When using a grow pad in 10”X20” trays, and trying to select the right one, it usually will come down to what they are made of, how long they’ll last, and how they hold and transfer water within the pad.
Most pads are not re-useable. Microgreen roots occupy every square inch of these pads and so after harvest, and drying them out, they either fall apart, or they’re compacted and don’t absorb water like they did when they were new. Reusing pads also asks for root and seed diseases that can effect the next crop.
Biodegradable Micro Mat™ Pads
Most biodegradable Micro pads contain some type of wood fiber that will break down readily with a little help when you throw them in the compost pile. The advantage is that they are fairly absorbent and for their first use, can hold your greens very well.
The downside of some of these types of pads is their strength. They have been known to break down and fall apart which can make ‘pull and cut’ methods of harvesting a nightmare.
Some pads, like the Biostrate ™ pad, are a felt pad, also comprised of biodegradable materials, but do not break down as rapidly as the wood fiber types. They claim they can be composted, but not recommended for the backyard composter because they take much longer to break down.
Coco Coir Mats
There are a few product lines that use coco fiber, sometimes blended with rubber or biodegradable latex glue material. They are biodegradable but do so pretty slowly due to their fibrous nature.
If you’re using burlap or other fibers that come to mind, the most important consideration is their ability to retain water consistently while also providing an open fiber for the roots to grab on to. Go ahead and try a couple different fibers and see how they do.
One suggestion is to soak the fiber in pH balanced water, and let it soak for several hours, then drain off the effluent and check its pH. You may find that some will drive pH up or down and you’ll want to adjust your pH accordingly.
Regardless of the grow pad you use we strongly suggest a strong and durable 1020 tray. The last thing you want to have happen is for your tray to crack or break while moving your microgreens around. We also want to save money and the environment by reusing our trays for many year. Therefore we recommend you picking up these Extra Strength Propagation Trays. After a single reuse the cost savings will far outweigh any other trays you can find on the market.