Take the 2-minute tour ×
Gardening & Landscaping Stack Exchange is a question and answer site for gardeners and landscapers. It's 100% free, no registration required.

As the title would suggest, I may or may not have given my kids e. coli by steeping a bag of what I thought was mushroom compost in a 35 gallon drum and watering my garden with it. (I know it was mushroom compost, I don't know how much manure was in it)

I don't believe I ever watered directly on the lettuce or kale leaves, but that's more than likely where they got it from. I wouldn't water directly on the leaves regardless.

What I did was take a burlap rice bag, filled it full of mushroom compost and steeped it (or rather just left it) attached to the lid of the drum and used that water.

The next year I tried making vegetarian compost tea using thistles, nobody got sick but that somehow left my drum even dirtier than using manure and would clog up the faucet on the drum.

Anyway, I'm just wondering what the proper setup is for manure tea (aka compost tea), should it be done in the shade? how fast should you use it? do you need to clean the barrel after using it? What is a good store-brand manure to use? How can you be absolutely sure the manure is fermented before using it?

share|improve this question
1  
@wax eagle, thanks for the bump I think I would have missed Mike's awesome answer without it. But I believe compost tea refers to the runoff from a compost bin, whereas manure tea is actually manure steeped in water. –  Peter Turner Aug 16 '11 at 13:17
1  
Compost tea is compost steeped in water and aerated (see Mike's answer). You are thinking of Compost leachate. I'm thinking about posting a question on each of these. Going to raise it on chat if you want to come talk about it there. –  wax eagle Aug 16 '11 at 13:26
add comment

2 Answers

up vote 9 down vote accepted

First, let me say I'm no expert when it comes to compost tea ie I don't know the (full) scientific in's and out's of it.

Second, I've only been making compost tea for 2 years now. It's easy, it's fun (my oldest son and kids in our street think I'm some kind of mad scientist, while my youngest son just wants to drink it), and I've personally noticed benefits in my garden from using it on a regular bases. The below quote comes from this answer here on SE.

  • I make 5 gallons of compost tea each week (from late Spring to earlier Autumn "Fall") and apply the 5 gallon batch to the front garden one week, then the following week apply a new fresh 5 gallon batch to the back garden. I repeat that cycle for the period given previously. I have been doing this for 2 years now, and without question I have noticed a massive increase in worm activity eg lots of worm castings on the surface of the soil.

    • I spread the 5 gallons of Compost Tea via a watering-can over approx 1800ft² (170m²). Lawn area is about the same front & back for me. So one week the front lawn gets treated, then the following week the back lawn gets treated, repeat, repeat...

Rightly or wrongly, below is the method I've used for the past 2 years (with success) and will continue to use, or at least until I'm told I am doing it wrong.

Stuff you need:

  • 5 gallon (19 Litre) bucket - bought new and is used for nothing else.

  • Stirring stick (used for nothing else) - basically a clean, thin but sturdy piece of wood, about 2 to 3 feet (600 to 900mm) long.

  • Molasses "Unsulfured" - personally I spend a little bit more and go with an organic product.

  • Compost (I use my own homemade compost) - can be homemade or bought, the important thing is, it's "good" quality, aged compost.

  • Earthworm Castings (I buy locally) or a product like, Dr. Earth Organic Planting Mix.

  • Old stockings or tights, or buy the cheapest ones you can find.

  • Watering can - do not use one that you put any kind of chemicals in.

  • Funnel (used for nothing else) - large enough to allow easy transfer of the (finished) compost tea from the 5 gallon bucket to the watering can.

  • Materials bought from aquarium shop/outlet:

    • Aquarium pump - powerful enough to run the system you decide to set-up. I think the smallest pump my local aquarium shop sold was rated at "20 or 30 gallons" (76 or 114 Litre), but for only $2 to $3 more I decided to go with a slightly more powerful "40 gallon (151 Litre) pump".

    • Gang valve - 3 way.

    • 3 Bubblers.

    • 10 feet (3000mm) of tubing.

    • A reusable (fine) netted bag - after going through a few pairs of cheap stockings/tights, seeing as they're only good for one brewing process, I figured there must be a better way. I spoke with my local aquarium shop about my "peculiar" requirements, in fact they were fascinated by what I was doing, they suggested and got hold of a "reusable (fine) netted bag". I've now been using that bag for the past 18 months.

