Citrus: nutrient schedule?

[bradflorida]

I have an orange and grapefruit tree.

I am considering the following schedule:

Fertilize NPK slow release: March, June, September.
Foliar spray of minor elements: April, July October.
Iron drench: April, mid June, September.

Is this routine appropriate?

Thanks

Brad

[phantomcrab]

I contacted Dr. Robert Rouse (UF) about this with emphasis on rejuvenating trees from citrus greening. His reply:

Richard, the most important and essential ingredients in the mix are the macro and micronutrients.  They should be sprayed on the foliage 3 to 4 times per year.  The timing would be when the tree is producing new flush shoots.  New flush comes in the spring when new growth begins, again when the summer rains begin and in the fall about late August to early September.  The summer rains keep the tree flushing with new growth all summer making it an opportunity to make 2 applications about 4 to 6 weeks apart.  The regular ground applications of fertilizer should be continued.  There is not currently a website where this information is given.

So he indicates that major nutrients should be included in the spray along with the minor elements. If rejuvenation is your goal, it takes 2 years to see results.

[Central Floridave]

I typically only fertilize my citrus mid-february (now), and maybe lightly in the summer if we get a lot of rain. 

I've had great results.  I just use a citrus or palm special fertilizer. 

[puglvr1]

I have very young Citrus...3 years and newly planted. My biggest problem is Citrus Leaf Miners (CLM) and they attacked every single "new growth flush" I've ever had making my young trees totally ravished and stunted...so I'm going to be very proactive this year treating them so the tree can grow and be healthy.

Is the Southern Ag Citrus Nutritional Spray a good one to use for minors? Is there one better out there...I'm planning on following the application of 3-4 times a year as per the recommendation...I really want to get them healthy this year.

Brad, your schedule seems like a good one ...but I'm waiting for pros to comment.

What brand Iron are you going to apply? I was thinking of using Ironite? 

[phantomcrab]

Is the Southern Ag Citrus Nutritional Spray a good one to use for minors?

Yes.
I use Dyna-Gro Foliage Pro since it contains NPK too.

[puglvr1]

Thanks Richard! Since mine are planted inground it would be too expensive to use Dyna gro ( I have some but only use it for some of my container plants...are you applying with DG as a "foliar" spray? If so how much are you using per gallon of water? Thanks!!

[phantomcrab]

Thanks Richard! Since mine are planted inground it would be too expensive to use Dyna gro ( I have some but only use it for some of my container plants...are you applying with DG as a "foliar" spray? If so how much are you using per gallon of water? Thanks!!

I use Foliage Pro 9-3-6 which is 20.2514% nutrients = 202514 ppm. Diluting 1 teaspoon to a gallon of water (1/768) gives a 264 ppm (total nutrient load) solution which I use as a citrus foliar spray once every 4-6 weeks after petal drop. Pineapples like it too. The mixture is too concentrated for mangos though.

[puglvr1]

Thanks Richard, my lemon tree always seems to be suffering from nutrient deficiency...even though I apply fertilizer on a regular basis...I read that its quite common with Meyer lemon especially which is what I have. Sometimes the So. Ag just doesn't seem to help much with the yellowing leaves. The problem is they recommend spraying it Dec, Jan. and Feb. but most of my yellow leaves are year round especially towards summer 

[phantomcrab]

Thanks Richard, my lemon tree always seems to be suffering from nutrient deficiency...even though I apply fertilizer on a regular basis...I read that its quite common with Meyer lemon especially which is what I have. Sometimes the So. Ag just doesn't seem to help much with the yellowing leaves. The problem is they recommend spraying it Dec, Jan. and Feb. but most of my yellow leaves are year round especially towards summer 

Giving the lemon foliar NPK should help with the yellowing leaves. The tree could have citrus greening. The disease typically manifests itself with nutrient deficiency symptoms as the roots die. In Florida, lemons and limes simply tolerate it better than other citrus. In April there will be a speaker at the Tropical Fruit Society of Sarasota talking about new citrus varieties. He knows a lot about greening too.

[bradflorida]

Thanks all for the input.

Pugluvr - you sure are persistent, whether it comes to battling bugs, or battling winter damage.

Richard - thanks for the info.  I will probably see you one day at the fruit club meeting in Sarasota.


I read up on iron applications to the soil, and found that chelated iron is preferable to nonchelated iron, as it is much better absorbed or utilized.  It turns out that Milorganite contains chelated iron. 

Brad

[puglvr1]

"Pugluvr - you sure are persistent, whether it comes to battling bugs, or battling winter damage." Ha, ha...IBrad, have NO choice if I want to grow these fruits 

Richard, as far as I know I do not think I have Citrus greening (ACP)...the tree seems quite healthy (just needs extra nitrogen) to darken the leaves... the yellowing leaves looks like the traditional deficiency you see around here...
This was taken last April...

[ofdsurfer]

"Pugluvr - you sure are persistent, whether it comes to battling bugs, or battling winter damage." Ha, ha...IBrad, have NO choice if I want to grow these fruits 

Richard, as far as I know I do not think I have Citrus greening (ACP)...the tree seems quite healthy (just needs extra nitrogen) to darken the leaves... the yellowing leaves looks like the traditional deficiency you see around here...
This was taken last April...

Pug this website has a lot of good info about diagnosing citrus problems including greening.

http://www.crec.ifas.ufl.edu/extension/greening/symptoms.shtml

[puglvr1]

Thanks oldsurfer, will check it out!

BTW, what are some of the great brands of Citrus Fertilizers out there you guys are using with good results. Just used the last of Vigoro Citrus fertilizer from HD and can't get 8-3-9 locally. Wanted to know what you guys recommend, Thanks!

