How hydroponics root holding media (I think called) plugs are made?

Question

Materials and how they are held together.

Answer 1

The different media is made in pads that are easily split up when the plants are sufficently large enough to go to the main growing area. The pads I have frequently used come in a number of linked cube sizes depending on the plant one is growing. 1 inch by 1 inch squares to about 2 inch by 2 inch squares for primary seeding or to root cuttings. The whole pad is sized to fit industry standard trays that allow for easy movement as once they are saturated it's like trying to move wet burlap or cardboard, heavy and no support so that without the tray, they fall apart from their weight and damage the new seedlings. I always have a sloped seed pad sprouting table to start the hundreds of new plants (almost daily in rotation). It is kept moist from a continuous flow of nutrient solution. When plants are ready, the pads are broken down carefully into the individual plants and tranfered to the main growing area. Some crops do well to start in the small pad cubes but then go to a larger 4 inch by 4 inch cube that has a well or depression to accept the smaller cube, and then grow out more. These are great to get a larger plant that will end up in a grow bag of inert media (peppers, tomatoes and the like), as opposed to NFT troughs (nutrient film technique). Everything is a balancing act to utilize all your valuable green house space in best management tactics. The material the pads are made out of is either a crumbly kind of open celled foam (similar to floral foam but a more coarse granual) or rock wool which is a fairly inert but rough, grayish- brown fiberglass like matt. Both pad types are scored deeply threw their thickness about 3/4s the way threw to allow easy individual plant separation. I have used both types but prefer the open celled coarse foam even though it tends to break up a bit too easy. It is less expensive. The rock wool is tougher but I don't like working with those fibre like material as the dust from them is probably not too good for your lungs and eyes if you have to deal with it over time. It is harder, also, to compost when you have huge trash barrels of root waste to "loose". I would like to find, and have played with some other ideas that use natural materials that would allow me to feed the waste roots to pigs, goats, or what ever would eat them. Things like cocoanut husks or some other natural but fairly inert and disease free material. To save cost you can employ a lot of things that allow you to start seeds in welled trays. Cotton does not work as it rots to fast, been there and done that. Coarse peatmoss (spagnum like for hanging baskets) works but you need a lot more extra time/ labor to use it. Depends on whether you use NFT (no media in final growth) or if you choose a media like bark, sand, gravel, pearlite, vermiculite, or combinations of any and all. Cost and your time is everything, especially when you have to seed a tray of 200 plus, plant a grown in tray, and harvest a tray's count of finished product daily, as with herbs and lettuce. Media is available by the case of stacked pads of varied sizes as I mentioned. Add a penny or two for cost per plant unless you use trays of your own local media mix. Loose media in trays works but may need to be filtered out to avoid clogging pumps and lines in recirculating systems, especially the NFT or aquaponic systems. In fish tanks you will have to have better high capacity filtering then as well as skimmers like the protein skimmers.

Answer 2

The plugs are starter pots for seeds and are moved to larger media systems as seedlings. They are made of a variety of materials, depending on the brand. Some hydroponic materials used are coir, peat, bark, pearlite, vermiculite, rock wool, and  coco fiber to name several. They are held together mostly by polyethylene, webbing that will allow the roots to penetrate where the plants can be transplanted with the plug intact.

http://www.greenfinger-hydroponics.co.uk...