Use of Composts in Grapes for Improving Vine Health – Soils
This project initiated a partnership between growers and university researchers to develop a compost based biological/organic system for grape production and disease management. The effectiveness of these composted organic materials are being evaluated for disease suppression and impacts on vine health and productivity by; monitoring vine nutritional status, juice quality, pruning weights, and monitoring the soil microbial population to record shifts in population levels of both beneficial and disease causing organisms. The goal in using compost is to provide growers with an environmentally safe and profitable alternative to pesticides to manage vineyard diseases in the soil, on fruit and foliage and have a positive influence on vine health and productivity, and will make it possible to grow new vines where soil diseases had previously kept vines from surviving. Application of compost also disposes of local organic residuals in a way that benefits urban and rural communities. Grower vineyard demonstration plots and the publication of compost application guidelines have and will be used to educate growers in the benefits of applying compost to grapevines.
Performance Target 1 – Experimental – Document the effectiveness of different types of compost to suppress fruit and root pathogens, and improve vine and soil health in grower’s vineyards.
Performance Target 2 – Educational – As a result of cooperating grower presentations at demonstration plot field days and the publication of compost application guidelines for vineyards, 50 additional growers will adopt the use of compost in their vineyards for disease suppression and to improve vine and soil health.
Milestones – Experimental, of the six milestones listed in the original proposal, five have been accomplished. The project was planned, vineyard plots were evaluated, and compost applied in cooperation with three growers who served as part of a core planning board. Measurements were collected through the first two growing seasons after application to determine the effectiveness of compost in suppressing grape diseases. Although it was noted in the original proposal that compost effects on the soil and plants will often take several years, the effectiveness of several types of compost to suppress fruit and root pathogens, and improve vine and soil health in grower’s and research vineyards were measured. Specific results to date are reported in the Outcomes and Appendices of this report.
Educational – Milestones, The first two milestones were accomplished in that the project was in constant review by the core grower group and the number of growers learning of the project and the potential for compost use in vineyards exceeded the original numbers (350 juice grape growers and 200 wine grape growers) proposed. Educational meetings and approximate numbers of growers present are listed in the appendix.
Satisfying part of milestone three, an article on compost use in vineyards was published by one of the growers (P. Roth) in the core group in the Wine East magazine which is widely distributed to growers in eastern United States. A compost application guideline for vineyards is being developed as an extension bulletin, which includes the methods and economic benefits to grape production. This publication will be distributed and discussed with growers at a March/April compost application in meetings. The last educational milestone states that 50 additional growers will adopt the use of compost in their vineyards for disease suppression and to improve vine and soil health. Grower interest in compost is very high. The numbers of growers currently utilizing compost in vineyards will be determined in February, March and April of 2003 during educational meetings and discussions.
Impacts and Contributions/Outcomes
Specific Results to Date:
Results after 19 months, indicate that compost is beginning to have a significant impact on soil microbial activity, which is one of the indicators of disease suppression in the soil (Figs. 1, 2 & 3; to obtain figures and other data associated with this project, contact the Northeast SARE office at 802/656-0471). A greenhouse study shows that compost incorporated in the soil will have an inhibiting effect on Cylindrocarpon destructans an important fungal pathogen of grape roots (Fig. 4). However, compost rate is important. Compost applied to the soil surface in the fall did reduce initial disease levels on grape foliage early in the season (Table 1 & 2). Several more seasons of evaluation are needed before reliable vineyard recommendations for compost use in vineyards to suppress diseases can be made.