The Jerusalem artichoke (Helianthus tuberosus L.), commonly called the sunchoke, grows to a height of 9 feet. A herbaceous perennial, the plant will continue to grow if only a small amount of tuberous root remains in the ground after harvest. The Jerusalem artichoke is commonly used in salads or for pickling, and has a flavor similar to a water chestnut. The tubers of the plant mature in the late summer and early fall. Most tubers attain a size of 4 inches long and 3 inches in diameter prior to harvesting.
Spread a layer of straw around the Jerusalem artichoke plants prior to the first hard freeze. The straw will help keep the soil from freezing too hard for cultivation in cold areas.
Harvest the Jerusalem artichoke after the first hard freeze kills the upper foliage of the plant. In areas with mild winters the tubers can be successfully harvested into the winter months.
Cut away the dead top growth of the plant prior to harvest. A lawn mower works well to remove the dead foliage, or cut it away using pruning lopers. Discard the dead foliage.
Rake the tubers up using a metal rake. For only one or two plants, use a shovel to dig up the tubers and lift them from the ground. The skin of the Jerusalem artichoke is thin, so be careful not to damage the tubers when harvesting. Take time to dig around the tubers, and lift them from the ground with care.
Store the Jerusalem artichokes immediately after harvest. Refrigerate them at 32° Fahrenheit. The vegetables store well if the relative humidity is maintained at 85 to 95 percent.