Coconut coir (also called coco coir, coco peat, or simply coir) is a soil-less potting medium made from coconut husk residue.
The natural, fibrous material, coir
is growing in popularity as an alternative to sphagnum peat moss and other potting mixes because it’s renewable: 50-200 coconuts can grow per tree a year, meaning as coconuts continue to grow, be harvested, and processed, then exteriors of the nut can be used for coir.
Gardeners are excited about coco coir (pronounced “kwaher”) because it drains well and needs less watering than most potting mixes.
Coco has also become a favorite soil-less medium in hydroponic gardening.
Coco coir comes in several forms.
Brick or bale. These compressed blocks take up less room and weigh less to buy than the hydrated equivalent – a helpful factor if you’re ordering by mail or if you simply have to cart the stuff home from the garden center. The disadvantage of coco coir bricks that you must hydrate them before using – most often by submerging them in water. Be ready for an adventure. Coco absorbs up to 5 times its volume in water. Packaging will contain clear instructions for adding water, but be careful to add it gradually because fibers act like mini-sponges. If you’re not paying attention, you could have a “coir explosion” on your hands (or in your wheelbarrow, whichever the case may be.) Fluff the hydrated stuff with your hands to make sure the fibers are separated from one another.
Pellets. Convenience is the name of the game with these nifty individualized cubes. Place them in your growing container, add water, and they will expand to fill the pot – with little or no mess. Burpee carries coir pellets in two sizes: regular size pellets
, which expand to 2 inches in water, and XL Super Growing Pellets
Hydrated. Water is already mixed in.
(Gardener’s Supply) which have had excess salts removed.
Coco coir has been seen to promote excellent plant growth. However,in a study by Utah State University, sphagnum peat moss outperformed coir. When combined with sphagnum peat, your favorite potting mix, or other nutrients, coir offers a win-win solution: an environmentally-friendly way to start seeds, increase water retention, prevent disease, and keep maintenance at a minimum. Natural BeginningsTM Seed-Starting Mix, for instance, is made from coconut coir, worm castings, and mealworm guano.
You can also use coir as a growing medium in conjunction with a wicking mat
to maximize drainage and moisture balance.
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