Green manure helps with the organic production of horticultural crops

A study published in the journal Biological Agriculture & Horticulture assessed soil nitrogen mineralization through field incubation and analyzed the rate of nitrogen release by commercial fertilizers compared with farmyard manure compost.

• For the study, a three-year organic crop rotation was set up in a field with sandy loam, with a cover crop of rye and vetch grown over the three autumn/winter seasons for green manure. Potato and lettuce were planted in the first year, followed by Swiss chard and turnips in the second year, and Portuguese cabbage and carrots in the third year.
• Nitrogen (N) mineralization was assessed by field incubation in response to green manure (GM), GM with 20 and 40 t ha-1 farmyard manure (FYM) compost (C20 and C40) and GM with 1 and 2 t ha-1 of commercial organic fertilizer (CF1 and CF2).
• The second season crops lettuce, turnip and carrot treated with C40 produced higher yields compared to all other treatments; most of the commercial fertilizer was mineralized during the previous crop.
• Swiss chard, grown in 54 days, produced higher yield for CF2 compared with C40.
• Continuous compost and GM application increased N availability and compost mineralized N recovery during longer growing season for the potatoes (124 days), and short growing season for cabbage (56 days).

The fast nitrogen release of commercial fertilizers increased the yield of the first crop of the year, whereas the slowly released nitrogen of farmyard manure compost increased the yield of both crops of the year, with a lower risk of soil nitrogen loss.

Learn more about eco-friendly crop production methods at GreenLivingNews.com.

Journal Reference:

Pinto R, Brito LM, Coutinho J. ORGANIC PRODUCTION OF HORTICULTURAL CROPS WITH GREEN MANURE, COMPOSTED FARMYARD MANURE AND ORGANIC FERTILISER. Biological Agriculture & Horticulture. 2017;33(4):269–284. DOI:10.1080/01448765.2017.1347521