Two Easy Tricks to Prevent Mould in Homegrown Sprouts

Growing sprouts at home is an easy way to provide nutritious greens for your family without fancy equipment and a fun winter indoor gardening project. But many beginner sprout growers encounter one big problem that discourages them from trying sprouting again: mould.

Nobody wants to find mould in their homegrown sprouts. Who wants to throw out precious food that you spent all that time growing?

Thankfully, there are two really simple growing tricks that will stop mould in sprouts–with barely any extra work required on your part!

But first, let’s get to the root of the problem…

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Why are my sprouts moulding?

Simply put, your sprouts are sitting in too much water. If the sprouts are too wet between rinses and there’s no airflow, this creates the perfect conditions for mould growth.

Now, on to the two tweaks that will prevent fuzzy sprouts…

1. When it’s time to rinse, do it twice

Sprouts must be rinsed twice daily, but once just isn’t enough. Put water in the jar, swirl the sprouts, and dump the water out. Do it again, but this time, very carefully let the water drain at a 45-degree angle, trying to keep the sprouts as spread out in the jar as possible. Then…

2. Rest the jar in a bowl at a 45-degree angle to drain the remaining water

You know how when you set the jar back upright, there’s always that tiny little pool of water at the bottom? Setting the jar in a bowl prevents water from collecting at the bottom, thus preventing mould.

Finally, when it’s time to store the sprouts in the fridge, there’s one bonus trick to keeping them longer…

Related: Take a Bite Out of Your Grocery Shopping Budget with These Lettuce Growing Strategies

3. Place a paper towel at the bottom of a fridge smart container for the longest possible life

The towel at the bottom of the container will collect any remaining moisture and help avoid surprises. You don’t have to use a Tupperware fridge smart container; a regular plastic container or knockoff will work, too.

Related: How to Start Seeds When Your Home Has No Light or Space

How Do I Start Sprouting At Home?

To start your sprouting journey, you’ll need the following ingredients:

seeds for sprouting
mason jar
sprouting lid
small bowl for tipping your sprouts

If you’re sprouting for the first time or you haven’t done it in a while, here’s how you do the whole process step by step…

Loosely fill the bottom of the jar with sprout seeds.
Fill a jar with water and soak for 4-8 hours or overnight.
You are now starting day one. Rinse the sprouts morning and night, two times each time. On the last rinse each time, carefully follow the tricks above to prevent mould.
Set the jar in a bowl between rinse times. Your sprouts do not need a lot of light so you can keep them in a darker room.
Repeat the process until your seeds are ready, anywhere from 2-7 days depending on the variety of seeds you purchased.
When the seeds are ready, follow the bonus trick to store them so they keep longer.

Related: DIY Seed Starting From Your Window

That’s it! I hope you enjoy your sprout-growing journey!

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Comments

Maureen

Thanks for the tips I have been afraid of salmonella with growing sprouts, I am assuming that two rinses two times a day and the tipping the jar will prevent this.

- Kristen Raney
  
  It should.
  
- Tina F
  
  We do everything that you have suggested and for some reason they still have mold lol. Of course we do live in southwest Florida and have a lot of humidity but I try and keep the AC at a reasonable temp.. also, what keeps the seeds from falling down from the sides? We have one jar that does that..
  
Chris

What are the best seeds to use and where do you buy them. Thinking about trying but I don't want to be stuck with seeds I can only feed my chickens. Thanks for the info on this page.

Sherry

I like your advice about preventing mold. I tried sprouting months ago & like you said, have been afraid to try again. After a few days the smell was horrible. They grew but only filled about 1/4 of the jar. How do you get them to grow enough to fill the jar in less time?

- Kristen Raney
  
  You probably should put in more sprouts than I suggested. Try 3 times the amount next time.
  
- Jon Anderson
  
  Be sure the jar is rested horizontally, and rotating the jar will cause beans and then sprouted beans to cling to the inside of the jar, getting much better aeration .. I think most here will agree that a jar full of sproats is not a good thing! Much less aeration thru the screen that caps the jar ... and too little aeration -> fungus risk !
  
Jessica Coblentz

Which setting do you use for the fridge smart? Open? Half open? Closed?

- Kristen Raney
  
  I use the open setting
  
Leslie

Did your tricks and still have mold. Could I have put in too many seeds, creating too much crowding?

- Kristen Raney
  
  Oh no! Then yes, I would try and put in less seeds next time. Also, it might have something to do with where you live. If you live somewhere near a large body of water, it's likely going to be more humid and it's going to be more challenging to prevent mold.
  
Jon Anderson, MEngr, MD

I've a theory: Pre-soak Tablespoon of Mung Beans in pure water (ya, filtered!) for an hour .. within your 'sprouting bottle with a 'screen lid' .. then dump the water , just tip the bottle .. Then: add a 3% (or even more dilute) hydrogen peroxide! ... Swirl for ? 5 mins, then dump the H2O2 .. Now, rinse those beans twice with pure water, then pour it out, then add your quantity of 'growing water' .. for a final rinse.. Set the jar/bottle on it's side in darkened room/closet/or even oven ... (set to 'OFF', of course!) NOW, see how your beans grow .. handling and watering them in your usual way, but do include the bottle at 45deg in a bowl ... to get good drainage .. Then let us know what happens, 'fungus-wise' ;) Just a thought, but a good one ?

Jon Anderson MEngr, MD

ya, 3% H2O2 is the 'standard concentration ' of 'drug store'/big-box-store' product, btw. It's fairly strong dose! The PRE-soaking should infiltrate the beans so that very little Peroxide will enter the beans .. so , pre-soaking is essential to this experimental process ...

Louise

I have purchased organic broccoli sprouting seeds and now tried two batches. They sprout on day 3 and then remain small, they just do not grow. Rinse 2/3 three times daily. Very disappointed, it looks so easy on all the YouTube videos, help please! Ps using mason jars and s steal mash lids

Tara Fielding

Thank you Kristen. So astute of you to recognise the danger mold presents to your body.

Stephanie

Thank you so much for the instructions! I was sad I couldn’t grow the sprouts I wanted because of all the comments about mold on the internet. Much appreciated.