fertilizer When to fertilize potting soil?

Edmick

Edmick

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I started all my seed in potting soil in seed starting trays and transplanted them into 4 inch nursery pots once they developed their first leaves. They've been in the 4 inch nursery pots for about 3 weeks now but when should i start adding fertilizer? I usually use fox farms ocean but ive been using scotts hyponex due to cost constraints. I also plan on using only compost tea to fertilize. Any input is appreciated. Thank you.
 
Is that Hyponex a 'soil' of some sort, or just a mulch?
If a mulch, it will probably lack nutes for the plants, and you'd want to start fertilizing least a little fairly soon. 
 
I have zero experience with 'tea' of any sort, so can't suggest...
 
there are a lot of variables that need to be considered to answer that question accurately.  Most of them are dependent on whats in your "soil".  I grow organically so I add a small amount of granulated fertilizer (I'm an Espoma fanboy) into my soil mix and that's enough to get them through the 2-3 month inside before planting out.  Remember a plant synthesizes 96-98% of its self from light air and water so it doesn't need a ton of help.  Inside your fertilizer needs will be dependent on growth rate so soil consistency, air temp, humidity, species all need to be taken into account.  The easy answer is every other watering give them 1/2 to 2/3 of what the bottle says. If the leaf tips start to yellow its too much and flush the soil every few weeks to wash away salt build-up. Compost tea doesn't supply nutrients it supplies microbes which make existing nutrients bio-available to the plants which if growing outdoors can be enough provided you have rich soil.  For liquid fertilizer I really like earth juice products.
 
Does the label say anything about nutrients?
 
Most potting soils (I am not familiar with Hyponex) will list any included fertilizers.
 
Topsmoke said:
there are a lot of variables that need to be considered to answer that question accurately.  Most of them are dependent on whats in your "soil".  I grow organically so I add a small amount of granulated fertilizer (I'm an Espoma fanboy) into my soil mix and that's enough to get them through the 2-3 month inside before planting out.  Remember a plant synthesizes 96-98% of its self from light air and water so it doesn't need a ton of help.  Inside your fertilizer needs will be dependent on growth rate so soil consistency, air temp, humidity, species all need to be taken into account.  The easy answer is every other watering give them 1/2 to 2/3 of what the bottle says. If the leaf tips start to yellow its too much and flush the soil every few weeks to wash away salt build-up. Compost tea doesn't supply nutrients it supplies microbes which make existing nutrients bio-available to the plants which if growing outdoors can be enough provided you have rich soil.  For liquid fertilizer I really like earth juice products.
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Which Espoma fert do you use?
 
Compost tea alone isn't going to cut it. Not unless you know exactly what the composition of your compost is, and you are prepared to use it at every watering. That's a big commitment. (brewing constantly)
 
Thanks for the advice. I went to the local hydro store and picked up some earth juice grow and earth juice bloom. The guys at the shop had alot of positive things to say about it too.
 
Edmick said:
Thanks for the advice. I went to the local hydro store and picked up some earth juice grow and earth juice bloom. The guys at the shop had alot of positive things to say about it too.
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You can take back the bloom.  It's a waste of money.
 
If you like a liquid based nutrient, it's hard to get more bang for the buck than Alaska Fish, and Alaska Seaweed. (available at Lowe's, Home Depot, and some Wal-Mart)  Use them together, or alternate at each feeding.
 
I know that you are relatively new, but hydro stores are one of the worst places for grow advice.  They are in business to sell you products at premium prices, regardless of effectiveness.
 
I agree with the premium price part cuz this stuff isnt cheap. I'm willing to try new things though. These hydro stores are packed with products promising bigger plants and bigger yields so its a little overwhelming trying to find the right product. Not to mention, that the staff is usually high out of their mind so its like trying to have an intelligent conversation with a toddler.
 
Solid7 i cant say i totally disagree with your thinking on the earth juice bloom (as i have never used it) but i think that a secondary product during the blooming process is beneficial. Ive been growing for a little over 10 years and ive found that once plants have started to bloom that lowering the nitrogen and increasing phos and potassium had increased yields exponentially. And thats just through experience. Im sure many people have had differing experiences though. Thoughts?
 
