Harvard University compost tea recipe

[fruitnoob]

Has anyone tried this recipe from Harvard for fruit trees? If yes, how did it help or hurt your trees? https://green.harvard.edu/tools-resources/how/make-your-own-compost-tea

[pagnr]

I have used commercial products in Australia with a similar base of ingredients.
It comes as a concentrate, with low biological activity until you dilute it.
Once you make up a tank mix it becomes active, as the concentrate suppresses activity.
I mainly used it on container plants, no problems. But I didn't brew it.
Later I switched to the dry fertiliser version of the same thing.

I did have problems when I added extra microbes to the mix and brewed those.
Basically I got a population of unusual microbes in my pots, that I have never seen before.
I would watch out for too much microbe activity.
You may not need to brew the mix at all, or as much as they say,  it should also stimulate the soil flora already there.

You may want to also think about what you use it on, i.e. maybe not directly on leafy greens or vegetables you eat raw, or just prior to fruit harvest.
Also Composts are pretty variable in their composition and maturation. The microbes are going to be variable in different composts, and at different stages.
Most of the other ingredients are pretty standardised, i.e. Kelp, Humates, Molasses etc.
There are various brands of these, some better than others.
There were problems with Fish fertiliser being sprayed on Citrus for juicing, and microbes being carried into the juice process line.
(Well that was the story.)
I did use fish fertiliser in my fertigation, along with the kelp, humates etc but used the tank within one day and didn't let it brew.
The oils in fish fertiliser might be a problem for some plants, and if applied too strong, same as any oil spray.
The vegetable oil and the flour in the brew mix might be additional microbe food ?

To sum up, I used most of the same ingredients as liquid fertiliser drench, not sprayed on foliage, and didn't brew it.

[fruitnoob]

@pagnr: Thanks. I am thinking about brewing the compost for 24 hours and pour it on the ground until I know it is safe enough to spray on the leaves of my fruit trees.

[achetadomestica]

I read a pretty good paper written on compost tea vs compost.
In the study soil samples were analyzed. The findings were that compost tea
does not provide a plant more nutrients then compost that has been mixed in
to the soil. I add a circle of fresh mulch 2-3 times a year around all my trees.
I also continue to add coffee grounds and other organic materials around the trees.
This year I have been adding cricket frass around most of my trees on the first of
every month. I have been at this location for over 10 years. If you look under the
canopies of my trees the top 3-6" is black dirt and then the sand is black for 6 more
inches. I started with pure white sand. But in the past 10 years I have added compost tea,
fish emulsion, mollasses, pine needles, oak leaves, and plenty more. It seems like every time
I read somehting I try it. I have never noticed a huge result from any new fertilizer,
or foliar spray. Allot of times I switch to another idea before I really even see the results
of the last new additive. Most of these studies are done on deficient plants then you see
amazing differences. I do get bored and continue to try new things.
One good example in my yard this year are my mulberry trees. They are on the North side
of my house and I don't fertilize or water them. This year I started adding cricket frass once
a month and all the trees are showing huge growth like I have never seen. If I would have
used compost tea or 8-4-8 Diamond R synthetic fertlizer I bet the mulberrys would be responding
the same way.

[fruitnoob]

@ achetadomestica: it is impressive how you built up your soil. My soil is also white sand; I have mulch on top of it and have not seen much improvement yet after 10 months.
I’ve invested in the tools and materials to make compost tea. Now I am not sure anymore. lol

[pagnr]

"I read a pretty good paper written on compost tea vs compost.
In the study soil samples were analyzed. The findings were that compost tea
does not provide a plant more nutrients then compost that has been mixed into the soil."

Compost tea is probably as much about increasing biological activity as providing nutrients.
Maybe also making compost go further ?
Composts have been found to be repressive of soil pathogens, and providing nutrients in biological active forms.
Also soil Carbon was not on the soil nutrient measuring radar as much until fairly recently.
Test measuring soil nutrients may not cover these aspects ?
Some people have been on about soil Carbon / Biological activity for decades. It has only become more widely accepted here recently.

My soil is also white sand; I have mulch on top of it.
I’ve invested in the tools and materials to make compost tea. Now I am not sure anymore. lol

Sounds like a good area for giving it a try ? Maybe something like in ground hydroponics with a sand based soil.
Probably the more actual compost and organic matter you add the better.
Compost tea might help in maintaining the levels.
My pot mixes were sand coir based.

[Fruit Jungle]

@ achetadomestica: it is impressive how you built up your soil. My soil is also white sand; I have mulch on top of it and have not seen much improvement yet after 10 months.
I’ve invested in the tools and materials to make compost tea. Now I am not sure anymore. lol

10 months isn't too long. Is it bone dry? That will slow things. How much mulch are you adding, I would say you need 2-3 feet of mulch and 2 years to see good results, as long as things stay moist.

Of course, mulch is just one way to add carbon to the soil, the living root and it's exudates is the superior way to add carbon to soil.

[fruitnoob]

@Fruit Jungle: I have about 3 inches of mulch. I can see the mulch getting degraded but it’s still sitting on top of the soil. Hopefully it’ll work into the soil over time.
I’ll give the compost tea a try to see if it’ll make any difference. Thanks.

[pagnr]

Fraser Island, off the coast of Queensland. Noted as a Sand Island, growing extensive rainforest.
https://www.fraserisland.net/fraser-island-formation/fraser-island-rainforest
There are other brews you could investigate.
Enteric microbes, Comphrey, Other green waste like weeds/lawn clippings ( not from weed sprayed turf ). Kelp, if you live near the ocean.