Author Topic: Opinion wanted about a fertilizer I just bought...  (Read 3817 times)

MarcV

  • Member
  • ***
  • Posts: 34
  • TheCitrusMan
    • Schoten, Belgium
    • View Profile
Opinion wanted about a fertilizer I just bought...
« on: August 09, 2015, 04:51:06 AM »
I just bought a osmocote type fertilizer for my citrus plants and I would like to hear the opinion of others about its composition...
I know the NPK ratio isn't optimal for citrus but finding a fertilizer with the right ratio is next to impossible... ::)

N-P-K : 17-9-11 + 2%MgO

0,01% boron
0,025% copper
0,22% iron
0,03% manganese
0,01% molybdenum
0,008% zinc

According to the instructions one should apply 40 to 50 grams of fertilizer per 10 litres of potting soil (don't know how much that is in non-metric... :-[), one application per season.

A comment I got on another forum is that there's too little magnesium. I have no idea how much magnesium citrus needs...

All input welcome! :)
...but I could be wrong...

Axier

  • Member
  • ***
  • Posts: 56
    • Basque country Z10 (Cantabrian coast)
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #1 on: August 09, 2015, 06:15:27 AM »
Marc, don't get crazy with N-P-K ratio, your fertilizer is good enough for citrus. Osmocote works very well in containers.
If you see any micro deficiency, you can correct it with a foliar application.
I do it and you will surprise how effective and fast it is.
I use Bayfolan-S for foliar feeding and I am very happy with it, it is a very good foliar fertilizer. It has macro nutrients too, is a complete fertilizer.
For plants wich I want a fast and optimal growing, I use a continuous feeding of 200 ppm N of Foliage Pro, but it is a bit expensive for a massive feeding.
« Last Edit: August 09, 2015, 07:00:15 AM by Axier »

MarcV

  • Member
  • ***
  • Posts: 34
  • TheCitrusMan
    • Schoten, Belgium
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #2 on: August 09, 2015, 07:57:22 AM »
Thanks for the reply. I do have a good liquid fertilizer for citrus with about the right NPK ratio but I'm still having issues with deficiencies, probably caused by the pH value of our tap water which is actually way too high (average 7.9 according to the data of the tap water company). This probably causes iron deficiencies. This liquid fertilizer can also be used for foliar application. Maybe I should do that! :) Never tried that before...
...but I could be wrong...

Axier

  • Member
  • ***
  • Posts: 56
    • Basque country Z10 (Cantabrian coast)
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #3 on: August 09, 2015, 10:19:36 AM »
Surely it is as good as Bayfolan, it will help your plants, no doubt.
I recommend you foliar applications, you will be happy with the results.
An important thing, apply it with high humidity, without cold and nor wind.
A quiet afternoon after a sunny day or a cloudy day with no rain and good temps  are good moments.
Apply the fertilizer mostly over the underside of the leaves, where mainly the leaf stomata are.

MarcV

  • Member
  • ***
  • Posts: 34
  • TheCitrusMan
    • Schoten, Belgium
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #4 on: August 09, 2015, 11:33:37 AM »
Thanks for the good advice! :)
...but I could be wrong...

Millet

  • Moderator
  • Hero Member
  • *****
  • Posts: 4798
    • Colorado
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #5 on: August 09, 2015, 11:55:08 AM »
The efficiency of a foliar spray as far as nutrient absorption into the leaf is highly dependent on the contact angle of the liquid solution that is sprayed on the leaf.  The lower the angle of the liquid to the leaf surface, the more thorough is the coating of the leaf's epidermis, and the better translocation of dissolved nutrients into the leaf's cells is observed.  The value of the droplet's angle can be successfully decreased by the application of a good surfactant, such as TW-20 (Tween-20) which reduces the surface tension of the droplets, into a film over the entire surface of the leaf .   An application of a surfactant can increase the efficiency of the foliar spray by as much as 60 percent.  - Millet

MarcV

  • Member
  • ***
  • Posts: 34
  • TheCitrusMan
    • Schoten, Belgium
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #6 on: August 09, 2015, 01:00:39 PM »
Thanks Millet. Apparently small details can make a difference.
Is Tween-20 some kind of soap? Would it be possible to obtain the same effect by adding some soap to the fertilizer solution without damaging the plant?
...but I could be wrong...

