Hello. I have a variety of citrus trees in containers that I am trying to bring back into a healthy state. These were inside for the winter and they didn't do as well this year as they have previous years. I fought a massive scale infestation from mid-winter until they could come out and also had issues with spider mites. Most of the insects are now under control but I see what looks like nutrient deficiencies of various kinds on all of the trees. All of these are in very fast draining media and I check them often for root rot. There is no standing water or root root involved. Please advise?

Edit: I fertilize these on a continuous basis (fertigate) with a 3-1-2 ratio fertilizer that contains Ca and Mg in 4:1. I can't get water soluble 5-1-3 locally (nor can I find the Jack's Pro online anywhere). I do have access to speciality chemicals and I'm not afraid to buy them if necessary. Some of these look like they could be Mg deficiency but I'm not an expert on recognizing symptoms. If so I have Mg Nitrate that I can spray if you can tell me which ones need it and in what concentration. Or whatever else they might need. It's also quite warm here at the moment (90s+ for weeks) so if there are temperature restrictions on spraying that I need to know about please do say.

In the past I've used neem oil on these trees but this year I'm skipping the neem and using spinosad, qst-713 (cease), and I hope to give them a summer weight petroleum spray. After reading the UC Davis IPM site on sprays I came up with this one: http://betterplants.basf.us/products/ultra-pure-oil-horticultural-insecticide,-miticide-and-fungicide-.html ("Ultra-Pure") - is this a good spray oil to use? Can I use it in the summer? The label says it's ok for summer use but I've always read to be very careful in the summer. Supposedly this has 99% unsulfonated residue (label: http://www.cdms.net/LDat/ld9IR000.pdf )

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This is from a NOID lemon tree (#1). 10ish' tall. There were 5-6 of these on the same branch as the only fruit this tree is carrying (its first year fruiting - this isn't grafted).


The same tree, wide angle:


The leaves near the single fruit:


New growth on the same tree:

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Citrus aurantifolia (thornless key lime) - leaf discoloration


Wide shot of the new growth on the key lime. It leafed out nicely after dropping quite a few over the winter but there are still a lot of the leaves like above on the older branches.


Same tree. Spider mite stippling? Or is this normal on the key lime? This is new growth - not from winter damage.


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Meyer lemon. 4 years old. Carrying 5-6 fruit from the previous flush and 10ish or so from the current flush + quite a few blossoms. Most of the old leaves on the tree look like this:






New growth on the meyer:


Newish growth on the Meyer (maybe from previous flush or the one before that?)

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Tango Mandarin. 4 years old on flying dragon:


Quite a few like this:




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Bearss Seedless Lime - 4 years old on flying dragon:




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Gold Nugget - 3 years old on flying dragon:
New growth:


Old Growth (sorry about the sunlight - you can see the mottled appearance if you look closely):


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Clementine on flying dragon 4 years old. Still some scale on this plant - working on that. Leaves are uniformly curled inward like below. Quite a few are showing this discoloration as well:




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Midnight Valencia - 4 years old, flying dragon:




New Growth on Valencia:


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NOID Lemon #2 - old. Own root. Carrying 30ish marble sized lemons with another flush w/blooms in progress now. The tree looks uniformly light-green or yellowish green. Much lighter than in previous years:






Spider mite stipling?:


Sorry for the length.

All in all your tree looks to be a healthy tree. The leaf in the fifth picture just looks to be an old leaf and nothing to be of concern. The leaves in pictures 8,9,10 show a deficiency of manganese. The symptoms for manganese deficiency are: Green veins with green borders to the sides of the veins. on otherwise yellowish leaves. Many times this deficiency can be caused by high pH, rather than a shortage of manganese. Everything considered your tree looks to be fairly healthy. The picture of the new growth again shows good coloration. - Millet

These are 9 separate trees. I only took wide angle shots of 2 of them.

