Blue Lupins are a cheap and quick way to suppress weeds and replace lost nutrients, especially nitrogen, in soil. Plant in autumn to grow through winter and mulch back into the soil in late winter/early spring. Blue Lupins has a similar effect to mulch on soil; it improves soil structure, fertility and micro-organism activity. Once dug back into the soil, the broken down organic matter helps to provide optimal soil conditions for spring planting. For optimum results sow lupin and mustard seed together. Apply at a rate of three parts lupin to one part mustard.