This is a professional grower grade Calcium Soil Conditioner fertilizer, as used by myself. It can be used on brassica plants , potatoes and other vegetables . At the rate of 30/60 g per sq meter. One application will last all season. It will increase microbial and earth worm activity , contains calcified seaweed which will neutralise surface acidity as it acts a a liming agent. Also provides trace elements which will activate soil microbes and improves soil structure and breaks down organic matter. I have repacked into smaller lots for the gardener into recycled plastic storage containers. So after you have used the ferttilzer you have a nice used sturdy storage box with lid . I am selling this product by volume but weight is approx 4.5 kg.