Millet

  • Moderator
  • Hero Member
  • *****
  • Posts: 4798
    • Colorado
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #7 on: August 09, 2015, 04:29:31 PM »
Yes, you can use a soap or a detergent.  You might have to add more when using a soap or detergent to obtain a spray that makes a film like coating on the leaf surface, instead of drops . - Millet

Axier

  • Member
  • ***
  • Posts: 56
    • Basque country Z10 (Cantabrian coast)
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #8 on: August 09, 2015, 06:58:01 PM »
Many foliar fertilizers have sufartanct included in the solution, read the label before.

Millet

  • Moderator
  • Hero Member
  • *****
  • Posts: 4798
    • Colorado
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #9 on: August 10, 2015, 05:44:25 PM »
Foliar nutrition cannot replace or eliminate the natural way of nutrient uptake by plant roots.  In general, foliar application of mineral elements is not so effective as to cover the complete nutritional requirements  needed by plants.  It mainly results from restrictions in applying increased doses of mineral nutrients or it insufficient translocation from leaves to roots.  Nevertheless, depending on plant species, a significant portion of plant requirements for mineral nutrients (mainly microelements) can be covered by foliar nutrition. Because of the polar characteristics of the leaf cuticle and pectin layers (negative charge), these layers contribute to a much higher efficient translocation of apolar and cation molecules rather than anions.  For that reason, a low efficiency is observed for foliar nutrition with mineral nutrients in anion forms (NO3, P, S, B, Mo),  and a high translocation (leaf absorption) for cations (NH4, K, Ca, Mg, Fe, Mn, Cu, Zn), - Millet
« Last Edit: August 10, 2015, 06:19:55 PM by Millet »

Axier

  • Member
  • ***
  • Posts: 56
    • Basque country Z10 (Cantabrian coast)
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #10 on: August 11, 2015, 04:59:09 AM »
Interesting! Thanks!
I am agree with you, of course, foliar fertilization can not replace root fertilization, I do it as an aid to it, but, as mentioned in the excellent document you linked in other post (thanks again): "Foliar application of chelated fertilizers is often more effective than soil application"
I have to confess that, at first, I was a little skeptical with foliar fertilization, but I had to pay to results.
I never got a so perfect green leaves with my citrus before, and in few time.
Worth a try!
« Last Edit: August 11, 2015, 05:21:52 AM by Axier »

MarcV

  • Member
  • ***
  • Posts: 34
  • TheCitrusMan
    • Schoten, Belgium
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #11 on: August 11, 2015, 06:41:11 AM »
Thanks again for the info! :)
...but I could be wrong...

Millet

  • Moderator
  • Hero Member
  • *****
  • Posts: 4798
    • Colorado
    • View Profile
Re: Opinion wanted about a fertilizer I just bought...
« Reply #12 on: August 26, 2015, 10:29:07 PM »
Below is a list of fertilizer elements and how well they absorb into a citrus leaf when used as a foliar spray.

Urea -----  Exceptionally good.
P  as  Phosphoric Acid ----- Average
P as Ammonium Phosphate ----- Average
K as   Potassium Carbonate----- Good
K as Potassium Chloride -----  Poor
K as  Potassium Nitrate----- Poor
K as  Potassium Sulfate -----Average
C as Calcium Chloride ----- Very Good
C as Calcium Nitrate ----- Very Good
Mg as Magnesium sulfate  (Magnesium Sulfate) ----- Good
Mg as Magnesium Chloride ----- Very Good
Mg as Magnesium Nitrate ----- Good
Fe as Iron sulfate ----- Very Good  (may burn citrus leaves)
Mn as Manganese Sulfate ----- Very Good
Zn as Zinc Nitrate ----- Good
Mo as Sodium Molybdate ----- Very Good
Chelated Trace Elements - Very Good

Millet


« Last Edit: August 26, 2015, 10:32:50 PM by Millet »