What is GRODAN stone wool?

Basalt RocksIt is back to Nature. The raw material is basalt rocks and chalk. These are melted at 1600 C°. The lava is blown into a spinning chamber, which pulls the lava into fibers, much like ‘cotton candy’. When Mother Nature makes this wool we call it ‘angel hair’. If you have ever visited a volcano, you may have seen the fluffy angel hair flying around.

We pack the fibers together into a mat and cut GRODAN slabs & cubes from it. The stone wool Gro-Wool™ is bags with little flocks of 'angel hair'.


Important facts about GRODAN stone wool

GRODAN Stonewool

  • GRODAN stone wool was developed in Denmark in the early 1970's.The process makes excellent use of nature resources; We can produce 37 cu.ft. of wool from 1 cu. ft. of rocks.
  • Today we repurpose used GRODAN into bricks or other kinds of products. Even part of your new GRODAN is produced from recycled GRODAN.
  • GRODAN stone wool is the main reason that most of the world’s greenhouse vegetables are now grown hydroponically.
  • At full saturation, GRODAN holds approx 80% of its volume in water, leaving  20% of tiny air pockets. It is wrapped in UV-degradable plastic and the stone wool can be re-used in your garden to improve the aeration and water holding capacity.
  • GRODAN stone wool went into space on Challenger in 1986 and is still being used in NASA's testing with hydroponics.
  • You will also find GRODAN products at the EPCOT center / Walt Disney in Florida
  • You will find GRODAN stone wool in some garden centers and in virtually all hydroponics shops in North America