There are many good reasons to re-use a growing medium; saving time, money and being eco friendly are among them. A good quality coco makes this very easy! A good quality coco medium does not break down as fast as other media, like peat. As coir does not tend to be easily struck by disease, which makes for a very good medium to re-use. Potentially up to a few times before discarding to the garden where it makes a great soil amendment.
1. Before re-planting, first verify salt levels of your coco. If the previous crop ended properly, salt levels should be fine. In any case, you should always proceed to the 1:1.5 extraction method to be sure. Keep in mind that high salt levels can reduce crop potential.
2. While you’re digging your coco for test samples, look for critters. If you happen to see an overwhelming amounts of bugs, you might want to skip re-using and go straight to soil amending.
3. Avoid using “re-used” coco for seedlings or young cuttings; these are by definition, quite fragile. Therefore starting in new, fresh coco is a safer path. Re-using coco should be saved for healthy thriving plants.
4. Once the crop is finished, pull the old root ball out (some people use a knife or small saw to carve the stump out). Put in the new plant and fill the gap around the new root ball with new coco. The final stage of the previous crop might have lowered the intensity of the calcium buffer, which will be replenished as you feed your plants. When emerging roots get to the re-used coco part of the container it will all be perfect and balanced again.
5. Water profusely with calcium rich, coir specific nutrients and a good rooting stimulant until run-off occurs. Then inspect carefully to make sure there are no air pockets (fill them up with fresh coco if needed) and that is it!
Enjoy your saved time and money!
Some growers are hesitant to re-use their coco because of the decaying dead roots that remain. Using a quality enzyme product like CANNAZYM will decompose those roots before they become a food source for pathogens. On top of increasing aeration in the growing medium along with providing nutrients for the plant and beneficial microorganism of the root zone.
Used coco is very good to amend outdoor flower beds, gardens or any other area where the soil has compacted. It will bring back aeration as well as improving water retention.
