Multigrow rockwool – Sustainable rockwool for flowers and vegetable Growers. A unique point of Multigrow rockwool is that it contains an all-natural binder (ECOSE®). ECOSE® Technology is a revolutionary, new, formaldehyde-free binder technology, based on rapidly renewable materials instead of petro-based chemicals. It reduces embodied energy and delivers superior environmental sustainability. Multigrow rockwool is sterile and therefore free of diseases, insects and weeds. Multigrow rockwool has an optimal balance of water holding capacity and porosity which leads to healthy, fast-growing plants!