I mixed coir with a good, professional grade potting mix. I never had an issue with the soil hardening. I used both earthboxes and the eBuckets. The earthboxes I used for 3 years without changing out the potting mix/coir. I did always remove/replace the fertilizer strip and, of course, remove the old plants and roots each year. I have been away from gardening for the past couple of years and will start up a couple of earthboxes this year. I no longer have space for a real garden and will be limited to just 2 or 3 earthboxes this year. I am looking for a good professional potting mix but can't seem to locate one in this area and shipping costs make it prohibitive to order online.
The eBuckets do have a space for aeration and I believe the earthboxes also have a space above the water line and below the screen. I just like the concept of both and they make it very easy to grow plants ... the plants get/use only the water they need (assuming you keep water in the reservoirs).
