ABSTRACT
Lowbush blueberry (Vaccinium angustifolium Ait.) growers have relied primarily on the management of existing fields after clearing of forest land to encourage development of natural stands. A management practice unique to lowbush blueberry production is pruning above ground stems by fire or flail mowing to stimulate vigorous stem growth from rhizomes the following season. This practice results in an alternate year production cycle. Lowbush blueberry fields are managed on a two-year cycle with herbicide and fertilizer applications usually applied before shoots emerge from rhizomes the first year of the production cycle. Throop and Hanson (1997) reported that absorption of fertilizer-derived N was greatest for highbush blueberry plants from late bloom (May) until after fruit harvest (mid-August). An increase in absorption efficiency with increased growth rates was also reported in plum (Weinbaum et al., 1978) and grape (Conradie, 1986). Previous studies on lowbush blueberry suggest that date of fertilizer application may be more important on sandy textured than on heavier soils (Smagula and Litten, 2001). In this study, we determined the effect of time of fertilizer
application on nutrient uptake, soil nutrient availability, plant growth, and yield as related to stage of plant development in the prune year.
