From our How to Grow Microgreens Series
Transcript is below.
Nick & Nathan from On the Acre in Houston, TX discuss the topic. For more advanced microgreens business training, visit our Urban Farm Academy Business of Microgreens course.
So whenever we're germinating microgreens we end up stacking them after they're planted all on these racks. The bottom shelf is typically used for the stacked whereas the top two shelves are for our domes. You'll see that we have a variety of different tray sizes represented as well as these bricks on top, a really cheap solution is to go buy some jars and fill them with sand and it works really well like to distribute weight around and it doesn't cost very much money. Bricks don't cost much money either but they are very much you know one particular shape yes that's a great distinction.
So what's happening here is the seeds have been distributed evenly across the surface of the trays and the top of the soil has been moistened very well and these seeds just they sit here and they soak and eventually they start to sprout and in about four days they're ready to unstuck in about a week they're ready to be moved from the domes into the light. The lighting that they get in here is fluorescent lighting. We have our office in here also so it's dark at night light during the days while we're in here year there's no special thing that happens lighting wise for them like we've talked about before they are in the dark because they're stocked under one another - the domes.
As we move into the colder months right now we've just recently brought out our heater because germination slows whenever it's cold and the colder it gets the slower the germination takes place but we need germination to occur at a constant pace that way we know when our plants are going to be ready and in order to do that we try to maintain a temperature of around 65 to 73 degrees in here because that's what we keep it up during the summer when it's warm so as long as we maintain the same conditions year-round then the plants will react the same way.
We talked a little bit about light and humidity is another factor you need to take into account so one of these simple little magnetic thermometers. We have a meeting room tell us the temperature and humidity in the room hydrometer is the word that you look for when looking for a humidity reader.
If humidity gets too high we use a dehumidifier in our grow room and depending on what it's outside you could open it we know if you wanted to but then you're letting in things from outside allergens pollen things like that so we have a dehumidifier for that case it's also nice tells you average highs and lows for a day so it lets us know wow we are not there if there's temperature changes going on so that we can be more aware they overall.
You can see the range in here is from 59 to 46% humidity and 74 to 68 degrees Fahrenheit we're trying to keep humidity below 70%. If you get up into the 80s is where you really start to to see problems with mold and fungus etc so we give ourselves that 10% buffer zone to keep it safe so if it does get up at 75 you know occasionally it's okay. But you really want to stay below 80 because that's when it starts to get a icky.
When talking about microgreen germination we went ahead and brought down three of our trays for you, we removed the domes from them so you can see what stage you're at this right here is amaranth and it's ready to be moved into the light you can tell that because of how tall the the amaranth plants have actually grown and there's going to be some close-ups of the amaranth so you can actually take a look at the roots and how they grow and how the plant comes up.
The next tree you're looking at is lemon basil and it is just the right time for it to go over it has about fingerling stem so maybe about an inch stem on it and might not be able to see here but there's a little bit of a directional like movement to both here and here that's like I told you our light sources here and our germinations against the wall so they pull a little bit towards the light as a germinating and then they fix as soon as you get them into the grow room the lights directly above them.
That is called atoleation, whenever a plant reaches for the light and that is what when you use a blackout dome, that is it the reason that they stretch that the stem stretch because the plant is using all of the energy located in the seed to grow the stem it thinks it's going through soil because there's no light yet as soon as the light hits the leaves the cotyledons start producing energy for the plant to continue growing so that is why they lean towards the light because they're not getting quite enough yet.
The tray on the end is our miracle farms and we had three different varieties in these the closest one to us as carrots then you have bunching onions and on this side you have celery so we have they've all were planted at the same time and are in a different stage of their germination the celery there's no visible stems coming up yet and then our carrot and onion are both at about like a half inch to three-quarters off the soil we would leave these over here for probably at least another couple days before we transfer them to work we're room and put under the light.