Below: 40 gallon aquarium pump, gang valve - 3 way, bubblers (4 pack) and tubing. (click image to enlarge)

Aquarium pump, 3-way gang valve, bubblers & tubing

Below: Organic Molasses "Unsulfured". (click image to enlarge)

Organic Molasses "Unsulfured"

How I make compost tea (for use on my lawn, but I will occasionally give a plant a small amount, if it looks like it could do with a little pick me up):

  • I've set-up a small area in my garage where I make (brew) my compost tea. It's out of direct sunlight and protected from other outdoor elements eg Rain.

    • Keeping the brewing process out of direct sunlight will prevent it from heating up too much. Too much heat can cause the (beneficial) organisms that you're trying to stimulate (wake up, make perform their magic) to slow down.

    • Keeping the brewing process protected from other outdoor elements greatly decreases the possibility of "foreign" bodies, elements, etc from entering the compost brew.

    • Of course the brewing process can easily be performed outdoors if located in a shady area and some kind of enclosed brewing system is set-up.

  • Connect up the aquarium pump, 3-way gang valve, 3 bubblers and tubing (see photo below). When doing this, ensure each bubbler is connected to tubing that is long enough to reach the bottom of the 5 gallon (19 Litre) bucket - 2ft (600mm) of tubing should be long enough.

  • On a Wednesday morning fill the 5 gallon (19 Litre) bucket with 4 to 4½ gallons (15 to 17 Litre) of cold water.

  • Place the 3 bubblers into the water so that they sit at the bottom of the bucket, then turn on the pump. I let this run for 24 hours. Why? The air circulating through the water will remove (blow off) the chlorine, and you want that to occur so there's no chlorine left in the water to possibly effect (harm, kill) the beneficial organisms you add later.

  • On a Thursday morning mix together ½ gallon (2 Litre) of sieved compost and ½ gallon (2 Litre) of sieved earthworm castings.

    • Place that mixture into the reusable (fine) netted bag ie Basically make a giant tea-bag.

    • Then add the bag to the (chlorine free) water in the bucket.

  • Measure out 1fl oz (30ml) of Molasses "Unsulfured".

    • Pour that into the (chlorine free) water in the bucket.
  • With the stirring stick, give the mixture a good stir.

    • Then for the next 2 to 3 days go out there 3 or 4 times a day and give it a "quick" stir.
  • Saturday, after 2 days of brewing (minimum) or Sunday, after 3 days of brewing (considered the perfect brewing period for the recipe I use) go out there and turn off the pump.

    • Remove the 3-way gang valve, bubblers, bag from the bucket, so you're just left with the bucket and its freshly brewed contents ie Compost tea.

    • Immediately transfer the compost tea to the watering can with the help of the funnel. The below point explains why it's best to use the compost tea immediately or within 1 hour to ensure maximum benefits are reaped from the brewing process.

    • Compost tea doesn't store well, mainly because without air being constantly feed through it, it will become anaerobic and eventually start to smell. Also the (beneficial) organisms will become inactive due to lack of food after 3 days of brewing, they've pretty much used up the 1fl oz (30ml) of Molasses "Unsulfured" originally added for their benefit.

    • With the watering can in hand, I slowly walk my lawn while allowing a small amount of compost tea to flow onto the grass as I walk in a pattern that ensures I cover my lawn the best I can.

    • Once all the compost tea has been poured onto my lawn (1 week the front garden, the following week the back garden, then repeat the cycle), I get the bag with the compost and earthworm castings mixture and place that mixture around any plants in my garden that look like they could do with a little pick me up.

    • Finally, clean up everything with clean cold water.

  • Then the following Wednesday (after 2 or 3 days rest) I start the whole process allover again.

Below: Aerating water in a 5 gallon (19 Litre) bucket to remove chlorine, via 3-way gang valve, 3 bubblers and tubing connected to a aquarium pump. (click image to enlarge)

Aerating water in a bucket

Below: Immediately after the reusable (fine) netted bag (containing the compost & earthworm castings mixture) and Molasses "Unsulfured" have been added to the aerated water in the bucket. (click image to enlarge)

Brewing Compost Tea

Below: After 2 to 3 days of brewing (& the occasional stir) the compost tea is ready for the garden. (click image to enlarge)

Brewing Compost Tea

Notes:

  • "Good" quality compost doesn't really smell, apart from having a very slight earthy smell.

  • Earthworm castings also don't really smell, apart from having a very slight earthy smell.

  • Compost tea doesn't (shouldn't) really smell, apart from a having very slight, sweet, earthy smell.

  • If anyone one of the above had a strong smell, I would be concerned there is something not quite right and wouldn't proceed with using them.

