Surfactant

[Bkue]

I have a few hundred palms and many more tropicals in central Florida. I’m on a high spot and have battled dry sandy soil. I used commercial surfactants with barely noticeable results in the turf. I hear of many people using baby shampoo for same purpose. Anyone ever tried? I irrigate like a mad man but have noticed some serious hydrophobic conditions developing especially around my 200+ Areca’s on the perimeter. This issue has always been present but has exasperated itself with the last couple months of lack of rain. 

[Fishinsteeg234]

I’m not sure if you’re able, but I have always battled hydrophobic dry soils by adding a layer of wood chips as mulch. Most tree trimming companies will give away or even deliver the mulch for free. A 2-4” thick layer will hold moisture and overtime will break down creating optimal growing conditions even during a drought. 

[sonoranfans]

I have had similar issues, the quick answer is that a combination of humic acid as a chelator of hardness(chelator)and SDS(sodium dodecyl sulfate is also called sodium lauryl sulfate ). SDS/SLS is the most potent surfactant available and is used in many detergents and soaps at low levels.  

I would apply both followed by turface mvp(sintered clay which retains moisture) and then surface mulch 3" on top.  If you have hard water, it pays to retain water in the soil, not just water more as this just exacerbates the hydrophobicity problem.   Turface is a permanent moisture retainer and mulching every year or two works organics into the soil column. 

concentrated SDS(SLS):  https://www.bulkapothecary.com/raw-ingredients/other-ingredients-and-chemicals/sodium-lauryl-sulfate-sls/?sku=B520-043-004&gclid=Cj0KCQjw_r6hBhDdARIsAMIDhV8IP3xcw_PWk2Ld8GZ-1YZret9o-yxqWNisWJshDftx_f-TX8VI_bYaAkFQEALw_wcB

My best source of humic acid I have found also has kelp and the liquid form enables the stability of fulvates which are also very important.  

https://www.natureslawn.com/product/natures-magic/

You should only need to apply 2 times(a week apart) to remove the hardness from the sand.  I would take 1 cup natures magic and  a heaping tablespoon of concentrated SDS and dilute to 5 gallons.   This is to correct a problem, annual applications of humic for soil maintenance should he half that(1/2 cup). Then I would use a sprayer to wet all around the root areas, let it sit for an hour and then water slowly with a sprinkler to work it in and rinse away hardness.  The turface should be spread around the root areas to ensure better moisture retention.   The dry season here poses challenges to sandy soil, and just watering more is not the answer long term.  Putting the turface and mulch down will allow palms to grow a more roots and his will also make palms more drought tolerant.  In sandy soils, do not use drippers, they are not appropriate for the transport of nutrients and moisture in sandy soil.  The more your soil retains moisture the less hardness is accumulated on the sand as it means less watering which leaves that hardness in the sand.   After you clean up the hardness in your sandy soil and add the turface and mulch, you will be able to control hardness with only 1 application of humic per year.