Author
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Black, Brent |
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Submitted to: Blueberry Research Extension North American Workers Conference Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 8/19/2002 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Highbush blueberry is adapted to low-pH well-drained sandy soils, which limits the number of suitable sites for commercial production. For small-scale production on sites considered unsuitable for highbush blueberry, we have tested available by-products as constituents in soil-less media. By-products included bottom ash from a coal-fired power plant, composted biosolids (sewage sludge), and leaf compost from a residential recycling program. Results from the first phase of this research were recently reported. Based on these results, a second study was established to test additional sources of compost, to determine the optimal ash : compost ratio, and the relative adaptability of three cultivars to this system. Sources included commercially available composts of biosolids, yard waste, and a crab and poultry waste mixture, and a barnyard compost obtained from an experimental facility. The biosolid compost was combined with bottom ash at rates of 20, 40, 60 and 80 percent, v/v. The remaining composts were each mixed with coal ash at rates of 40 percent compost, v/v. The pH and buffering capacity of the resulting mixes were determined and sulfur was added for a target pH of 4.5. In the spring of 2000, one-year-old tissue-cultured plants of 'Bluecrop', 'Duke', and 'Sierra' were obtained from a commercial nursery and planted in 3.78 dm3 containers of sulfur-amended treatment mixes. Control treatments were Berryland sand collected from a blueberry farm in New Jersey. Six replicate plants were established for each cultivar-treatment mix combination. Plants showed rapid growth during the 2000 season and set some fruit in 2001. Treatment means for 2001 yield ranged from 10 to 368 grams per plant. Plants height, spread and canopy volume were determined after growth cessation in the autumn of 2001. Plants growing on ash-compost mixes showed greater early growth and yields than on Berryland sand, with the optimal ash:compost ratio between 40 percent and 60 percent compost, v/v. Yield data for 2002 will also be presented. |
