Testing Different Growing Mediums and Containers
We tested a few different growing mediums in our germination box to see how well they would perform. Planting can sometimes get very expensive, so we try to get a second use out of items around the house that would normally be discarded. We tested several different types of seeds along with different types of materials. This was our process and these are our results (so far).
Materials
Molded Paper Pulp Container
Commonly used as packing material. These containers are usually sustainable as they are produced from recycled materials, and can also be recycled again once discarded. They are most used as disposable food and beverage trays that you would find at fast food restaurants, movie theaters, and sporting events.
Vegetal Cellulose Sponge
Commonly used as a dish sponge. This specific one is made from recycled material and can also be recycled or composted. Make sure you check the material when you buy sponges as they can be made from synthetic materials that can not be recycled.
Melamine Sponge
Commonly used as a cleaning sponge. Although one of the best options for cleaning, this sponge is not easily recyclable or compostable making it even more important for us to get a second use out of it. Melamine can also be found as cookware.
EPS Foam Packing Material
The most common foam used in packaging- EPS stands for Expanded Polystyrene. This material can be found not only as foam, but also as clear containers for food packaging. EPS is recyclable, but not biodegradable. Most people use something made from EPS on a daily basis. We used this small piece of foam pictured here to hold soil (for testing ONLY we do not recommend using this type of foam directly with soil long term), but also used a large foam box as a germination container.
Cellulose Fiber Tissue Roll
Commonly found in the center of paper towel and toilet paper rolls. Biodegradable and recyclable, these rolls are used by almost everyone on a daily basis. Rolls are held together with a non-toxic glue. We folded ours down so they could stand up on their own and hold soil.
Method
Before putting seeds in our growing mediums, we designed a small germination box with our second use foam box (learn how to make your own germination box here!). We wanted something that wouldn't take up a lot of space, was insulated, and we also didn't want to have to go out and buy something. This was our final result.
As for the containers and growing mediums, we gently filled our paper towel rolls, and second use packaging with soil. Folding down one side of the roll allowed them to stand upright. The sponges were a little large for just a single seed, so we cut them in half to try different varieties of seeds. We made a very small cut in both types of sponges about 1/4 inch deep to make sure they would be covered. Since there were two of the foam packing containers, we added the sponges to our extra one to provide a waterproof bottom.
Everything fit perfectly in our germination box. We planted the seeds accordingly and thoroughly misted the soil. These were the seed types we used for each growing medium:
Paper towel rolls: Organic Valencia Tomato, Black Cherry Tomato, Vintage Wine Tomato, Bradley Tomato, Sugar Snap Pea, Yankee Bell Pepper, Cayenne Pepper, California Wonder Pepper, Chocolate Bell Pepper
Melamine Sponges: Cilantro, Red Radish, Royal Burgundy Bean, Cucumber
Vegetal Cellulose Sponge: Lemon Balm, Zucchini
Molded Paper Pulp Containers: Spinach, Broccoli
Foam Packing Container: Kale
Results
Day 1
Day 3
Most of the seeds have hooked or fully sprouted at this point. You can see the seeds have sprouted in some of the sponges, but have not yet breached the surface.
Day 10
Everything has really taken off and seeds have finally sprouted through the sponges. At this point, we had to transplant our sugar snap pea and also checked on our royal burgundy bean which seemed to have trouble with the melamine.
Upon closer inspection, it looked like there could have been two issues with this seed. The seed did sprout, however, the sprout was not strong enough to push through the sponge. The sponge also developed a mold that we did not see until we took it out of the germination box.
Day 16 - Final Results before transplanting
Overall very pleased with our experiment. All seeds sprouted and the only trouble came from sprouts not being strong enough to push through the sponge. Our cilantro, lemon balm, and royal burgundy beans were the only sprouts that had an issue with the sponges. However, the red radish, zucchini, and cucumber had no issues. Roots were able to go though the sponges and the molded paper and made transplanting really easy. All of this was done indoors over a two week process. The only thing I would change would be removing the scouring pad from the sponge to allow the roots to go through.