Are you fertilizing it?

Citrus are "heavy feeders" and need fertilizing 3 or 4 times a year.

Citrus need to be watered deeply but infrequently. A good deep soaking (to three feet) once every three weeks this time of year is adequate for citrus. As the weather warms the frequency should increase so by summer you are watering once a week - 10 days. Be sure you aren't watering right next to the trunk, but rather at the drip line (edge of branches).

Too much water can push oxygen out of the soil making it difficult for the tree to absorb nutrients from the soil. This causes 'chlorosis' or green veins on the leaves with lighter green to yellow tissue in between the veins.

If the chlorosis is on the new leaves it indicates a lack of iron. If its on the older leaves it means the tree isn't getting enough nitrogen.

This time of year when soils are cool, citrus often look like yours. They won't be actively pulling nutrients from the soil until later next month. In the meantime you can apply a citrus fertilizer at the drip line and water it in when you normally irrigate. Good times to fertilize are Valentines Day, Memorial Day and Labor Day. Follow the instructions on the citrus fertilizer chart at the web site below.

The University of Arizona has several publications on citrus that may help.

Here is a link that might be useful: U of A information on citrus (and more)

I do fertilize the tree... probably only 2x per year. I do the same routine with my orange tree... I'll up them both to 3x per year.

I do use granular citrus fertilizer... but curious, if I'm supposed to spread the fertilizer out under the canopy, and I use drip irrigation, how does the fertilizer dissolve and leech into the soil?

Should I perhaps use sprayers instead that will soak the granules and allow the fertilizer to leech down to the roots?

Should I dissolve the granular fertilizer in a 5 gallon bucket and then pour it under the canopy area so it soaks into the soil, to get the fertilizer down in the roots before it starts to try and flower?

I did a PH test on the soil, and it's coming in at about a 7.0. Should I lower the PH down to about a 6? I read somewhere where higher PH binds the soil and the tree can't uptake nitrogen and iron very well.

What's the best way to lower PH (quickly) in soil?

Thanks.

One thing you might start with is humic acid. Also, fertilizing with good organic ferts, and cultivating compost around the tree might also help down the road. Good Luck :)

I'm with aztreelvr on this one. I would guess too much water. 24 hour soak is awfully long, the roots will suffocate for lack of oxygen in the soil. Especially if you have plastic under that rock. That keeps the soil wet all the way up to the top. go a much longer span between watering. you may also consider removing some rock and cutting back the plastic to a foot past the drip line to give the roots some air.

Not too much watering... that watering for 24 hours was an attempt to get the salt to leach down beyond the roots (if it was a salt problem).

Tree still looks about the same... it's starting to bud and new leaves still come in, but start to turn yellow almost immediately.

I've been feeding it ironite plus for 3 weeks almost, and really can't see any difference.

Nitrogen?

AIR? Is there black plastic under that gravel?

It sounds more and more like prometon damage. Did you, or a neighbor, or the previous homeowner use a really strong "weed killer" anywhere within 30 ft. of the trees in the last 3-5 years? Prometon is found in a variety of product--marketed as "weed killers"--which are actually soil sterilants. These products include Ortho Triox, Green Light Compleet, Pramitol, and the stuff someone's cousin brought home in a milk jug from the warehouse he worked at, saying "We use this on the parking lot, and it really works!" It kills most of the things it touches the roots of, lasts for years, and spreads through the soil with heavy rain or heavy watering. Symptoms inlude severe chlorosis, with brown edges spreading inward between the veins, and yellowing, stunting, and "brooming" of new growth. Citrus are among the most easily affected by low concentrations, along with hibiscus and some of the more tropical palms--such as queen palm or pygmy date. Other plants may be affected, but more slowly, and less severely. Bermudagrass may not be affected at all.

