How Much Dry Organic Fertilizer To Use?

I'm slowly making the transition to growing organically, but have some confusion around dry mix organic fertilizers.

Up until this point I have been using general hydro flora series nutrients, feeding once per week. The plants are in sunshine mix #4, in 5 gallon pots, outside.

Now that I want to simplify things, and avoid having to constantly mix fertilizers I have chosen these two organic dry mix fertilizers, as they are local, and they contain a nice bevy of organic nutrient sources, and seem very complete.

For veg http://www.gaiagreen.com/products/product_detail.asp?ID=7

For bloom http://www.gaiagreen.com/products/product_detail.asp?ID=10

What I want to be able to do is just mix up the correct amount of these fertilizers in my soil, and then just add water for the majority of the grow. I don't mind adding in some compost tea or other organic liquid fertilizers near the end, but I just don't want to have to add anything during veg, and the first four to six weeks of bloom - just water.

From what I understand, organic fertilizers such as these are ''activated'' once they are wetted down, and the bacteria start going to work. This results in a steady slow release of nutrients, as opposed to the "nute-bomb" of chemical fertilizers which are available all at once, which are then used by the plant, and the excess washed away during subsequent waterings. (please correct me if I'm wrong here).

What I don't understand is how to know when you need to add more fertilizer, and how much to start with in the beginning.

I'm hesitant to just simply go by the dosage instructions the company lists on their website, as I'm not sure if this is too much or too little for cannabis.

I was hoping someone with a good knowledge of organic fertilizers could tell me the appropriate amount I should be mixing into my soil. Organic fertilizers like this are so much milder than chemical nutes (4-4-4 compared to 20-20-20 that I was using before.) so I really have no idea how much they should be fed as I am used to using hydroponic nutes with detailed feeding schedules already laid out for me.

The way I grow my plants is by starting seeds in small cups of just sunshine mix#4 , and once they are old enough for their first feeding, I transfer then into 1 gallon pots full of 'veg' soil. I veg them for 8-10 weeks, and then transfer them into 5 gallon pots full of 'bloom soil'.

So in summary, how much of the above mentioned nutes should I be adding to my veg soil, and my bloom soil respectively? I think the website says about 4 tablespoons of nutes per gallon of soil, well mixed in, but would like to hear other opinions. However, another important question I have is regarding the length of time the nutes are good for. The packing states to top-dress the soil monthly, but wouldt it be better to just add more in the beginning when you can mix it into the soil instead of top dressing? For instance, wouldn't I just double the dosage if I was planning on keeping the plants in veg for two months (and triple it if I was vegging for three). Or would this just burn the plants? I have heard lots of people say that it's hard to burn the plants with organic dry mixed nutes because they are slowly released.

REally confused on this topic, and would really appreciate your opinions if you have experience with organic soil nutrients.

Thanks so much for any advice you can offer

i use Gaiagreen products and love them.

you will get a much better flavor using single mix fertalizers....but you can use the pre-mix and get away with it. 200 ML's is good for around 2~ months (give or take 2 weeks) using the pre-mixed stuff.

this is my personal recipe, all my buds taste super fruity. (mostly gaiagreen):

200 ML N bat guano
200 ML P Seabird Guano
300 ML glacial rock dust
300 ML greensand
5 cups worm castings
1 cup dolomite lime
20 gallons of soil (roots organic or sunshine mix)
5 gallons perlite

GaiaGreen sells everything other than the castings, lime soil and perlite.

P.S: im hardcore like subcool when it comes to organics, if you have any questions just throw me a line

This is excellent, thank you so much. Really glad to hear you are using these products with good results. I finally just got fed up with constantly mixing nutes, and then playing this back and forth game of over-feeding, and then getting gun-shy and underfeeding. It really becomes a pain in the ass, and I've always wanted to go organic anyway. I'll have no problem locating all of the ingredients you mentioned, I've seen them all locally.

Few quick questions for you...

1) How much does this recipe make in terms of gallons of soil?

2) Does this take you right from start to finish, or do you find you need to supplement with additional feedings at any point during your grow?

3) Is that 200ml of the pre-mixed per gallon? or per 5 gallon?

4) I'll probably stick to sunshine mix as my base. If I do this, do I need to increase the amounts of the ingredients at all to make up for the lack of food in the sunshine mix? (I've never seen roots soil around here)

Thanks for your time, this is a great help.

