Mucilaginous is a word you come across often when reading microgreen articles. Many microgreens have mucilaginous seeds, but what does this mean for the microgreen grower?
This article will explain mucilage and how to grow microgreens with varieties that have mucilaginous seeds.
The cover image of this article shows Genovese Basil seeds after they’ve been wetted showing the mucilage. Those seeds grew the harvested basil below.
Mucilaginous Seeds
Let’s start by pronouncing mucilaginous. Pronunciation or reading phonetic notation – ˌmyü-sə-ˈla-jə-nəs – is not my jam, so I always defer to this lady – Click to visit Merriam Webster pronunciation page for mucilaginous.
Mucilage is a gelatinous substance secreted by plants composed of proteins and polysaccharides. Mucilaginous is an adjective that modifies mucilage, meaning “full of” or “secreting” mucilage.
The whitish substance around these Genovese Basil seeds is mucilage. The jelly-like substance forms quickly on seeds.
For example, look at the two photos below. Both trays contain Red Rubin Basil microgreen seeds. The first photo is of the planted seeds before the seeds were sprayed with water.
According to the data recorded by my camera, the second photo was shot three minutes after the first. So almost immediately after being wetted (I had to put the camera down, spray the seeds, and take the next photo), the seeds secrete mucilage.
FREE Home Microgreens Grow course that teaches you the basics of growing microgreens in your home! There are 12 video lessons (over 120 minutes), downloads, and more written information and tips!
What is the Purpose of Mucilaginous Seeds?
The short answer is protection.
One apparent reason, based on how quickly the mucilage forms, is to retain moisture around the seed.
The gel could also regulate the moisture that reaches the seed and growing embryo. The polysaccharides will put water to it when available as it dries and repeals water once it reaches the saturation point.
There are many other possible purposes for mucilage too. Such as, the gel holds onto soil particles for the seeds, protection from UV rays, and maybe the most interesting is allelopathy.
In allelopathy, the mucilaginous seed gel secretes chemicals that influence the germination and growth of neighboring seeds and plants.
Not in a good way for the neighboring seeds. The biochemicals would retard the growth of the adjacent seeds and plants, giving the mucilaginous seed an early growth advantage.
The mucilage could also deter other organisms from consuming the seed and young plant.
Mucilaginous Microgreen Varieties
According to Wikipedia, nearly all plant seeds produce mucilage to some extent.
The microgreens that produce enough to be visible are:
- Basil;
- Arugula;
- Cress;
- Flax;
- Radish (minor);
- Mizuna;
- Chia (that’s why they grow on chia pets so well!); and
- Some mustards.
Home Microgreens Store
Tricks to Growing Mucilaginous Seeds
Often mucilaginous microgreens are labeled as harder to grow. Below are some methods that will make it easier for you to grow these microgreens.
The first suggestion for growing mucilaginous seeds is to not pre-soak them. In fact, there are a lot of microgreens that growers suggest to be pre-soaked, but we’ve found that practice unnecessary.
Soaking them would make a gelatinous mess.
Second, spread the seeds evenly. If it’s true that seed mucilage produces growth retarding biochemicals, any seeds touching each other may hinder each other’s growth.
Third, don’t spray them with water after the initial misting.
The mucilage will provide more than enough moisture for the seeds to germinate and start growing. They may also draw moisture from the pre-wetted soil surface.
Fourth, leave them alone and don’t check on them as frequently while they germinate.
We’ve found mucilaginous seeds are very sticky and adhere to the tray covers.
When you lift the cover, the seeds stick to it and increase the chance of killing the seedling, especially if weight is added to the top of the trays.
Leave them be for several days, let the seeds germinate, and start growing before you check on them.
We will test whether growing mucilaginous seeds with a raised cover is better. Basil will probably be the test subject.
Hopefully, these suggestions will make it easier for you to grow these microgreens.
What is Your Experience with These Varieties?
Let us know by commenting below if you’ve had problems or good luck growing mucilaginous seeds.
If you have any questions about the information in this post or microgreens in general, please comment below or contact me using the Ask a Question page.
We’d love to hear from you.
Hi, thanks so much for the article! Can you clarify what you mean when you say “ Third, don’t spray them with water after the initial soak.” You recommended not to presoak, so does this mean to wet the soil, spray the seeds once you’ve placed them and THEN don’t spray them for a few days while they are weighted?
Also, have you any recommendations for growing arugula? I have tried but find that the mucilaginous coating makes the husks stick to my arugula stems, which I find unappealing to eat. Any tips on how to avoid having the husks stick this way? I am planting in ProMix HP, no weight, 6 days blackout (to try to get them taller in this cooler weather), grow lights. My harvest height was about 1.5 inches tall.
Hi Debbie,
Bad choice of words. I changed the text. You are correct; wet the soil, mist the seeds with a spray bottle, and then leave them alone. The next time they are watered is when they come out of the blackout and are bottom watered.
I’ll do an arugula article soon; just put it on the list. I grow arugula just like I do amaranth. A link is below. I use the dome method, which I will also do an article on soon. The dome allows the plants to grow taller before they go under the light. Arugula tends not to grow much taller once the light hits it. Not sure why it grows taller in the garden. Maybe the sunlight has more energy or LED’s don’t have the wavelengths it needs. Not sure. Anyway, I let it grow until it touches the top of the dome, then place it under the light. I use the watering tray as a dome.
I hope this helps. Here’s the amaranth article.
https://homemicrogreens.com/amaranth-microgreens/