  • Before I started making my own compost tea, I read up a lot about it (there are many ways to make compost tea), watched it being made and used on a number of TV gardening shows, etc In the end the advice I followed (rightly or wrongly), mainly because it made sense to me and "generally" reflected what I'd read, seen and heard, was:


Hope the above helps, please let me know if I've missed anything or need to explain anything further. Good luck and happy brewing.

share|improve this answer
    
Wow! this totally beats the "crap in a sack" method I used! The one thing you might want to add is whether or not you should use it right away or if you can bottle it. And if you need to make it indoors or if you can make it outside (which I think my wife would appreciate) –  Peter Turner Aug 16 '11 at 13:14
    
@Peter Turner, do these 2 points from my above answer not cover the points you've raised in your above comment? 1) I've set-up a small area in my garage where I make (brew) my compost tea. It's out of direct sunlight and protected from other outdoor elements eg Rain. 2) Immediately transfer the compost tea to the watering can with the help of the funnel. –  Mike Perry Aug 16 '11 at 15:15
    
No, the answer is sufficient to not get anyone sick. I was just wondering what the absolute parameters are since I'm a lazy gardener. –  Peter Turner Aug 16 '11 at 15:26
1  
@Peter Turner, please refer to my revised answer. Hope it helps. –  Mike Perry Aug 16 '11 at 16:17
add comment

This page provides a good summary of technique and the following warning:

They also recommend that manures and manure teas not be applied to vegetables and fruit within 60 days of harvest and 120 days to harvest on root crops.

I personally wouldn't use store bought manure. I'd either get it from a source where I knew it was well composted, or do it myself.

Edit:

I've done some more research on this (important!) question.

Presence of Pathogens

This article (which is pretty technical) discusses compost production techniques. There are some references in there that mention certain techniques that will increase the likelihood of getting pathogens in your tea; it makes sense to avoid these. (It mainly sounds like you want to avoid adding "enhancements" to the tea, but you'd need to read the referenced articles for details.)

Compost (incl. Manure) Quality

This fact sheet from Cornell talks about compost production standards. Executive summary: unless you're dealing with human sewage (sludge) or using compost that is specifically regulated by the National Organic Program, it's essentially unregulated. (That fact sheet covers NY state; I suspect but am not sure that other states have similar situations.) Why it matters to you: you have no idea what was done to produce the stuff in the bags you buy.

This article gives you a feel for how much effort you can put into determining whether the end product of a composting process is useful.

Starting with a product that already has a high pathogen load seems like a recipe for disaster.

Tea Production Technique

From what I've seen in scanning the literature, there are various techniques in use for producing compost tea. I've seen people ranting (not hard science) that one technique is vastly better than another technique. I'm not bothering to link to any since I think I've seen arguments in both directions and it's impossible to tell who is right.

Some of the studies I've referred to elsewhere here talk about maintaining different temperatures. (They're all held at controlled temperatures, of course -- most home gardeners wouldn't bother.) It wasn't clear to me whether one temperature is better than another; there could be differences depending on what you're trying to do with the tea.

One of the major differences in production is the use of aeration. This basically involves putting a pond pump or something similar to get air into the tea. There are descriptions of systems you can set up with an aquarium pump for small scale production.

Benefits of Compost Tea

There is some scientific evidence that teas are effective at reducing disease pressure. This article refers to some other scientific publications (that I haven't located yet) about tea effectiveness at fighting disease.

But there are scientists cautioning the use of manure teas. It's not a miracle cure. As you discovered the hard way, there are risks too.

For home production in an uncontrolled setting, it may not be worth the risk. Personally, I like the idea that I could make manure tea and possibly reduce the chance of getting blight on my tomatoes. But I'm not sure that I can produce tea in a way that will really give me the outcome I'm looking for, and mitigate the risks.

Bottom Line

Unfortunately I haven't really answered your direct questions:

Anyway, I'm just wondering what the proper setup is for manure tea, should it be done in the shade? how fast should you use it? do you need to clean the barrel after using it? What is a good store-brand manure to use? How can you be absolutely sure the manure is fermented before using it?

  • There are different setups possible for tea, and it isn't clear that there is any one "proper" setup. The literature doesn't seem to have converged on a best way to do it.
  • I didn't see any mention of shelf-life...
  • Being scientific studies testing for pathogens etc, the studies I saw were sterilizing the barrel. It isn't clear that you need to go to this length.
  • See "quality" above regarding the difficulty in choosing a brand and knowing its quality.
share|improve this answer
    
120 days to harvest root crops!!! That precludes everything except maybe parsnips and rutabaga. –  Peter Turner Jun 13 '11 at 17:46
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.