How to Grow Sunflower Microgreens FULL WALKTHROUGH + Tips & Tricks
If you're looking to grow perfect trays of sunflower, you are definitely in the right place. I'm about to give you a full walkthrough, along with tips and tricks on how to grow high quality sunflower microgreens every time, with no mold and high yields.
To be honest, sunflower microgreens are not my favorite to grow, and they've given me plenty of problems over the years. They require more effort than most other varieties, and if I could do without them in my business, I probably wouldn't grow them. Sunflowers are very popular in the health niche, and because my business services this niche, it’s important to grow them. There is high demand, and I do sell a many sunflower microgreens, so I've had to really master the process of growing them.
I'm sure you want to improve your sunflower microgreens, so let me take you step by step to show you exactly how I grow mine. This will be a full walkthrough.
It all starts with high quality seed, and the seed variety to use is called black oil. I'm not going super deep into the seeds in this post because I actually have a separate post dedicated to this subject. This being said, it is much easier to grow high quality sunflower microgreens if you are using high quality seeds in the first place.
Aside from the seeds and your grow room environment, it's all about your process. Before I jump into mine, I just want to mention that sunflower microgreens may grow better in an environment that has a higher temperature. Nevertheless, I've had no problem growing them in temperatures as low as 68 degrees Fahrenheit and as high as 77 degrees Fahrenheit.
The first step in growing your sunflower microgreens is soaking the seeds. This helps to fully activate the seeds, resulting in thorough germination and a high germination rate. My trick here is to soak them for only FOUR hours. This is extremely important and was a huge game changer when I reduced my soak time down to four hours. It made a world of a difference will all seeds, good and bad. Keep in mind that sunflower seeds do float, so you will need some sort of system in place to keep the seeds under water. If they end up floating to the top, they absorb water correctly. I use strainer bags which make it easy to soak seeds. And for the sunflowers, I simply put a brick on top of the bag, that way they don't float up to the surface.
Your seeding rate is something that you will have to experiment with in order to figure out what works best for you. Every seed lot will perform slightly differently, so you might have to change your seeding rate based on the lot of seeds being grown. And don't forget that every microgreens farmer has a different grow room and different procedures. Learn what works best for you. With this being said, the seeding rate that I've been using is five ounces of dry seeds for each 10 x 20 tray.
After soaking your seeds for exactly four hours, drain the water. You can seed them into trays right after draining the water, or you can let the seeds dry off for a few hours. This makes it easy to seed them because they don’t stick together.
Now that your seeds are soaked, it is time to start prepping your tray. Each tray is actually two trays, one tray with holes that sits inside a tray without holes. Add your growing medium. I highly recommend using a potting mix similar to the one that I use, which is called PRO-MIX MP ORGANIK. Make sure to spread your growing medium evenly across the tray, and be especially careful to get it into all the corners. If you don't, your potting mix won't be able to hold as much moisture in those areas and your sunflowers will actually get dehydrated and fall over in those specific areas.
Next, press the soil down with either a soil press or another tray, that way you have a nice even and flat surface to spread your seeds over. Spread your seed as evenly as possible across the tray, and if making multiple trays at a time, make sure to try and get the same amount of seeds into each tray. Give your trays and nice watering. I used to use the mist setting, but now I actually just use the shower setting. I find that it's faster, more thorough, and more efficient too, because less of that moisture is just evaporating and going into the air. You want the plants to get enough water to last them through the whole germination process, but don't oversaturate the soil, creating an anaerobic environment.
Once your trays have gotten that initial watering, stack them and place a weighted tray on top. I use a 14 pound paving stone to add weight, which I purchased at Lowe's. The weight forces the plants to become strong because they have to push up against it, which also helps them push their roots down into the soil. Otherwise, the seeds may simply germinate/sprout on top of the soil, never getting rooted and die. Stacking trays during germination also helps maintain a dark and damp environment, which is ideal for germination.
Once you see the sunflower microgreens pushing up on the trays above, they're ready to be moved from germination and go under lights. Your germination time will vary based on the temperature in your farm, your seeds, your procedure, etc, but my germination time is between three and four days. Lately, I've been doing three days in germination because if I let them go the extra fourth day, they actually push up so much that the stack of trays falls over.
When going under lights, they should look young but healthy and just about every seed should have germinated. What you’re really looking for is a high germination rate and little to no mold on any of the seeds, or spreading throughout the tray. If you happen to see a little bit of mold in your tray, I would just ignore it because it probably won't cause an issue. When you give the tray its first watering, along with the fact that they are now getting that air flow, chances are the mold will just disappear and never proliferate.
Since the plants haven't had water in a few days, they will be thirsty when you first put them under lights. Right after they go out, give them a good watering from above. That's right, top water. This will allow the seed hulls to absorb some of the water, weakening and loosening them for easy removal. You will keep top watering for the first two or three days they are under lights. I water once per day in the morning, keeping the soil moist, but not completely drenched.
Starting on day two or three under lights, after the plants have grown a bit, start brushing the hulls off of the trays manually with your hand after each watering. Do this everyday after watering until they are ready for harvest. Most of the seed hulls will fly off after the first 1-3 days of doing this. I always keep my sunflower trays on the bottom shelf of my grow racks so when I'm brushing off the hulls, they fall onto the floor instead of into the trays beneath, potentially causing problems.
If you have multiple stages of sunflower growing at the same time on your racks, brush the oldest plants first, and make your way towards the youngest plants. The older trays will be cleaner because you have been knocking the seeds off each day. Don’t start with the younger trays, get your hands all dirty, and then wipe the dirt onto the older trays.
Around the third or fourth day that your sunflower microgreens trays are under the lights, switch from top watering to bottom watering so that your plants aren't wet when it comes time to harvest. Even though you are bottom watering now, keep brushing the hulls off after each watering.
On the sixth or seventh day that my sunflower microgreen strays are under lights, they're ready for harvest. You should have a similar situation, but this will be determined by the nuances of your grow room and your seeds. At the time I'm shooting this video right now, I've been averaging a yield of about 23 ounces per tray for my sunflower microgreens.
Link to this video: https://youtu.be/RzCYKPnvOr4