Worm tea is worm castings which have been soaked in water and oxygenated. The extra oxygen causes a bloom of the good bacteria, plus the added benefit of nitrogen, phosphate, calcium, magnesium and potash.
The liquid that drains out of a worm composting bin is leachate. Leachate contains undissolved solids and some potentially harmful bacteria. However, it can be aerated as described below and used.
Some of the benefits of the tea include:
- a natural repellent for scale, mites, white flies, and aphids
- natural fungicide in soil and on plant surfaces
- increase in plant stem size and foliage
- acts as a soil conditioner
- will not burn plants
- creates healthy soil for healthy plants
- aides in the creation of colloidal humus
- grows healthier fruits and vegetables than those treated with chemical fertilizers
- improves water retention in soil
- reduces the amount of waste going to the landfill, because worms eat our garbage
How to Make Worm Tea
Tea can be purchased from an organic supplier or you can make it yourself.
To make your own tea, you will need:
- 5 gallon bucket
- tap water
- 3-5 handfuls of worm castings in a permeable bag, or not
- tablespoon or so of molasses
- aquarium air pump and bubbler
Instructions:
- fill the bucket 3/4 of the way with tap water
- insert the bubbler and let the water aerate for a couple of hours to remove chlorine
- add castings
- add molasses
- let bubble for another 24 hours
Your tea is now ready for use. Check out the video below for visual instructions.
Using Worm Tea
Since the tea is alive and full of microbes, it has a shelf life. The quicker you use it, the greater the benefit. It can always be re-aerated using the instructions above.
If your tea stinks, it has gone bad, and don’t use it.
The most common way to use the tea is to put it in a hand sprayer and spray your plants with it. You can even spray the lawn. Aerated tea will not burn your plants, and it helps repel certain insects.
Think of worm tea as a natural immune system booster for plants. It provides the good microorganisms and nutrients needed for plants and soil to repel insects and disease.
You can also water your plants with it. It’s great for seedlings since it provides nutrients but absolutely will not burn.
So have at it.
According to Bentley, at redwormcomposting.com, you can feed tea to your worms. Soak cardboard in the tea and then place in the worm bin. This gives the worms bacteria to feed on. Nice!
You can find out more about worm tea and worm composting at my sister site, Wormilicious.
{ 13 comments… read them below or add one }
if we keep the worm tea on the bottle for how long the microbia can life or the worm tea expired date?
It’s best to use worm tea as soon as possible. I would say within a week, but it is possible for the tea to go bad before then. If it smells bad don’t use it because the good bacteria have died and anaerobic ones have flourished.
After Years of successful Composting & producing VermiCast –& a few Months of successfully producing/applying VermiTea– I’m given to understand that Variations of the Components in VermiFood cause varying Reactions in Vegetable Plants, when the resultant VermiTea is applied.
What are the Components that will promote
the Vegetative Stage ||| the Flowering Stage
of Vegetables (Tomato, EggPlant, Legumes & RootCrops) and what Substances should be added to the VermiFood to achieve each of the above effects?
Many Thanks, Wolfgang
Wolfgang, I’m not really sure what components in the worm castings promote different stages of plant development beyond the common minerals such as potassium and phosphorus. It’s been my experience that worm tea very much promotes flowering, and in a very short amount of time, often a day or 2 later. Hope that helps.
I have a guinea pig. He has mites from the hay he eats. In your article, you stated that the tea repels or kills mites. Can worm tea be used to repel mites on a mammal?
Colette
Colette, I wouldn’t put worm tea on a guinea pig. I’d try diatomacheous earth to control the mites. Or I’d switch feeds!
Thank you I do have d earth should I sprinkle it on him like a salt shaker?
Colette
Colette, I’m not an expert on these things, but sprinkling the DE on your guinea pig and rubbing it in sounds like a good plan.
I find it interesting that dechlorinated water is recommended for brewing but nothing is said about just watering the crop. Since I make my own tea I felt the hole garden should be chlorine free all the time. This will sustain the great investment in your soil. Since I could not find an affordable filter with out KDF. I had my own made! check me out at gardenfreshfilter.com
Can I use the “tea” in the bottom of my worm castings for the same effect you’ve described in the tea brew? Someone told me it could be applied at a 1-10 ratio (1 part worm tea/10parts water).
Anthony, technically the liquid in the bin is lechate, not worm tea. Some say it is dangerous, others say not. I figure if it doesn’t smell bad, it’s probably okay. And you can use it straight or diluted maybe 1:2 or 1:3. 1:10 seems a little thin. More at the worm blog.
Also, sounds like I shouldn’t be holding the tea out over a period of time as that would kill the good bcteria?
Definitely do not hold the tea over. That’s one of it’s biggest drawbacks. You need to use it right away, because as soon as you pull the air off, the microbes start dying.