Three Major Advantages of Using Rockwool For Hydroponic Gardening

Rockwool is a type of mineral fiber typically used in housing insulation. Hydroponic growers, however, have discovered that it also acts as a fantastic medium for soil less growing. First developed in Demark in the 1970´s, hydroponic growers have used this medium to grow a large variety of plants with great success. Here are a few reasons rockwool is one of the most popular media used today.

Retains Water - One of the great advantages of hydroponics, growing plants without soil, is also one of its greatest weaknesses. With all the drawbacks that come with traditional soil gardening, soil is able to retain moisture extremely well, which is why many houseplants are able to survive infrequent waterings. Rockwool, can hold moisture just as well, giving hydroponic gardeners a greater margin of error. If a hydroponic gardener should incorrectly time waterings or should the timer fail because of a power outage, the damage done to a plant in rockwool will be minimal, whereas the same situation might devastating to plants in another medium. Rockwool blocks are also often wrapped in plastic, which helps them retain moisture even more and thus reduce evaporation.

Holds Oxygen - Your roots need oxygen in order to survive and process nutrients as well. Insufficient oxygen to the roots can slow C02 assimilation in the vegetative part of the plant, which would slow photosynthesis and carbohydrate production. Since rockwool is very porous, roots almost always have access to all of the oxygen they need. This allows gardeners more room for error because it makes it more difficult to overwater your hydroponically grown plants.

Versatility - Rockwool is suitable for almost every kind of plant that you can grow hydroponically at any stage of development. Whether you are in the process of germinating seeds or tending to an older plant transplanted from your soil garden, rockwool can accommodate your needs. In fact, rockwool is usually provided in several different shapes and sizes to suit various growers such as:

Miniblocks - Miniblocks, also often called "starter cubes" are very small blocks of rockwool. These are ideal for germinating your seeds or propagating through cutting. These often have the added feature of plastic wrapped around the cube to hold in moisture.

Full Sized blocks - These are designed to accommodate larger plants. To make it easier to transfer starter blocks to full sized blocks, the larger blocks will have a one inch cubed hole in the center of the block. Once the seed on the starter block has successfully germinated or the cutting has successfully taken root, you can simply place your starter block inside the full sized block

Slabs – Slabs are usually three feet long and come in a variety of widths. They are typically used for vegetable cropping.

Loose rockwool - If you have circular pots that you want to fill with a medium, you can use loose, or granulated rockwool. These can also be combined with another medium to get the maximum benefits of two different media.

Good luck!