Would you say that the Meyer, Tango, and Bearss are all Manganese deficient? I'm pretty sure the pH is high in these pots and the pH of my water is also high but I don't know how I would fix that. Should I make more Manganese available or would it also just get locked out? I can get chelated (edta) Manganese locally if adding it will do anything. Would foliar sprays work for that? Add it as a drench?

You aren't worried about the discoloration on the Clementine? Should I just ignore that? The closest thing I can find to that is boron toxicity but it doesn't really look the same (and I can't see why it should be getting more boron than the others).

Does the midnight valencia look like it could be Mg deficient to you? There are quite a few older leaves with that yellowing from the tip going on. Closest thing I've seen is Mg deficiency but you will know more than I...

And the overall color of the #2 noid lemon tree is ok? It really is much more yellow than it used to be - just because it's carrying fruit or something maybe?

Any opinion on the petroleum oil? I'm trying to finish off the last of the scale without damaging the plants...

Thanks!

Meyer, Tango, and Bearss are all Manganese deficient? = yes

Clementine: = Not 100% sure but it looks like citrus rust mites.

Midnight Valencia = No not Mg deficient, i Manganese deficient

Lemon #2, looks OK if you concerned that it is a little yellow you can give it a little nitrogen

I suspect that the medium that the tree's roots are growing in has over time risen to a high pH level, causing manganese to become non soluble. This problem is probably from your irrigation water. Do you know the bicarbonate and carbonate level of the water you are using? There are several methods of lowering the pH. One is to incorporate the proper amount of acid to the irrigation water, and the other is use a acid based fertilizer. On fertilizer bags, it will state the potential acidity as Calcium carbonate equivalent per ton. Example, on the fertilizer 25-5-15 (5-1-3 ratio), the potential acidity is listed as "608 lbs. Calcium carbonate equivalent per ton". Meaning the acidity potential of the fertilizer can neutralize 608-lbs. of calcium carbonate per ton. If your water is bad, you can also switch to using rain water, or a rain water blend. Spider mites, aphids, and scale are very easy to control with Horticultural oils. I use Pure Spray Horticultural oil, there is also one called Volk Oil. I believe Home Depot carries Volk Oil.

Millet (232 BO-)

Thanks! I was thinking most of these were Mg so I'm glad I asked. The Mn makes more sense

The pH of the water is 9.8 with a "Total Hardness" of 110 CaCO3 equivalent (also listed as "Total Hardness: 7 grains per gallon").

I see from reading the forum that you like the Jack's Pro 5-1-3 ratio fertilizers. I can't find these locally (used to be able to - before they were sold now my local place doesn't carry them) nor can I find a source online. Do you know one? What is the neutralizing value of that fertilizer? Would you suggest I use it in this situation with my water?

If I try to modulate the water with acid what pH would you suggest I aim for with the water? 6.5? 6?

Thanks again for the replies.

Jack's (J.R.Peters Co) 25-5-15 Professional water soluble fertilizer for continuous liquid feeding programs, is on Jack's professional grade list. Therefore, it is not sold retail, but only through wholesalers or dealers to the nursery and greenhouse trade. It is sold only in 25-lb. bags. I purchase it through one of two wholesale greenhouse suppliers in the Denver area. I normally purchase 50-lbs. at a time.The neutralizing power of the fertilizer was used in the example I listed above.

With the high level of CaCO3 and a pH of almost 10, an acid treatment would do best. Acidifying irrigation water to pH 4.5 (zero alkalinity) in combination with ammonium fertilizer helps drop medium pH over time with less risk than a strong acid drench. Various acid can be used, but sulfuric acid is normally the acid of choice.

A common high acid fertilizer sold at retail and at most locations is 30-10-10.

Millet

Yes I have access to greenhouse suppliers just no one that is selling Jack's/Peter's anymore (sadly). I can't find online sources either.

So if I go the sulfuric route (I already have an injector that is sulfuric compatible) could you maybe explain the pH target of 4.5? I thought the target would be much higher. Would that be for a continuous feed/water basis? All output from my hose to my pot should be putting out 4.5 pH going forward or would that just be until I see deficiencies disappear at which point I move up to something like 6.5 or so?

