Dry edible beans are sensitive to damage at harvest. Beans are sold based on eye appeal so seed coat quality and colour are important. Producing beans that are clean, bright and whole is the ultimate goal and timely harvest is paramount to maintaining quality. Know the quality standards for the crop’s market class. The ideal moisture range for harvest is 16%–20%. Harvesting outside this range will reduce quality. Low moisture content at harvest will increase the amount of split seeds and cracked seed coats.
Weather conditions in the fall can cause some bean types to deteriorate in quality much more quickly than others. Some differences in classes are as follows:
- Kidney, Dutch brown and black beans tend to withstand more adverse weather at maturity than the white navy, cranberry, otebo and white kidney types.
- Cranberry beans are susceptible to darkening of seed coat following maturity, lowering their value, so prompt harvest is important.
- Larger seeded coloured beans tend to absorb more moisture after a rain, requiring more time to dry down.
- Adzuki beans are strongly upright, quite resistant to weathering and their hard seed coat resists absorption of moisture after maturity.
Each bean type has unique quality standards that buyers look for. It is important to know these prior to harvest. White beans must be clean and free of dirt tag (smearing) and staining. Seed size and colour are important in cranberry and adzuki beans, while a low level of cracked seed coats in kidney beans is an important quality factor.