Rootknot nematodes can infest ginseng roots and reduce their value or destroy the marketability of the crop. Insects like aphids, leafhoppers, lygus bugs, slugs, and white grubs also must be controlled. The time of harvesting depends on the method of propagation used. Ginseng roots are ready to harvest in four to nine years when planted from seed and in two to four years when transplants are set. Average ginseng roots are about four inches long, one inch thick below the crown, forked, and average one ounce each, when fresh.
Older roots weigh the most and bring the highest prices when properly cured.
Digging of the profitable ginseng roots should be done with care. The roots should be removed from the soil with their forks intact. Adhering soil should be removed carefully, without scraping or scrubbing. Some growers replant young and undersized roots or heel them in until spring planting. After they have been dug up and cleaned, the roots should be dried in a heated, well-ventilated room.