I know this is a difficult question, not knowing all of the variables but how much iron would you dilute and spray over the soil of trees in 3 gallon pots per 100 if they are showing iron deficiency and how long should I wait to decide if it needs to be repeated?

Hershell, Skeet, must have missed your question. here is the rate of application for Iron chelaes. Fe chelates are applied as a soil drench, or as a foliar spray at the same rate of 8 oz./100 gal. ( 2-grams per gallon = ½-¾ tsp. gal.). For application on citrus, soil drench is the recommended application. Hope this helps. - Millet (873-)

Thanks Millet, that was exactly what I needed to know.

what is the recommended amount of lime per 3 gallon pot it the ph is 8.3.

Lime is a caustic, therefore will raise the pH. If your container is now at 8.3 adding lime will make it go higher. You can lower the pH by using acid type fertilizers, or acidifying your irrigation water. - Millet (849-)

Now that I have my PH meter calibrated I have my soil PH in check again , I hope. My water HP is 8.5 ,soil PH was 5.7 and after liming the soil PH is 6.5. I am using a Hanna meter, and the pore through method. How do others check there PH? Just curious.

There are several methods for measuring medium pH. These include the various dilution methods (1:1, 1:2 and 1:5 methods), that refer to different volume ratios of media to water. The saturated media extract (SME) method, in which just enough water is added to bring the media to saturation. The pour thru metod, in which water is poured through the pot to displace the water already contained in the media, and the squeeze method, in which the solution contained in the medium is squeezed out.

1:2 Method
Measure out a known volume of root medium in a beaker or cup [usually 2 to 4 ounces (60 to 120ml)]. The beaker should be firmly filled with the root medium so that it is slightly more compressed than when it was in the pot. Place 2 equal volumes of distilled water into cup. Allow the solution to equillbrate (30 to 60 minutes) before measuring pH. Measure pH directy in the slurry.

Saturated Medium Extract (SME)
About 8 oz. (300 ml) of fresh medium is placed in a cup. Distilled water is SLOWLY added while the sample is constantly stirred with a spatula or knife until it has reached a consistent moisture level. This is determined to be when the sample behaves like a paste, the surface glistens with water but there is no free water on the surface of the sample. The slution is allowed to equilibrate for 60 minutes. Measure pH in the paste. (This is the method I usually use)

Squeeze Method
Irrigate the pot one hour before testing, making sure the medium is thoroughly wet. Allow the pot to drain for 30 to 60 minutes. Squeeze the solution from the media. For a cleaner sample, media can be squeezed through a paper towel or coffee filter. The volume of solution needed will depend on the type of pH meter used for testing. Measure the pH in the extracted solution.

Pour-Thru Method
Hershell evidently already knows how to do this method. But I will explane for the other members.

Irrigate the pot one hour before testing, making sure the medium is thoroughly wet. Allow the pots to drain for 30 to 60 minutes. Once drainage has stopped, place the pot to be sampled into a clean dry plastic saucer and pour onto the surface enough distilled water to get about 2 oz. (50 ml) to come out of the bottom of the pot. The leachate is the sample. Measure pH directly in the leachate.

Note: all of the above methods can also be used to measure the electrical conductivity (EC).

Millet (841-)

evaldas I have that too , but I also got some Epsome Salts from UK and this ine in the 25kg bag looks like the "original" one

Baumgrenze this is what I get on that link

"Sorry, I couldn't find it!

404: Not Found"

I took the wrong url from a search I had open. My apologies. This should work.

http://www.lycheesonline.com/landscape/pdfs/PlantFertilizing.pdf

This paragraph is on page 4, below the image of a 'guaranteed analysis form.'

Phosphorus and potassium contents are expressed as oxide equivalents, a relic persisting from and related to historical methods of analysis. Do not worry about this convention since fertilizer recommendations are expressed in terms of P2O5 and K2O, the same as used on the tag. Other nutrient contents are expressed as percentages of the element.