Humic acid

[Tracydr]

Im building a new raised bed. Mostly composting aged, pulverized horse manure in place, along with crushed alfalfa hay, kitchen scraps, some clay, mixing in some sulpher and gypsum. I have some humic acid and I was wondering if it would be a good addition? How much should I add?
I'm adding water, topping with newspaper and straw, will let this heat up, cool down and then start planting.

[dice]

What kind of humic acid? Like a concentrated liquid? When I have used
that, I just added an ounce or tablespoon per gallon to the water that
I watered in seedlings with.

There is a dry product called "Micro Hume" that can be dissolved and
used with fertigation. There is also granular stuff that you can amend
your soil with:
http://www.groworganic.com/activate-50-lb.html
(I imagine that shipping on 50# would raise the price quite a bit, but
I do not know who would have it locally. You might be able to order it
from Crop Production Services and pick it up a week later or something.)

[Tracydr]

This is a dry, granular product labeled for use as a soil conditioner and compost activator. I purchased it at a local nursery, it wasn't real expensive.

[dice]

Per plant, it does not take much to get the benefits. I have never amended
a whole garden bed with it. Humus develops as the organic matter in your
beds decays, so you may not notice a big difference in a heavily amended
garden bed. Then again, growers in your area typically have high pH
soils, and raising the humic acid content would protect some nutrients
from combining with other compounds in the soil at high pH and
becoming insoluble.

It will not have any negative effects on the soil. It can only help or not
help (because your garden already has plenty of it from decaying
organic matter).

[Tracydr]

Thanks, dice. I'm giving it a try!

[habitat_gardener]

I've used this one
https://www.johnandbobs.com/product-details/
(the first one -- it used to be called John and Bob's Soil Optimizer). It was recommended by a local tomato grower to help plants survive in cooler temperatures. I've used about a tablespoon or a teaspoon per plant for the last couple years or so. I've had great harvests in cool summers when other people in the area said it was a bad tomato year, so it's either that or the handful of alfalfa in the hole or the liberal use of homemade compost or my rich, fluffy soil (after years of adding compost and mulch).

[dice]

Sometime in the late 1980s, I was out on this plot of flat land west of
Mt. Rainier with a couple of guys that were doing a "perk test" (to see
if the soil drains, etc). It was kind of open, second-growth forest with
a random mix of evergreens, alder, and maple on it, with not much
undergrowth. There was maybe six inches of humus on top of clay
and gravel subsoil.

The land developer that had the plots for sale had bulldozed a dirt road
into it from the nearest county highway, and along the edge of that dirt
road there was about a foot deep roll of humus that the bulldozer had
scraped off of the subsoil. This looked like nice stuff, so I borrowed a
garbage bag and shovel and filled it up.

I took it home and potted up houseplants and outdoor container plants
in the humus. By the end of the summer, they looked fabulous.