#1 my recipe makes about 160 L or about 45 G of soil (the perlite makes it fluff up, ALOT) DO NOT pack the soil down at all. you want it as fluffy as possible.
#2 it can take you from start to finish. its best to suppliment feedings with compost tea. an organic tea made from guano, castings, and kelp extract work best
#3 200 ML per 5 Gallons. sorry about not specifying.

#4 sunshine mix is good but it can benefit from added Gypsum. peat on its own is very low in magnesium and calcium. you should be able to pick gypsum up anywhere u can buy gaiagreen products. just ask for it if you cant find it

Tea recipe:
1/2 cup castings
15 ML high N guano
15 ML high P guano

15 ML kelp extract
30 ML molassis

put dry ingredients in a cheese cloth and suspend in the liquid. make sure the liquid ingrediants are well mixed.
put the air bubbler directly under the suspended cheese cloth. let tea sit for 3 days. stir once per day.

when nearing the end of flowering stop adding the high N fertalizer.

Great, thank you.

How often are you applying the tea? Once every couple of weeks? Just straight into the soil, or do you dilute it down at all? (I guess I should ask how much water you are brewing the tea in as well)

And is the gypsum a better source of cal and mag than the lime?

Thanks again

i use 10% tea every watering. less is more when they have a constant supply of nutrients.

with organics you dont have to worry about salt build up so you dont have to flush the plants, or worry as much about burning them.

use the Gypsum along with the lime. there is a trace amount of cal / Mag in lime but the Gypsum provides Calcium and Sulfur (not magnesium, i was mistaken earlier)

brew the tea in batches of 5 gallons. that way it doesnt go bad before its fully used. u usualy throw it out (into the outdoor gardens ) after about 3-4 weeks.

Great, this is excellent information, I'll start on this tomorrow.

In your recipe you've got 15 ml each of high nitrogen guano, and high phos guano. What I found today was Bat guano at 0-15-1, and seabird guano at 13-12-3.

Are these the two products you mean? It seems that the seabird guano is really high in phos in addition to nitrogen, so I just wanted to double check that is the type you are meaning. There is also fishbone meal at 4-22-1 in case that would be a better alternative.

Thanks.

o use 12-2-7 bat guano, Gaiagreen stopped selling the bat guano a while ago it seems (checked their site). but Rubicon Organic has 10/3/1 that will work fine, if you can get rubicon organic products.

the seabird guano i use is 0-15-1.

looking at their "new product lineup" i would say use the Blood and Bone + , the all purpose , Power bloom and the 13/12-3 Guano.

your going to want to pick up Kelp extract from somewhere. i suggest rubicon organic, once you start using kelp you will never stop.

Sunleaves carries organic guano, its what I use.

OK Corbat, did some shopping today, and here is what I've got in my arsenal...

9 Large Bags of Organic Potting Soil (some local brand)
40lbs of Worm Castings
1L Dutch Treat Liquid Kelp (0.1-0.1- 0.5)
2.2kg Gaia Green Power Bloom Blend (2-8-4)
2.2kg Gaia Green All Purpose Blend (4-4-4)
2.2kg Gaia Green Bat Guano (0-15-1)
2.2kg Gaia Green Fishbone Meal (4-22-1)
2.2kg Gaia Green Blood Meal (12-0-0)
2.2kg Gaia Green Rock Phosphate (0-3-0)
2.2kg Gaia Green Greensand (trace minerals)
2.2kg Dolomite Lime
2.2kg Epsom Salts
1 Massive Bag of Perlite

I'm trying to calculate a proper blend, but struggling a little. Just can't figure out the proper ratios.

I don't want it to be so hot so that it will burn the girls, but I also don't want to go too weak that it won't take me all the way through flowering.

Don't mean to trouble you too much, but maybe you could have a look at my ingredients and offer a suggested mix. And let me know if there is anything else I should add.

I think I probably still need to add some beneficial bacteria, and perhaps some gypsum as you stated before. Not too sure what the organic potting soil has in it - it was on sale super cheap because it's the end of the season, it was local, and I figured it was better than sunshine mix because it is humus based, and not peat.

