Chinese Bugleweed (Lycopus lucidus)

Lycopus lucidus is known as Chinese bugleweed, ajekoshi, shirone, and di sun (地笋).  It is used in Chinese medicine, but there is very little information about its use as a vegetable.  The tubers are eaten boiled or preserved in salt in both China (Zhang 1991) and Japan (ASJ 1895).  They are crisp and juicy with very little flavor, sort of like water chestnut.  I don’t get the sense that is is a common vegetable in either place, based on the paucity of information, although it is possible that there is more information available in Chinese or Japanese sources that I cannot access.  It makes some of the largest tubers among the tuberous mints.  The plants are also very attractive with woody stems and glossy leaves, looking more ornamental than the other species listed here.  In a 9 month growing season, the plants reach about seven feet tall here.  I am attempting to cross it with native Lycopus species, but so far without success.  It should be hardy to at least USDA zone six.  It is fairly hardy and weedy and will come back every year without maintenance, although the plants do become crowded without thinning.  Tubers dehydrate and deteriorate quickly once dug.  I recommend keeping seed tubers in a plastic bag in the refrigerator and otherwise digging only as much as needed.