Edmick said:
Solid7 i cant say i totally disagree with your thinking on the earth juice bloom (as i have never used it) but i think that a secondary product during the blooming process is beneficial. Ive been growing for a little over 10 years and ive found that once plants have started to bloom that lowering the nitrogen and increasing phos and potassium had increased yields exponentially. And thats just through experience. Im sure many people have had differing experiences though. Thoughts?
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graf1.gif

 
Source: Haifa group
60 days from seedling was first harvest
 
This is nutrient uptake - so the amount of each nutrient that disappears from the growing medium
Now I don't know what the plant actually needs / requires but replacing what disappears is what matters, irrespective of how it happens
 
Powelly said:
 
graf1.gif

 
Source: Haifa group
60 days from seedling was first harvest
 
This is nutrient uptake - so the amount of each nutrient that disappears from the growing medium
Now I don't know what the plant actually needs / requires but replacing what disappears is what matters, irrespective of how it happens
Click to expand...
 
Not fair.  What is the growing medium? (container or ground)  What are the ambient conditions?  What type of fertilizer?  How is the dosing occurring? (1 part, 2 part, etc)  Is this in a green house, or are the plants subject to flushing by heavy rain?  Where there any sort of anomalies? (like pests)
 
How can we base our fertilizer on a simple graph?  Did you know that some grow media will actually bind certain nutrients?  (such is the case with coco coir)
 
And how do we know what is in need of replacing besides the obvious? I know all the tell tell signs but in my opinion, by the time a plant starts to exhibit signs of deficiency a certain amount of damage has already been done no? There has to be a way to give a plant everything it needs (within a margin of error) before having to wait for signs of a deficiency right?
 
Edmick said:
Solid7 i cant say i totally disagree with your thinking on the earth juice bloom (as i have never used it) but i think that a secondary product during the blooming process is beneficial. Ive been growing for a little over 10 years and ive found that once plants have started to bloom that lowering the nitrogen and increasing phos and potassium had increased yields exponentially. And thats just through experience. Im sure many people have had differing experiences though. Thoughts?
Click to expand...
 
 
What you've stated is false.  You are not increasing the uptake of other nutrients, (P and K) so much as you are limiting the presence of nitrogen, in your given example.  the plant doesn't take up the nutrients at any different rate, whether we believe it does, or not.  It simply adjusts its uptake of available nutrients. (there is a phenomenon called "environmental dormancy" because of which, many attribute a sudden upturn in plant vigor, to the addition of extra nutrients - when in fact, they've just restored the balance of normal uptake)
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The bottom line is, a plant doesn't take up more nutrients, just because they happen to be there.  You can add as much of any nutrient as you like - but the plant has the same basic requirements. If it doesn't need it, it won't use it, period.
 
Edmick said:
And how do we know what is in need of replacing besides the obvious? I know all the tell tell signs but in my opinion, by the time a plant starts to exhibit signs of deficiency a certain amount of damage has already been done no? There has to be a way to give a plant everything it needs (within a margin of error) before having to wait for signs of a deficiency right?
Click to expand...
 
The science has already been done for us.  Yes, you can overdose nutrients, and still get a good yield.  You can underdose, and get a good yield.  But I'm only trying to save you the frustration of multi-part, super strain, snake oil salesmen.
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Many of us here use 3-1-2 ratio fertilizer, all year, with no cycling of special formulas for different moon phases.  If you are a commercial grower, get nerdy.  Go nuts with it.  Otherwise, keep it simple, plant an extra plant or two (to make up the yield difference of ninja level growers), and knock yourself out.
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Try not to get too jealous of other people's plants, also.  Some people have environmental advantages.  I have to work exponentially harder to grow even a decent crop where I'm at, than some people do, just by throwing their plants in the ground, and fully neglecting them.
 
With all due respect solid7 i kind of disagree. A plant WILL take up more nutrient if its there. How else would you explain nutrient burn? A plant will take everything its given. Good or bad.
 
You answered my last post before i posted it. Apologies for the delayed reply. Thank you for your input.
 
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