If this is the problem, treatment involves applying humates, either in solid form, or as liquid humic acid. They should be spread over the entire root area: from the trunk out to 3-6 ft out from the dripline. That may involve getting permission from your neighbor to apply it on the other side of that wall, too. Follow the application with watering to 3 ft. deep in the soil over the entire area. New growth should gradually return to normal over the next 2-6 weeks. New applications may need to be made twice a year, until the source of contamination is exhausted. Meanwhile, follow a normal fertilizer regimen.

Hope this helps!
Kevin : )

I'll check with my neighbor. I really don't use weed killers, as I'm not a fan of anything that kills anything.

I did buy some sulphur and plan on adding it to the soil to see if I can get the PH down to 6.5 (it's sitting at 7 now) and see if that helps.

I just seems to be a guessing game, but It'll get resolved sooner or later. Thanks for the tips.

Too much water
Too little water
Needs nitrogen
Needs manganese
Need Iron
PH too high and soil won't release iron

If your soil tests at ph 7 you are fine, the ph is not a big problem.
Could you describe a little more detail about your watering to us? use a 1 gallon milk jug and measure how much water your system puts out and give us an idea of how much, for how long, and how often?
Another problem comes to mind, sometimes after you plant a tree it developed an air pocket. You can check for this and fix it at the same time by poking your garden hose in the ground while it is running and "drilling" holes along side what was the original root ball and then wiggle the hose around some till it fills the hole back. Once the water drains in, pack the soil some with your heal to be sure there is a good soil pack around the original root ball.
I pot or plant in ground a lot of plants every year and I still find maybe 1 or 2 percent that mysteriously have this problem even though I did everything the same as all the others.

My winter watering schedule is twice a week, with 2 emitters, running for 15 minutes. I measured the emitters, and they're dropping approximately 1.5 gals per emitter per 15 min.

Now, what I think really started this was over a year ago, I had my garden on the same line, and in the summer I was running this daily, for 15 minutes a day.

15 minutes isn't nearly enough even if you were applying 15 gallons per minute. The water needs to soak DOWN.

Tree watering by the Valley of the Sun numbers:

One emitter per foot of crown diameter, spaced evenly out on the drip line.
7-10 gallons per emitter, all in one shot--an hour and a half for yours.
Once a week in summer. Once every two weeks spring and fall. Once every three weeks December 1st to January 31st.

Kevin : )

Pokergard,

Here's how much you are watering based on the schedule you provided. 2 emitters @ 1.5 gallons = 3 gallons per hour. Because you are watering for 15 minutes you are providing roughly 3/4 of a gallon of water each time you irrigate.

It takes one gallon of water to moisten 1 cubic foot of soil. A tree the size of yours would have a root volume of roughly 36 cubic feet. It would take about 36 gallons to moisten that much soil.

You need to change your watering schedule to apply 36 gallons of water once every 3 - 4 weeks in winter increasing to once every week to 10 days in summer.

Your lawn should only need water once every week to 10 days in winter. If you don't overseed it only needs water once a month in winter. Because of the rain we've had you should have turned your sprinklers off back in January.

Don't use Ironite on your citrus or other shrubs. It doesn't have enough iron in it for anything except turf. Instead use a 'chelated' iron product or one that is water soluble. The iron has to be in this form for plants to use it.

Here's a link to common nutrient deficiencies in citrus. Your leaf looks like manganese deficiency.

Hope this helps.

aztreelvr
certified arborist

Here is a link that might be useful: Nutrient deficiency in citrus

The emitters put out 1.5 gals each in 15 minutes... so that's 3 gallons in 15 minutes total.... twice a week in the winter... so it's getting 6 gallons every week. I did this by measuring the output of the emitters by using a gallon milk jug.

I do agree with you on magnesium deficiency. Odd that what started this was "probably a salt problem" and here I am adding epson "salts" for magnesium.

The new leaves on the tree are currently a deep green, so the iron has helped, probably along with the TLC I've been giving it weekly.

Hoping epson salts takes care of the rest. Thanks to all on this forum for you advice.

I'll post a post picture in a couple of weeks.