Slide the shovel blade beneath the rhubarb roots and lift the entire plant out of the ground.
Loosen the soil on the roots and brush it off. Rinse the roots lightly to remove excess soil so you can see the roots, if necessary.
Break the root system into pieces the size of your fist, using a hatchet. Each piece must contain one or two growing buds, which are the narrow bumps at the top of the root section, and a piece of the root.
Spread 2 inches of compost over a well-drained garden site that receives six or more hours of daily sunlight. Incorporate the compost into the top 12 to 15 inches of soil by turning it with the shovel.
Plant each rhubarb division immediately into the prepared bed. Set the rhubarb divisions so the bud is at the top and 1 1/2 to 2 inches beneath the soil surface and with each division spaced 3 feet apart in all directions. Fill in the hole and firm the soil lightly. Water thoroughly so the root zone is moistened.