Organic strawberries grown on organic mulch: impact of nitrogen fertilization strategies on crop yields and profitability

Description

Summer strawberries grown on plastic mulch start producing fruit in the year the strawberries are planted and continue throughout each season. The plastic mulch also controls weeds.

Since strawberry plants are in the ground for two years, it is often impossible to provide all the nitrogen they need solely by applying compost at planting without putting on too much phosphorus. So organic growers must use cultural practices that supply nitrogen as well as adding compost before unrolling the plastic. Fertilizer is then added with a drip system (fertigation) started in late June. In the second year of production, as it is not possible to incorporate fertilizer into the soil, nutrients are supplied entirely by fertigation.

There is a range of soluble organic fertilizers on the market: BioFert Tomato and Vegetable 3-1-4, BioFert Cal-O 6% Calcium, and Trident (6-1-1), a new, less costly product. Various strategies will be tested and their total costs calculated.

For organic summer strawberries grown on plastic, one of the most expensive items compared to conventional production is the cost of nitrogen in a form that is acceptable under organic standards. This limits the production of not only organic summer strawberries, but also high-density fruit and vegetable crops, where planting is costly.

Objective(s)

• Test cost-effective organic fertilization strategies for summer strawberries on plastic
• Assess the profitability of crops with high planting costs due to the use of plastic mulch