Soil Acidifier - Which plants benefit the Most from it?

[エドガー]

I am in SoCal, OC, where the water is alkaline and hard. I bought a bag of Soil Acidifier today (30% sulfur and 70% gypsum); primarily bought it for my J maples and Kurume azaleas to make them happy in SoCal.

But, I was wondering which of my plants would benefit “the Most” from this Soil Acidifier (trying to be stingy with this small 5lb bag… I don’t want to waste it, if the plants are totally fine without it).

My bonsai and pre-bonsai:
J black pine, san jose juniper, sea green juniper, ume, nanking cherry, jasmine

Garden plants:
Loquat/biwa, grape vine, eugenia, fuyu persimmon, lavender star, guava, meyers lemon, nandina, portulacaria afra, jade plant, snake plant, bromeliad, and all sorts of succulents


Any help appreciated

 

[Lazylightningny]

Ericaceous plants such as azalea and blueberry like a slightly more acidic medium.

 

[エドガー]

Today, I just added the Soil Acidifier to All of my J maples, azaleas, J black pines and junipers. I think that should be good enough - they're my favorite and most valuable plants anyways

 

[penumbra]

Have you tested your soil how it the how or not effect that the water might actually being having on it?

 

[エドガー]

I've never tested the soil... but I've tested the water before (for my own consumption and health). The water is around 7-8ph.

 

[Leo in N E Illinois]

Soil acidifier should be relatively cheap. 5 pounds should have been less than $10 usd. For the farm 100 pound bags of sulfur are less than $75 each. Though you do have to buy more than one at a time. (minimum wholesale)

Calcium sulfate - gypsum - is even cheaper than sulfur. Explore alternate sources if you think they are expensive.

Juniper and JBP do not need particularly acidic soils. I would keep my dose here at the lower end of the range they give you.

from off the top of my head:

Only Japanese maple, ume, nanking cherry, & jasmine would benefit from mildly acidic soil. And of the garden plants
only Eugenia, persimmon, lavender star flower, guava, lemon, and bromeliad would prefer mildly acidic soil. All of these would be fine with a acidity appropriate for Satsuki azalea. Most of these will tolerate more alkaline conditions than the azalea would. For most of North America - I would say most people would not need to adjust the pH of their soils for these trees.

all the rest would tolerate mildly acidic to mildly alkaline soils.

I know nothing about the needs of Loquat (Biwa).

Do you have a unique problem that requires you to worry about alkalinity? Unusually high total Alkalinity water? Unusual soils in the area where dust blowing onto trees is aggressively alkaline? (like downwind of a cement storage silo). What are you using as your potting media? Anything unusual in the mix?

A lot of total alkalinity issues, can be taken care of by designing your potting mix to go with your irrigation water. Remember the real issue is total alkalinity, the amount of Calcium available in the water and the soil, not the actual pH. Focusing on pH is a ''red herring'', you should focus on the total calcium content of your water, and the CEC of your media components.

If you have high calcium content water, setting up a rain water collection system can go a long way to solving the problem, as rain water is low calcium. Adding a larger portion of fir bark or pine bark to your mix will help due to higher CEC of the bark as it decomposes in the mix.

Blueberries are fairly extreme calcifuges, meaning they really hate excess calcium in the soil or water. They need pH far lower, more acidic than Satsuki azalea. For them the standard potting mix is 2 parts bark, one part Canadian peat moss (including the fines), and less than 10 % of the total volume of media add hardwood sawdust. The sawdust is to feed the mycorrhiza the blueberries depend on. This blend when watered with low to moderate calcium content water (total alkalinity less than 225 mg/liter as calcium carbonate) will create a potting media that is between pH 5.0 to 6.0, You can add a fair amount of an inert component like perlite to keep it from compacting.

But in general, do you really need to be worrying about soil pH? do other bonsai growers in your area have a problem? To fruit tree growers in your area have a problem?

 

[エドガー]

Yes, my 5lb bag was about $10 at HomeDepot.
Btw, does it need to be sealed for storage?
My bag has a built-in ziplock slider… but the darn thing doesn’t work and stays Open when slid both ways, lol.

Thanks for the detailed reply!

No, no unique problem that requires me to worry about alkalinity. Just trying to be precautious, mainly for the J maples and azaleas, which I’ve heard have a hard time living in SoCal. Just trying to get the J maples and azaleas as happy and healthy as they can. I keep thinking they are so fragile (especially compared to conifers).

I actually had 6 little azaleas die over the year (3 survived). They were only tiny starter plants bought from eBay last year in early summer 2018. Now, from that experience, I think all azaleas are super fragile in SoCal. But, I think they died because they were in full-sun on the west side of house.

A Japanese-native bonsai nurseryman came over my house once (to deliver two JBPs) and he told me that he bought lots of azaleas a long time ago, and they all died. He said they do not like SoCal weather (but they like NorCal).

