Chapter 4 - Learn how to Easily Grow Microgreens in less than 1hr a week: Where, When, How, What Starter Kit needed
IN THIS LESSON
You'll learn the method that I found works best to grow & harvest Microgreens at home; and answer your frequent questions:
How to harvest Microgreens,
How long to harvest,
When is the best harvest time,
What Microgreens yield to expect,
The harvesting tools you need,
Rinse, Wash & Repeat,
How to store Microgreens seeds.
So if you want start growing Microgreens, this lesson is for you.
Harvesting Microgreens
When to harvest Microgreens? How do you know when microgreens are ready to pick?
After 7-15 days growing for most varieties, when the first “true leaves” unfold, with a deep green colour and of good size (typically 1.5-2.5 inches or 5-7cm tall), it’s ready to harvest. You will harvest both the leaves and the stems.
While some studies recommend harvesting the Microgreens at night or in the morning, it ignores the very quick loss of nutrients after harvesting (remember the research on effect of storage on nutrients we covered earlier in this Guide?).
Due to their delicate tissues, fresh cut microgreens showed a shelf life not exceeding ten days at 5 °C.
so, best to eat them fresh, immediately!
Shelf life at 4 °C, based on visual quality, averaged 21 days for radish, and 14 days for arugula and red cabbage at 4 °C
(Berba & Uchanski, 2012).
What Microgreens yield per tray should I expect?
As mentioned earlier, Microgreens is still a field that hasn’t been researched much, in particular on yield optimisation.
Yields are not just about seeds density but in fact more about light exposure and controlled environment.
The seed densities did not correlate with yield as expected. Light exposure and season appeared to be more influential to microgreen yields than seed density.
Effects of Seed Density and Other Factors on the Yield of Microgreens Grown Hydroponically on Burlap
If you follow the method described in this Guide, you will however benefit from a proven process that delivers high yields (without fertilisers!), based on latest research available so far, with specific and comprehensive recommendations for growing medium (in particular hydroponic method here), light exposure, temperature, ventilations, moisture levels, etc.
As always, I refer to the latest research to support my recommendations:
Johnny’s Selected Seeds did a trial in 2017 to compare varieties of Microgreens to consider seeding density and yield – see their yields results for 29 Microgreens.
Johnny's 2015 Microgreens Yield Trial
The use of nutrient solution at half strength gave both a high yield (0.23 g cm−2) and a desirable seedling height.
How to harvest microgreens?
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Harvest only what you need to eat immediately – don't wash or cut the whole tray if you don't need!
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The easiest way I’ve found using the growing method in this Guide is to take one of the coco fibre pads out of the tray, hold it and simply rinse gently under a tap and shake out the water.
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You can then use the recommended harvesting tools on my list scissors or a sharp steel knife to cut the stems out about 1cm above the grow medium (to avoid any grow medium or potentially any mold in your plate!). If you have a larger number of trays to harvest, you might want to consider an electric shear.
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You can then put the harvested Microgreens in a salad spinner to wash further and remove any remaining water, and they’ll be ready to enjoy immediately!
Tip: If you do that, avoid using your tap's city water! best to use some of your filtered water
Get a spinner here:
Clean the Microgreens Trays, Rinse & Repeat!
Don't skip those steps!
Once you've harvested you aren't quite done yet, and you need to get ready for the next grow cycle. I know it's not the most exciting part of growing Microgreens but it's critical to set you up for success on the next cycle, so follow this simple routine EACH time – no skipping if you want to avoid mold and other nasty pathogens that could develop and make you and family sick!
How to clean and sanitise Microgreens trays
Trays will need to be cleaned after every use. This includes trays used for blackout and bottom-watering. I recommend using hot soapy water with a basic detergent (no bleach). It is important to clean out all debris as it could cause mold for the next cycle. After rinsing the trays, spray down each tray with a diluted H202 solution. Let air dry and store in a clean, dry place. High-quality Microgreen trays will last years if you take care of them. Try not scratching the trays so there is less chance of bacterial growth.
Learn how to clean Microgreens Trays
How to store Microgreens seeds
Instead of finding ways to store seeds longer, I’m recommending to simply buy seeds in smaller quantities (lets say enough for 6-9 months so it's more cost effective for you) so you don’t risk storing too much seeds which may not perform well if stored in the wrong conditions.
I buy most of my seeds from Natures Root in pouches as shown on the picture below with a zip to keep them air tight and waterproof! If yours doesn’t come with a zip, you can simply use a ziplock bag (make sure you keep it out of light though!).
You can store the bags either in a cooler garage, or in your fridge.
