Determining the nitrogen contribution of mulch mineralization in highbush blueberry cultivation so that nitrogen fertilizer applications meet crop requirements more effectively

Description

In highbush blueberry production, mulch is spread around the base of the plants to suppress weed growth. Some mulches may release nitrogen as they decompose, while others, including fresh sawdust mulch, require the addition of nitrogen fertilizer because soil bacteria mobilize nitrogen to decompose this mulch, given its elevated C/N content. While aged sawdust mulch may supply nitrogen, this contribution has not yet been quantified.

Since the current body of information was generated outside Québec, it is necessary to conduct studies under our own climate conditions. We therefore selected two study sites, one in Montérégie and the other in Chaudière-Appalaches, which will receive no mulch, fresh mulch, and aged mulch blended with four nitrogen doses (0, 30, 60, and 90 kg N/ha). Lastly, this study will determine the nitrogen contribution of mulch mineralization in highbush blueberry cultivation so that mineral nitrogen fertilizer applications can be better tailored to actual crop requirements.

Objective(s)

• Characterize the nitrogen contribution of sawdust mulch.
• Survey the literature on the nitrogen requirements of highbush blueberries that maintenance fertilizer applications must satisfy.