Fuyu Persimmon leaves yellowing

Zone 10. This is a “Jiro Fuyu”. Bought it as a dormant 1 year old pot last winter. We converted a 4x4 section from the raised garden bed to a dedicated pot for the tree. Dug down about 3’ and filled with no-fertilizer-added bagged “top soil”. Last year, it’s first in ground, was fussy. Did well at first, then the leaves got yellow at the edges. I did not prune at all (prob should have). It’s growing great now but just noticed some chlorosis starting! I’ve been watering with the hose 1-2x a week as the water drains quickly I think. Native soil is sandy. Water is alkaline but not sure exact pH. I dug down 5” and soil is fluffy and moist not boggy. I turned off drip line in case it’s too much water. Any ideas and help is appreciated!

Hi Jane,

Your tree is suffering from deficiency, but the question is whats causing it. I don't mean what element is your tree lacking, I mean whats blocking the absorption of that element. There is a chance its just lacking, but your comments about water quality are alarming/complicating from a diagnostic standpoint.

I would test your pH at about 5" down to rule out alkalinity blocking micro and macro nutrient absorption. I would also test your NPK levels. You can typically pick up these types of test kits around 20 bucks online. You'll want the test kits with the capsules, and Leaf Luster products have worked well for me regarding around the house testing.

My only concern is the source of alkalinity in your water, because if it's from high calcium, that can block absorption or transfer of certian nutrient like magnesium. In fact over abundants of several elements can block absorption or assimilation of other essential nutrients leading to deficiency symptoms. So by increasing nutrients based on leaf diagnosis of the deficit element, without proper tests, can sometimes only increas the problem and increase unnecessary salts in the soil biome harming the one source that best feeds the flora.

Anyway once you've ruled out pH being off, and over/under application of N, P and K, it would be safe to supplement with some liquid kelp and epsom salt. Just follow the directions on the liquid kelp bottle for mixing up 2 gallons of kelp mix, then add in a tablespoon of Epsom salt. Make sure your tree is well watered, then add the supplement mix evenly to your soil. If its a mobile macro nutrient like Nitrogen, which could be indicated by unaffected green tips, and deficent older leaves, just fertalize accordingly. A standard application of any ballenced or specific NPK ratio for targeting that deficiency can be foiler feed to work quickly, and organic options are available. A foliar feed is the best bet to curb deficiency, while waiting for any ammendments on the soil to kick in.

If your pH is high, thats the first issue you'll need to address. It won't be a fast solution as it typically takes time to use some supplements that lower pH, as its commonly a bacterial process utilizing sulfer which makes the pH alteration as a byproduct of digestion within the biome. My guess if its high pH, it is a build up of alkaline salts in your soil most likely from high calcium. You'll need to find a better souce of water like rain catchment or a Reverse Osmosis filter to stop that issue from reoccurring. With just good quality rain water for flushing those exess minerals, it will start leaching those salts out, which should start to reverse the process. Deep infrequent waterings when needed are best, verses frequent shallow waterings.

Other options are available to help alter your pH, but you'll need to have quality water, and way to easily test pH, like a pH meter. If you do, you can mix a solution of ACV with your water to a pH of 6.5, and use that to flush salts with deep waterings. It will help flush the salts, and counter the alkalinity, while giving slight pH adjustments when you water helping bringing your pH back to normal. Once you've determined oz per gallon of ACV for the proper water pH, you can use a garden hose fertalizer mixer/applicator to do those deep waterings at proper ratio.

Im sure you have lots of other questions, but that's my best suggestions to should get you started.

Hi Jane, and welcome to permies! You probably already know that chlorosis is most commonly an indicator of iron deficiency. Your soils may have plenty of iron, but if the pH is high (you mentioned alkaline water) then it tend to get bound up in insoluble forms. The best thing you can do is try to lower the pH and see if that gets the iron moving into the tree, and sulfur is an easy way to do this. Mulching heavily probably won't hurt, either, and you can try using something like pine bark or needles if you have access to them to counter alkalinity. See if you can switch to collected rainwater to take care of this tree.

Sometimes it's not iron but manganese that's the issue in chlorosis. Without a soil test it's hard to say what's up, but you could see if other growie types in your area have similar experiences.

Thank you for the thorough and informative answers! I was secretly hoping to avoid going knee deep into the intimidating journey of soil tests and the like, but this is my husband’s dream tree so I’ll forge bravely ahead, and order those tests. Im sure I’ll be back with a million new questions! Thanks for the support!

Edit: I’m moving this question to the fruit tree forum in a new post.

This is bad! I need some quick intervention!! Help me out soil gurus! Ok I’m overly dramatic but see my laboratory tested results and you’ll get it!

How do I fix these problems??? I have not fertilized this area lately. Last year I added a bag of potting soil on top, as the dirt had settled.  A week or so later, I realized it had fertilizer added, so I scraped it all off and replaced with a “plain” bag of “topsoil”. The planter box was originally filled with unfertilized soil, mixed into native sandy soil. What went wrong?

I have 100 gallons of rainwater to help the ridiculously high pH, but it won’t last all summer.