OK, I know when to say I was wrong. After visiting many sites and speaking to people that I know, who are aware about worm tea vs. leachate I have to say: I was wrong about using it. That is not to let you think that I have not used it, without any ill effects to my garden plants or to me. From now on, I will not use it except to pour it into my hot compost bin. The overwhelming evidence does show that it is toxic to plants and people, as it has within it inherent attributes which we should all not use.
To back track just a bit here I will go back to the basics of composting with worms. The various stages that are inherent in the process are below.
Composting with worms is a more controlled method of basic composting as well as it does speed up the process. Your bin is, I hope, maintained at a constant temperature, which enables the most active bacteria, Mesophilic to take over. The worms move through the organic matter helping to aerate the decaying matter, as well as making the smaller particles of the decaying matter smaller, this leaves more surface area for beneficial microbes to work on.
If the bin moisture content gets too high, (usually above 80%), the decaying matter becomes compacted, the same way the landfill does. This is when the worm bin can begin to change over, to those icky and nasty anaerobic organisms, which can be harmful to your worms and even begin killing them off.
Once the moisture content begins to rise even more, the decaying matter releases a liquid called leachate. You will read on many websites that refer to this as worm tea, which it is not.
You make worm tea by brewing worm castings, which are chock-full of aerobic microorganisms. This process is accomplished by aerating the worm castings, water and molasses, which has no sulfur in it, for approximately 48 hours in order to explode the aerobic microbe population.
Leachate is usually the opposite, full of anaerobic organisms.
If you are getting a little leachate from your worm farm or worm bin, try adding several inches of dry shredded newspaper on top and place the lid on it. This will absorb a little of the moisture. If you are getting a lot of leachate, it might be time to remake the bedding for your worms. I also do leave the bin top off during the day light hours for perhaps three days in a row. Please be sure to cover them if you do this at night. All the predators in your neighborhood will be feasting on your worms otherwise.
Below is what I received from a fellow worm bin enthusiast:
By the way, do not believe it when you see people saying that the brown liquid that seeps out of worm bins and tray stacking systems etc is “great fertilizer” or “worm tea”. It is not great fertilizer, it is anaerobic, and should not go anywhere near growing plants or living soil – it should not even exist, all it means is that you have let your bin get too wet. Food wastes are about 90% water, and worm feed (including bedding or whatever) should not be more than about 75%
moist. Well-managed worm bins do not seep. You can add the brown liquid to an ordinary compost pile, or flush it down the toilet. Real worm tea really is a great fertilizer – put a couple of handfuls of worm casts in a bucket of water (preferably rainwater), plus a spoonful or two of molasses if you have it, stir, and leave overnight, preferably longer. Stir it often, or, better, use a fish tank aerator with an air-stone to oxygenate it, and stir it often as well. Use it quickly
or it will go rotten.
This information above is what I do and have written about before here. I like simple. The sock tied off in a pail and a stick to stir it works for me. I am sure it will work just as well for you when you make your first batch of worm tea. Do shake it up and use it within 24 to 48 hours. Shake before each use and uncap it, if you have capped it in a bottle, this will get those microbes moving and doing what they do best: help our gardens to flourish..
Now that you understand the process, you can probably understand why worm tea, or at least in some circles has received a bad reputation. Do not be persuaded to forgo using worm tea, as it is terrific in the garden and on your houseplants. I urge you to do the process the simple way, for your best results.
- There is a right and a wrong way to make worm tea.
- Fix bin problems as soon as you notice them.
- Use the correct method of making and using your worm tea in a timely fashion.
- Enjoy your worms. They have much to teach you.