Appreciate any advice you can offer. Thank you kindly brother.

take a 5 gallon bucket and use that to measure. if you dont have one use the largest pot you have, figure out how many gallons it holds and use that to measure the soil and perlite.

tarps make life VERY easy when mixing soil. this is something i learned from subcool. pick up something like this before you start and life will be much easier. $20 goes a LONG way. http://www.walmart.com/ip/Heavy-Duty-Brown-and-Tan-Tarp-10-x-16/16889156

Soil:
20 gallons soil
5 gallons perlite
5 cups worm castings
150 ML Bat Guano
150 ML Fish bone meal
300 ML rock phosphate
300 ML Green Sand
400 ML Blood Meal
250 ML Dolomite lime
250 ML Epsom salts

Tea:
5 gallons water
30 ML Kelp
30 ML rock Phosphate
1/2 cup worm castings.

Top dress with All purpose in Veg, and Power Bloom in Flowering. 50 ML / gallon of soil

if your plants are fertilizer sensitive i would use 75%.
DO NOT add any more than this. i;ve worked with Gaia Green for a long time, it will start to burn if you add more......

I think I probably still need to add some beneficial bacteria, and perhaps some gypsum as you stated before.

Click to expand...

the tea uses worm castings to make the bacteria. just use the tea while bubles are forming on the surface.
the Epsom salts are BETTER than Gypsum and the All purpose has Gypsum in it

You are a scholar and a gentleman. Thanks buddy.

I've got 5 gallon pots, so that should be no problem to measure out. My father in law has got a cement mixer, so that will take care of the mixing duties.

I'm really excited to try this soil out, should make life a lot easier. And not to mention, the end product will be of far better quality than I'm used to with chems.

Mixing went well today, and I've got the tea started as well.

Do I need to let this soil mix cook like sub cools, or can it be used straight away?

I was thinking I could dump some of the tea into the soil mix to inoculate it with the beneficial bacteria, and let it bake for a few weeks if need be.

Also, when you say use 75% for sensitive plants, do you mean fill the pots 75% with this mix, and then the remaining 25% just the organic potting soil?

Thanks for the clarification.

its best to let it cook for 10-14 days to activate the Rock Phosphate and Greensand, but it CAN be used straight away.

wait untill after the transplant to add more bacteria. the 5 cups of worm castings per batch adds enough to inoculate the soil mix with bacteria. if there is to much bacteria in the soil before planting it can be bad for the roots.

75% means mix it 75/25 with soil that has no nutrients. it will make it easier on the root system. the best way is to follow subcools transplanting method, dig a large well in the supersoil and "lace" it with soil that has no addatives. transplant the rooted plant into the hole and fill with more weak soil. this way the roots dont come directly into contact with the supersoil, and it stops root burn.

allways happy to help when it comes to organics

P.S:the best way to inoculate the soil with bacteria is after the transplant. feed it with 80% water 20% tea and that will ensure the bacteria is all there.

Corbat420 said:

the best way is to follow subcools transplanting method, dig a large well in the supersoil and "lace" it with soil that has no addatives. transplant the rooted plant into the hole and fill with more weak soil. this way the roots dont come directly into contact with the supersoil, and it stops root burn.

Click to expand...

So basically you mean having a small layer of potting soil between the transplant and the supersoil as a buffer?

exactly

roots in organic soil will "explore" the soil untill they hot the pockets of nutrients they need. with well mixed soil and a good layer between the soil and the root ball the roots will simpley go to the supersoil when they want it

Question on the tea. I've read that teas must be used within a couple days of brewing otherwise they go anaerobic and become harmful to the plants. How do you keep yours fresh for 3-4 weeks?

Also, do you replace the same volume of water into the tea that you remove each time? For example, if you take out a cup of tea, do you replace a cup of water back into the brew? This would cause it to become progressively more dilute after each use, correct?

i dont keep it fresh. i use it for a full 2 weeks and have never seen any harmful effects on the plants. the Molasses helps ferment the tea, but since there is Oxygen present in the mixture no alcohol is formed... the bacteria simpley break teh sugers down into an even more usable form.

No. never dilute the tea directly. use measured instruments (i use 2L bottles with lines marked on them....500 ML, 1L, 1.5L) this way you know how much your using. dilute 250 ML of tea to 1000 ML of water for the first shot, and move up to 500 ML / 1.5L of water when the plants are large enough.

Thanks mate, appreciate your input.