Microgreens and When to to Use a Blackout Dome

September 17, 2021 2 min read 0 Comments

Microgreens and When to to Use a Blackout Dome

  From our How to Grow Microgreens Series

Transcript is below.

 Nick & Nathan from On the Acre in Houston, TX discuss the topic. 




When to Use Blackout Domes?

We do not use blackout domes unless we have selected that product to grow in blackout specifically. It's not a regular part of our germinating or planting process. When they're stacked, the trays are mostly blacked out, and beyond that, we haven't found it necessary or beneficial to use that method.

What are the Drawbacks to Using Blackout Domes?

I worry, if you're trying to germinate seeds in a blackout dome, you know there's no light, and there's no air movement, and that moisture is just sitting there not going anywhere, so you run the risk of mold or fungus issues that you wouldn't encounter otherwise.


Why do you think that that's such a prevalent problem saying that people are always told to do that blackout? Where did that idea come from? I have no idea; my best guess using domes would be best for people trying to create additional mass; they would use a blackout dome to lengthen the stems. The lack of light causes the stems to stretch toward the light. When there's no light present, they'll continue to grow and grow, and then they can cut at the very bottom, you know, with these long stems and little leaves on top, and they would be able to get more money because they're selling by mass rather than volume. 

Stacking During Germination Vs. Black Out Dome

Using blackout domes would use extra space. Our domes take up more space than when we stack the trays. We do two-three times as many in the same space without domes, so if we use that regularly, we would need so much more room to do what we're doing, and for us, space is a premium. I talked to one of our students a couple of weeks ago, and they're asking how to grow a new variety. They said that they needed like 25 trays a week or something, and they were planning on using blackout domes, and I was like do you know how much space that's going to take? I advised them to use a stacking system because arranging 25 trays a week under blackout domes will use a lot of space.

Using Blackout Domes to Create New Products

Just as an option and the products you get when you use a blackout dome, it's noticeably different like Nathan said, the stems are longer; they have a different color; they have a different taste. We do peas, corn, and sunflower currently in blackout domes.

We have been experimenting with other stuff, but amaranth is next. It gives us another option, and we like to present our chefs with options. It's just another product that we can offer from something that we're already growing in non-black out domes. But the point here is, we're growing it in its entirety in a blackout dome. We're not growing it for just the germination period, then moving into the light. We are creating completely different products with the use of blackout domes.

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