I'm having trouble with some foliage on my Prestige and Amazon 6.5 " plants. At first I thought it was photo tox. from Truban which I just recently applied to the Prestige but did not apply to Amazon yet the foliage is doing the same thing. From a media extract E.C. / P.H. test the prestige has an ec of 4.5-5 (over six plants) and a ph a 5.4. The amazon has an ec of 1.5-3 (over three plants) and a ph of 5.6. I realize the E.C. on the prestige is quite high and I'm hoping that it is a result of the Truban and not the fertilizer program as the plants are fairly wet and it doesn't seem right to leach them until they dry out a little more. As you are aware, Truban should be applied to an evenly moist plant then re-watered with clear water to help it move around with in the soil, resulting in a wet crop for a few days. I constant feed with 20-8-20 at 225ppm and use a flood bench system. Any suggestions or insight would be greatly appreciated. Thank you, Chad Labbe

I have the same issue with some of my Amazone 6.5" plants also.
I haven't used and Truban. I constant feed with 20-10-20.
I also have some Freedom Bright Reds with yellow leaves. Not all the plants.

Chad, At the low soil pH you have in your crop the availability of Calcium and Magnesium is greatly diminished. Did you incorporate dolomitic limestone into the soil mix to adjust the pH and add an initial charge of calcium and magnesium? If soil tests indicate low calcium and magnesium I would use calcium nitrate (15.5-0-0) to add calcium and bring the pH up a bit and also a treatment of magnesium sulfate (epsom salts) to add needed magnesium. ....Michael Pawelek
PS- Do not mix calcium nitrate and magnesium sulfate together in any concentrated tank mix.

Chad L .

We have a few questions for you....

1). Do you have the crop shaded?
2). Do you have EC and pH levels prior to applying the Truban?
3). The pH is on the low side; Do you have a recent water analysis?
4). When the symptoms first appeared did the timing correlate with the Truban application?
5). How is the root health of the plants?

Please get back to us and we'll try to determine the cause for the symptoms. Thanks!

Yes the roof is shaded in the area that these plants are grown, however it is a gutter vented house and some sun does hit the outer edge of the prestige crop but not in the house where the Amazons are located.
I don't have a E.C./P.H. test recent enough to this event to be relevent on the prestige (3 weeks old but much better looking numbers). I did do a test though on the amazon prior to truban (the numbers i posted yesterday) and post truban (today) and the E.C. was at 5.30 as compared to 3.00 yesterday and the PH was down 2 points to 5.3.
The symptoms do kind of correlate in timing with the Truban but I believe that this is just by chance, as the amazon had the symptoms prior to the application.
Our water is fairly alkaline (PH 7.9) so I inject with sulphiric acid to bring the PH down to 6.2, maybe a little low in retrospect.
When the plants are taken out of the containers the root system looks great, very fiborous and a perfect white color, I have no concern about the look and health of the root system. Hopefully this info will give you a little more insight, and I'm looking forward to your recomendations, Thank you , Chad

Chad L -

The symptoms appear to be related to high light levels combined with possibly being allowed to dry out too much under the higher light levels. Sun scorch is typically expressed on the newly expanded foliage and older foliage as the burnt patches you are seeing between the margins. Some of the pictures also show some leaf rolling which is an indication that the plants were allowed to dry out too much. Do you notice a pattern in the greenhouse where the plants are showing the sypmtoms? Perhaps the plants on the edge of the benches are more symptomatic. The high EC levels will also cause some marginal burn when the plants are allowed to dry out. Poinsettias will tolerate the higher EC but the soil must remain moist. The higher EC may be the result of the Truban application which could also be contributing to the leaf scorch and roll. Leaching the plants well should reduce the EC levels.

The foliage on the Amazone is also showing sypmtoms of a nutrient deficiency on the new foliage. This is probably the result of the low pH. We recommend sending in a soil and tissue analysis so we can get a more clear picture of the what is going on in the soil and tissue before we make recommendations to correct the deficiency. Constant liquid feed with the 20-8-20 is pulling your pH down so you should consider alternating your feed program with a 15.5-0-0 or a 15-5-15. A nitrate based nitrogen will not reduce the pH the way an ammonium based nitrogen will.

Hope this helps! Please let us know when your soil and tissue analysis results come back and we can take a look. Thanks!

This message has been edited. Last edited by: Ecke Ranch Tech Help,

Yes there is a pattern allong the sunny side of the bench in which the symptoms are more visable. I'm glad to hear that sun burn is the likley culprit with the plants having been on the dry side with our extreme heat and bright september days this year. Always better than hearing it is a disease or insect problem.
I will alternate now with a cal-mag 14-0-14 (nitrate based N) to help the defficiency in magnesium and raise the PH in the soil.
I will also get a tissue analysis to have a closer look at what is going on with my specific nutrient levels.
Thanks again for the advice!