I guess I'm confused in that 4.5 seems very low to me so I must be missing something.

I've read in some places that un-recycled battery acid can be used for this purpose - would you suggest trying that or should I look for a professional product specifically designed for this purpose?

Thanks again!

http://www.amleo.com/jack%27s-pro-water-soluble-fertilizer-25-5-15-high-performance-25lb-bag/p/J25515/

Without being at your location, I can only assume from the information that you have posted about your water supply has over time caused the trees problems. The water's high alkalinity from Calcium, and also probably high levels of bicarbonates and some level of carbonates has caused this situation. With every watering your water is adding additional alkalinity, and therefore increases the problem. You can lower the water's alkalinity to zero, just by lowering the pH to 4.5. At 4.5 pH water has no alkalinity. Therefore, the combination of lowering your irrigation water to 4.5 pH and an ammonium fertilizer will drop the medium's pH over time. By taking the pH of your container root zone you will know when you have reached a pH of 6.5. Then you can simply stay at that point or very near, by a combination of fertilizes and supplying the correct water pH.

The best book I've read on this type of problem is titled: "Understanding pH Management For Container Grown Crops' by William R. Argo and Paul R. Fisher.

I see it is now on the Internet. You should study it, I'm sure it will give you a clear understanding, and give you the complete information to solve you problem..

http://www.caes.uga.edu/publications/pubDetail.cfm?pk_id=7351

The best to you and your trees.
Millet

Thanks very much! And for the link to the Jack's for some reason I couldn't find that when I searched.

Just as an general info :

Only Poncirus has that troubles with alkalinity.
If you use Citrus aurantium as rootstocks, you will have no problems.

In europe gardeners use just some drops of vinegar in water to neutralize alkalianity in water.

I have a question regarding the use of acidic fertilizers to lower pH of stock irrigation water to be stored in a 30gln pail for about 2 weeks.

I've read so much info on this forum that I may be mistaken, but isn't nitrogen derived from urea bad for citrus trees? My Miracle Grow Acid Fertilizer has 27% urea, so could that be used?

Also, if you are preparing irrigation water at 200PPM with Jack's fertilizer and you lower pH with 30-10-10 acid fertilizer, wouldn't the solution become too strong? Should you add the nitrogen % from both fertilizers to make the 200PPM solution?

Thank you all for clarification on this subject.

Robert

P.S. Millet, thank you for the link! I look forward to reading it.

Sanguinello posted: "Only Poncirus has that troubles with alkalinity".

Sanguinello, I'm not sure where this information comes from, but it is certainly not correct.

Vinegar is used by some hobbyist, but because vinegar is an organic acid, rather than a mineral acid, it life span is exceptionally short.

Millet (231 BO-)

robby_hernz, you would not use both fertilizers. Jack's 25-5-15 is also an acid fertilizer, and will neutralize alkalinity at the rate of 680-lbs. per ton. There are a lot of acidic reaction fertilizers. All ammonium based fertilizers are acidic reaction fertilizers.

A pure grade of urea, that is very low in biuret is commonly used as a source of nitrogen in citrus. Urea that contains biuret DOES cause problems with citrus. Biuret, is a byproduct from the manufacturing of urea. - Millet

I found a source for the sulfuric (35%) and the AlkCalc necessary to figure out what % to use. I confirmed with JR Peter's that I can mix the sulfuric with the 25-5-15 product in a concentrate before injection into my water.

But now I'm wondering what you all do for Ca on the citrus? There's a very little amount of dolomitic lime or calcium sulfate in my media but I was counting on having some from my fertilizer.

What kind of Ca program should I follow if I go the sulfuric + jack's pro 25-5-15? Foliar applications of Ca Nitrate? If so do you have suggestions for how often and at what concentrations?

Also: the link above was interesting and useful as far as it goes but I couldn't find the rest of the series for how to fix problems etc. I did talk to JR Peters and looked around online and found that this is useful: http://extension.unh.edu/Agric/AGGHFL/Alkcalc.cfm