This is because they are formed quite near the soil surface, the plant forming long thin roots that enlarge at intervals along their length to form the tubers. To harvest, you scrabble about in the soil until finding a root, you then gently pull upon it and, with luck, you will end up with a long length of root containing a number of swollen tubers, the effect being somewhat like a necklace. Another benefit of growing this plant is that it has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. Thus this is a very good companion plant in woodland and other integrated plantings.
Propagation is quite a simple matter.
Make sure you do not let them dry out as the tubers will quickly wither unless kept moist. Seed is also a simple matter. All Comments on web pages and plants. Back to PFAF Home Page.