This will depend on a range of factors including the type of compost you use, your vineyard location, climate and soil type and your type of irrigation. As a general rule, you can expect your compost to deliver significant amounts of potassium initially, with a slower release of nutrients such as nitrogen and phosphorous over time. A nutrient calculator is available to help you predict the nutrient supply from compost. It’s a good idea to monitor your soil and plants so that you can adjust your fertiliser applications if necessary.