What's new
  • Happy Birthday ICMag! Been 20 years since Gypsy Nirvana created the forum! We are celebrating with a 4/20 Giveaway and by launching a new Patreon tier called "420club". You can read more here.
  • Important notice: ICMag's T.O.U. has been updated. Please review it here. For your convenience, it is also available in the main forum menu, under 'Quick Links"!

Replacing Blood meal with Alfalfa meal for the main source of nitrogen

Dr.RedWhite

Active member
I use 1/2 cup of blood meal in 1 cubic foot of soil for it's nitrogen content. I would like to use Alfalfa meal instead. Does anyone know how much Alfalfa meal I should use in a Cubic foot of soil? The numbers attributed to Blood meal range from 11 to 14 of N. Is that a percentage of the total nitrogen in Blood meal? Alfalfa is generally rated as a 3 for it's N content. So roughly does that mean I need to use 2 cups of Alfalfa to get what comes from 1/2 cup of Blood meal?
 

flylowgethigh

Non-growing Lurker
ICMag Donor
I use it as one of the ingredients for tea.

edit: Brewing some now. Some BAS top dress, EWC, alfalfa, tiny bit of chicken poop.
 
Last edited:

40degsouth

Well-known member
E7186B74-14C1-44B1-A4ED-B4B98E400DE1.jpeg
2A070760-5E8E-481D-B54B-25688CB10D22.jpeg
Here’s a bit of information from Steve Soloman.
Cheers,
40
 

moose eater

Well-known member
The N in blood meal typically runs about 13 points, with -0- P and -0- K; alfalfa meal is around a 2.5-0.1-2.5 for N-P-K array.

Blood meal is relatively fast-acting N, if I recall correctly, whereas alfalfa meal takes a fair bit longer (*years ago here, Doc Tim and others posted organic amendment release rates/times).

You're truly dealing with apples and oranges, and unless you use a shit-ton of alfalfa meal, let your mix 'cook' for a lengthy period of time, and maybe even cut back on your other source(s) of K, I think it's apt to send you down a rabbit hole or 2.

But to be more concise, all of that outa' the way, your alfalfa meal has about 1/5 the N of your blood meal...

On a positive note, I believe there's less chance of pathogens or attracting insect pests with alfalfa meal.

Were it me, I wouldn't do it. But I'm stuck in my ways; sometimes for better, & sometimes for worse.
 

Great outdoors

Active member
Alfalfa meal is too hot to be able to get enough in as a sole nitrogen source. If you add it a good couple months before planting you can get the heat out, but you will still struggle to get enough nitrogen for a sole source.
A good option is soybean meal. It's 8-2-2 and a medium release. Hard to burn plants with but if you overuse you could have some big leafy monsters.
Both can be used anywhere from a half to a full cup per cubic foot. Between the two, you only really need a good phosphorus, calcium addition, and a little more potassium to even things up.
 

flylowgethigh

Non-growing Lurker
ICMag Donor
I just top watered in an alfalfa / EWC/ BAS Top Dress /1 TBSP chicken shit tea with a little fish oil added onto my 2nd run plant's soil. That should add some N. This time the plants didn't "pray", but this is also week 5 flower.
 

St. Phatty

Active member
About 13 years ago one of my neighbors at a community garden in Sonoma County spread alfalfa all over his 15 foot square plot.

He told me about the wonders of Alfalfa.

And a week later he committed suicide.

Never got the whole story but Jeez. I adopted some of his tomatoes, and for sure, when I looked under the alfalfa, all sorts of animals. Salamanders etc.
 

flylowgethigh

Non-growing Lurker
ICMag Donor
I'm thinking this would be a better fit. Or I could go along with using Alfalfa as part of the teas and don't fix what isn't broke.

I use that stuff when I mix up and amend the soil. Coots said a lot of good about it, and it supposedly also helps with the IPM.

I gotta quit with the chicken sh*t, and feeding/watering all the strains the same. The AK47 didn't like it, the Strawberry sisters love it.
 

Dr.RedWhite

Active member
Well a year later I return. I decided to use Medina poultry manure which is processed and stable. I ended up using 1 1/2 tablespoons per gallon of soil, actually mixing 3 tablespoons in two gallons of soil already amended with bone meal 1 cup and wood ash at 1/2 cup, 1/4 cup epsoms salt, 4 cups of floor sweep for the silica, 4 cups worm castings to end up with a bit more than 6 gallons of soil. Sunshine all purpose as the base. This worked really well overall with a tea or two throughout flower.
 

nono_fr

Active member
Hello

I have dry alfafa with instruction too make tea and more ( but I never use in soil, just tea ... )

DSCF0012.JPG


translation :

Perfect for oxygenated compost teas. " grow "
ideal for mulching (5 cm thick around each plant, in the ground or in a pot).

Dosage: 25g/10L of aerated compost tea, 100g/10L of liquid manure, 250g/m2 in mulch. 100g dry = 1 kg fresh
:clover:
 

St. Phatty

Active member
Plants seem to place a big difference between Soil Nitrogen and Atmosphere Nitrogen.

Given that the atmosphere is about 80% Nitrogen - don't they get some of their nitrogen from the air ?
 

RandyCalifornia

Well endowed member
Veteran
In my experience, alfalfa breaks down pretty quick. If you sprinkle a little at a time on the surface and top feed you get tea every time you water as it's breaking down. The worms eat the bacteria and take it down to feed down in the roots and aerate the soil .
If you amend soil and only water it breaks down too fast you get huge overgrow veg with hungry at flower time plant
 

Chunkypigs

passing the gas
Veteran
I use a 50# bag in my patch every year then suicide soon after overgrown veg.

outs 9-16-21.JPG


I never get to see who harvests all my weed 'cause I'm dead from all that alfalfa...
deader than a fly stuck to OG Kush.

OG Lover.JPG


my hungry flowers also suicide, every one of them.

DSC_0808 copy.JPG


sadness filled the air. at least 2 cups full.
 

Three Berries

Active member
Plants seem to place a big difference between Soil Nitrogen and Atmosphere Nitrogen.

Given that the atmosphere is about 80% Nitrogen - don't they get some of their nitrogen from the air ?
N2 as it is in the air is pretty stable. Most N a plant gets from the air is from rain water as the ultra pure water falling thought the air and if your lucky some lightning will bust up the N2 and make H+ acids that break down and plants can use. Same with CO2 but to a lesser extent.

Decomposed organic matter also has some but it's mostly from the organism's waste that decomposed it. I use fresh wood chip mulch around trees. If i don't dose them with some high nitrogen fertilizer all the plants will suffer where the mulch covers the roots.
 
Last edited:

CrushnYuba

Well-known member
I don't think any plants use nitrogin from the air. I could be wrong. Pot definitely doesn't. There's different forms of nitrogin. I'm the gas state it's not usable. The ecosystem works on nitrogin cycling. Plants legumes like alfalfa can grow in soil with no nitrogin but they themselves don't utilize the n in the air. There's is bacteria that grows in the roots that does it. That's why farmers grow alfalfa as a cover crop.
I will second what greatoutdoors said about alfalfa being too hot to use as a primary n source. I think a good amount gets lost when it gets broken down from organic n to useable. Alfalfa seems like it's mostly good for bacterial life and getting stuff cooking. It's great to add to a mix to get it to heat up and decompose. People use it in compost piles to speed up decomposition.
I always use it. The amount depends on how long i have for it to sit. But i don't even count how much n it adds. It's not much. Not everything breaker down with the same efficiency.
It has an almost perfect carbon to nitrogin ratio for hot composting
 
Top