Grant: Engage Grants Program

Boates Farm is an organic apple producer in Woodville, NS and has been struggling for adequate nitrogen (N) nutrition and proper tree growth for the orchard. Nitrogen nutrition can be achieved easily with relatively low cost in conventional apple production using synthetic fertilizers. However, this is not the case in organic systems where growers mostly rely on compost and other organic fertilizers which are often complicated by their slow and somewhat unpredictable mineralization. Therefore, improving N use efficiency and providing N at a precise time is quite important but challenging in organic systems including Boates Farm. The Swiss sandwich system is a new concept for better N management of tree fruits, especially organic apples, and is gaining popularity. In this system, a strip of mainly legume ground cover is planted in the tree trunk line with bare ground strips on both sides. Biomass from the legume is incorporated into the bare strips. It is not advisable to grow more than 1-1.5 m legume strips in a new orchard. Alternatively, growing legume covers in the lane ways can offer two to three times more area than the trunk line for the cover crops and thus the outcome will ensure more biomass and N addition for the bare strips. The objectives of this study are to examine the impacts of modified Swiss sandwich system of ground cover management on soil N supply, tree performance and fruit quality. Additional objective will be to develop a management tool to increase soil quality and tree nutrition best suited for the grower's condition. In this modified Swiss sandwich system, 1.0 m bare ground strips will be tilled on both sides of the tree line to provide a competition-free zone for tree roots. Cover crops will be grown in the lane way of ~3.5 m width. Bare strips will receive 2000 kg/ha Nutriwave as starter fertilizer. Plots will consist of a row three study trees with one guard tree on each side in a RCB design with four replications. Ground cover species will be mowed as necessary and their biomass will be incorporated into the bare strips. Nitrogen contents of the cover crops will be analysed before each mowing. Soil and leaf samples will be collected and analysed for N contents. Tree growth and fruit quality parameters