ARS | Publication request: Organic blueberry production systems: management of plant nutrition, irrigation requirements, and weeds

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 14, 2012
Publication Date: June 18, 2013
Citation: Strik, B., Bryla, D.R., Vollmer, E., Sullivan, D. 2013. Organic blueberry production systems: management of plant nutrition, irrigation requirements, and weeds. Meeting Abstract. Meeting booklet.

Technical Abstract: A long-term systems trial was established to evaluate factorial management practices for organic production of highbush blueberry. The practices include: flat and raised planting beds; feather meal and fish emulsion fertilizer applied at 29 and 57 kg/ha N; sawdust mulch, compost topped with sawdust mulch, or weed mat; and two cultivars, 'Duke' and 'Liberty'. The planting was established in Oct. 2006 and was certified organic in 2008. From 2008-11, yield was 27% higher, on average, on raised beds than flat ground. Cumulative yield was also greater with feather meal than fish emulsion fertilizer in 'Duke', but similar regardless of source and rate of fertilizer applied in 'Liberty'. In contrast to feather meal, the higher rate of fish emulsion increased fruit firmness and soluble solids as well as leaf N in both cultivars, but reduced fruit weight. Weed mat was the best option for weed management, in terms of weed number and cost, while compost plus sawdust resulted in the most weeds and the highest weed-control cost; yield however was similar between the two treatments and higher in two out of three years than sawdust only. Soil temperature was as much as 4.5 C warmer under weed mat than under sawdust and up to 1 C warmer in raised beds than in flat ground; plants with these treatments required additional or more frequent irrigation to maintain the same soil water content as those on flat ground with sawdust mulch. So far, the best management systems for fruit production have been raised beds, feather meal or a low rate of fish emulsion fertilizer, and weed mat or compost plus sawdust mulch. Growth and yield of these treatments have been similar to conventional production systems.