[puglvr1]

So...what are you guys using to fertilize your Citrus, I need to fertilize my Citrus this week and would really
love to hear what some of the better brands out there, Thank you!!

[Mark in Texas]

Wanted to know what you guys recommend, Thanks!

Depends on what a soil analysis reveals.

[sunworshiper]

Your tree looks pretty great puglvr.

I've had good luck with Southern Ag spray. Have tried Keyplex too, but my trees tend to show zinc deficiency and Southern Ag has more zinc than keyplex, so it works better for me. As for granular fertilizer, I use Lukas 4in1 - my local nursery's custom formulation. So that's only helpful to those in the Orlando area.  Citrus do seem to look a bit rattier than other trees to me. So much disease pressure. But they also seem to naturally shed. My Meyer lemon tends to do a big leaf drop around the end of Jan, then burst into bloom and new growth around Feb. It stops growing in fall, and the leaves look progressively more tattered as winter progresses. But it is super productive - had easily 100 fruit this year. I just gave it its spring pruning this past weekend. Here it is post pruning


Here are some images of what the leaves look like as they gradually yellow and drop off.



Oh, and my general fertilizer schedule is:
Granular Fertilizer: Feb, April, June, August
SouthernAg: March, May, July, September
Chelated Iron Soil Drench: August

The granualar fertilizer stimulates a growth flush, then I try to time the nutritional spray for when the new growth flush is 3/4 expanded, which works out to be roughly a month later.

[bradflorida]

Sunworshipper -

I like the idea of applying foliar minors a month after applying granular NPK.  Makes sense. 

Thanks.

[puglvr1]

Sun, Thanks for your help and posting your fertilizing schedule...Very helpful. BTW, your tree looks very nice! Nice shape 

Yup, I have the same issues with my leaves that you pictured! Do you treat your CLM's (new growths only) or do you just let it be since its producing very well for you? Once the tree reaches 4 years old I won't need to treat for CLM, but I have to get it past that point 

This poor Meyer has indured SO much problems in its short life...2 years in a row it had severe freeze damage and the following year the Deer ate 90% of leaves (all that was left was skinny leafless twigs) and every year since I planted it the CLM's have devoured the new growths...I've yet to get more than 2 Lemons out of it,lol...I hope this year will be different. I'm going to be a lot more pro-active with the nutrients and CLM treatments.

[sunworshiper]

Glad that the info on ferts was useful=)

I treat CLM periodically. When the majority of a new flush is getting attacked I spray with spinosaid. Seems to knock it back enough that I don't need to spray for a while. I just let minor damage go unchecked. All my citrus usually have some. Sorry your tree has had such a hard life - looks like it has recovered amazingly well. You can see the xmas lights still strung on mine for warding off freeze damage...

[Guanabanus]

The dark green spots against the yellow are probably symptomatic of the foliar fertilizer sprays.

[Mark in Texas]

The dark green spots against the yellow are probably symptomatic of the foliar fertilizer sprays.

Agreed.  I have used Southern Ag with absolutely no success.  They're on Flying Dragon though which is notorious for shutting down in the winter and at the top of the rootstock list regarding micros deficiencies.   Give me sour orange any day, it always promotes dark green leaves with a minimum of inputs.

Mark

[Millet]

A great many commercial citrus growers use 6-6-6, 8-8-8 or 10-10-10 because they are readily available, cheap, and can be purchased in bulk.   Citrus trees absorb nutrients from the soil in the ratio of 5-1-3. In other words for every 5 parts nitrogen, the tree's root system will absorb 1 part phosphorous and 3 parts potassium. Obviously, in cases of over dosage or deficiency of one or more elements this ratio must be changed to a more appropriate one. Using a fertilizer with a 5-1-3 ratio such as peters 25-5-15 with minors, is especially good for trees growing in containers. I use this ration on both my container and in ground trees - Millet

[Mike T]

Applying fertilizers immediately after harvest and the subsequent major yearly prune is normal in warm climates that allow it. A second lighter application around the drip line is alright  when fruit are small but chlorides in some citrus mixes are not good. I reckon the second application is best being a more natural blend like blood an bone, manure or dynamic lifter due to soil health benefits. A 20:6:14 brew cumulative with all applications is great. A thick mulch layer away from the trunk is also great and improves uptake. Soil health is different from the nutrient status of soils and just as important.

You need to check your soil type and even plant foliage to see what micros to use and think if they are also in your NPK blend. Less is more with fertilizers.

[Mark in Texas]

Using a fertilizer with a 5-1-3 ratio such as peters 25-5-15 with minors, is especially good for trees growing in containers. I use this ration on both my container and in ground trees - Millet

Found it for $53/25 lb. shipped, but why do you think Jack came up with the 20-10-20 in the Citrus FeED line?

[Millet]

Mark In The Great State Of Texas,  Jack's 20-10-20 though not the very best formula for citrus, is really not all that bad.  Citrus like high nitrogen and potassium, and just little phosphorus. 20-10-20, a 2-1-2 ratio fertilizer, offers both high N & K with too much P.   Jacks 25-5-15 W/TM is a relative new formulation of Jacks (Peters Company).  Jacks main customers are the nursery trade, and not citrus.  As said above, research shows that citrus absorb nutrients from the soil in a 5-1-3 ratio, Meaning for every 5 parts N, the tree will absorb 1 part phosphorous and 3 parts potassium.  Therefore, Jacks 25-5-15 is  a 100 percent  correct balanced fertilizer, especially for container citrus trees. If you would like to read further about citrus's 5-1-3 ratio, you will find it in the citrus text book titled "The Genus Citrus" written by Dugo and Giacomo.  - Millet