Growing microgreens without soil is becoming more common.
I’m sure you’ve seen photos on Instagram of beautiful microgreens growing on thin fiber pads.
These pads can be made of wood fibers, jute fibers, felt-like materials, or coco coir fibers.
Above are three of the most popular microgreen growing pads. Click the each image to get more information.
Growing Microgreens Without Soil
Let’s face it, working with soil inside your home can make a mess. Soil has also been blamed for bacterial and fungal issues on microgreens. Fiber pads may remove the need to wash your microgreens before consumption.
But that doesn’t necessarily mean growing microgreens in soil is a bad idea. Soil also has many advantages.
Especially for those of us that have busy schedules and are prone to forgetting to water your plants. The volume of soil retains more water than the thin fiber pads regardless of what their marketing propaganda suggests.
Soil also provides nutrients for the young microgreen seedlings. Yes, the cotyledons in seeds do contain a lot of energy, but as the microgreens grow in trays, they require additional nutrients provided by a good professional soil mix.
I’m using the term soil even when the growing medium might be considered soil-less as in coco coir potting mixes. It’s just easier to say soil than potting or starting mixes.
Time & Space is Money for Indoor Gardeners
As an indoor gardener, I have limited space, time, and money to grow nutritious vegetables and greens.
As such, I’m always looking for a better way to grow vegetables and greens. Whether it be cleanliness, efficiency, or cost. But ultimately, the more productive method is the one that I’ll choose over the others.
Growing Microgreens Without Soil - A Test
Fiber microgreen growing pads would be ideal for me.
Storing soil takes space. I only have so much storage place in my house. Besides, the soil bags are heavy, and I need to drive to a hydroponic speciality store to pick up a bag. While fiber pads are delivered to the house.
Soil can also make a mess, both when starting microgreen seeds and during harvest.
There’s a belief, whether true or not, that soil can cause fungal disease and bacterial problems such as E. coli on the harvested greens. Therefore, some regulatory agencies require microgreens grown in soil to be washed before selling them.
Furthermore, I’m selling media for growing microgreens and shipping soil is many times more costly than it would be to mail a thin fiber pad.
That said, I’m still not giving up time or productivity to grow mine or my customers’ microgreens over a bit of mess or the cost of shipping. Quality and quantity is more important to those of us with limited space and time.
So, the best way to see if growing microgreens on a fiber pad or on soil is better is to design a microgreen growing test and compare the rate of growth and harvestable yield.
Below is such a test.
Microgreens Grown In Soil
I regularly use FoxFarm Bush Doctor® Coco Loco® potting mix to grow microgreens.
Besides coco coir, Coco Loco contains aged forest products, perlite, earthworm castings, bat guano, kelp meal, oyster shell, dolomitic lime, and well as beneficial mycorrhizal fungi.
You can purchase small bags of the soil mix I use from the Home Microgreens Store.
Microgreens Grown on Jute Fiber Pad
I cut GreenEase Jute Micro-seed pads to fit into the same size container used for soil.
The micro-seed pad is made of jute.
Jute is described by as natural fiber designed to effectively control water, allowing seeds to thrive in a variety of hydroponic systems.
I tested two watering methods using the jute fiber pad, a shallow tray where water would stay and be absorbed, and a deeper tray which could be watered from below similar to the soil tray.
Microgreen Grown in Soil vs. Fiber Pad
The surface area of all three trays is the same.
The same weight of Tatsoi seed is applied to the surface of the soil and jute fiber pads.
Both the soil and jute fiber pads are pre-wetted with a spray bottle and also sprayed after planting.
All three seed trays are placed on a Vivosun Seed Heating Mat with covers over them.
Photos of the Microgreen Jute vs. Soil Test
Pictures tell the store. Below are side-by-side comparisons of the microgreen growth over nine-days.
Click to expand images if you're viewing the post on a computer.
Day 0 - Seeding
Day 3 - Sprouted Microgreens
Three days after seeding the trays there isn't much difference between the trays. The germination rate is a bit lower on the shallow tray.
Day 5 - Seedling Microgreens
As you can see, the microgreens grown in soil are starting to grow quickly; they're more dense, and the leaves are larger overall.
While the microgreens in the more protected deep tray are growing better than those in the shallow tray. The unprotected tray dries out quicker and has more exposure and is more vulnerable.
The microgreens grown in soil have a more stable environment, more consistent moisture and temperature, as well as, more room for the roots to anchor the plant.
Regardless of what others say, nutrients in the soil are having an affect on growth.
Grow Your Own Microgreens
Visit the Home Microgreens Store and shop for microgreens kits, equipment, supplies, and microgreens seeds.
Microgreens are easy & quick to grow!
Day 7 - Harvestable Microgreens Grown In Soil
It's obvious that the microgreens grown in the potting soil mix are growing quicker and better than either of those grown on the jute pad.
If you have any doubts take a look at the photo below that was snapped on the ninth day after sowing the seed.
Is It a Good Idea to Grow Microgreen Without Soil?
No, it's not a good idea.
Growing microgreens without soil may be cleaner, a bit less of a hassle, but in the end, the microgreens don't grow as quick. The yield is also much lower.
For the Home Microgreen Gardener growing on fiber pads will cost you time and produce less nutritious greens.
Is This Test Scientific?
Look at it this way, growing microgreens at home isn't scientific either.
We pay as much attention to our plants as we can. But there are times when life gets in the way.
I didn't ignore any of the trays during the nine days. But I also didn't cater to them every hour.
Microgreen seeds grown in soil grow faster compared to those on jute fiber pads.
Will results vary? Most likely to some degree they will. I've seen many photos of beautiful microgreens grown on fiber pads.
The question is how were they grown? Did they have a constant supply of fresh water, were they grown in a protected environment?
For the home microgreen grower it's best to use a premium potting mix. You'll see quicker results and not have to tend to them as frequently.
Have a Question?
If you have any questions about the information in this post or microgreens in general?
Please leave a comment below or reach out to me using the Ask a Question page.
Leaving a comment or using the Ask a Question page does not add your email to any mailing or marketing list.
Microgreen Kits & Seeds
Grow Microgreens in Your Home!
Shop for Kits, Equipment, and Seed.