I haven’t had any J maples die on me yet. Keeping my fingers crossed. Keeping them in the shade next to a north facing wall and also the shade from the neighbors' 2 story house, only morning sun before noon-time.

I usually use cactus-soil (for its’ high pumice content and good drainage) mixed with potting-soil, for all my plants (EB Stone brand). I do 1:1 for most of my plants.. but for my JBPs and junipers I try to do 2:1, cactus: potting-soil …but sometimes I also do 1:1 too for the JBP and junipers, depending if I am low on a certain soil. Sometimes, I get azalea-soil for the J maples and azaleas (also mixed with cactus soil, for pumice/drainage).
Sometimes I use Kellogg brand cactus-soil (also mixed with potting soil) if I cannot buy EB Stone.

I use big nursery pots (no bonsai pots) for all my plants. Most of my plants are only in development and very young…except 2 old garden JBPs and 1 old san jose juniper, those all have about a 2.75-3.25” trunk, so I think they are 15+yo.

Basically… I just bought the Soil Acidifier as a precaution for the J maples and azaleas, which I hear is difficult for them to live in SoCal.

 

[hemmy]

A lot of total alkalinity issues, can be taken care of by designing your potting mix to go with your irrigation water. Remember the real issue is total alkalinity, the amount of Calcium available in the water and the soil, not the actual pH. Focusing on pH is a ''red herring'', you should focus on the total calcium content of your water, and the CEC of your media components.

I just wanted to highlight this again for emphasis. Quality info!

A Japanese-native bonsai nurseryman came over my house once (to deliver two JBPs) and he told me that he bought lots of azaleas a long time ago, and they all died. He said they do not like SoCal weather (but they like NorCal).

I guess someone forgot to mention this to Nuccio’s near Pasadena. One of the premier azalea growers in the country. There are a lot of different microclimates in SoCal, even with your own yard. Bad positioning, poor water, poor designed substrate for the water, can all make for challenging conditions.

If you are new to the area, you should hit up your neighbor (@bonsainut) for some tips on substrate and water quality!

 

[エドガー]

I guess someone forgot to mention this to Nuccio’s near Pasadena. One of the premier azalea growers in the country. There are a lot of different microclimates in SoCal, even with your own yard. Bad positioning, poor water, poor designed substrate for the water, can all make for challenging conditions.

If you are new to the area, you should hit up your neighbor (@bonsainut) for some tips on substrate and water quality!

Just looked them up on Yelp... wow, looks like an awesome place! I def must visit there someday whenever I want more azaleas.

Yes... I am a n00b, so before I knew any better, I placed them in waaay too sunny of an area last year, full sun and west facing wall, smh lol. Those crazy heatwaves last year too.

Ah, yes... BonsaiNut is actually the reason I bought Soil Acidifier. He said J maples and azaleas could benefit greatly from it, if you are in SoCal with its' alkaline and hard water.

 

[Bonsai Nut]

The plants that enjoy more acidic soils: azalea, gardenia, camellia. Conifers. Maples. Oaks.

Consider this product:

 

[エドガー]

The plants that enjoy more acidic soils: azalea, gardenia, camellia. Conifers. Maples. Oaks.

Consider this product:

View attachment 247632

Looks super awesome! Now I just have to find it in OC.

I’ve just been using MiracleGro Shake’NFeed, since I didn’t know what else to get (besides Osmocote). But your suggestion looks much better than both MiracleGro and Osmocote! Balanced NPK is hard to find too.

 

[Bonsai Nut]

Looks super awesome! Now I just have to find it in OC.

I’ve just been using MiracleGro Shake’NFeed, since I didn’t know what else to get (besides Osmocote). But your suggestion looks much better than both MiracleGro and Osmocote! Balanced NPK is hard to find too.

Ewing has it (numerous locations). So does OC Farm Supply.

 

[エドガー]

Off topic... but, what’s your fave rooting compound?
I just have 0.10% powder from HomeDepot. But always hear about DipNGrow and Hormex.

 

[JudyB]

You could also consider using Kanuma as a soil for Azalea.

 

[エドガー]

My plants are in countless large nursery pots... most of them are 15gal, 7gal and 3gal. So I can't afford using special bonsai soils (akadama, kanuma, etc.). That's why I use cactus-soil, because it contains a lot of hard-to-find pumice and is inexpensive (I know pumice is also available at bonsai stores tho).

 

[Emanon]

You could also consider using Kanuma as a soil for Azalea.

On a related note, I'm trying yamagoke (yamagoki?) moss as a top dressing for those of my trees that prefer both a more acidic and wet soil. It's not that cost prohibitive. I think it will take me years to go through a big block of the dried stuff.

 

[penumbra]

My plants are in countless large nursery pots... most of them are 15gal, 7gal and 3gal. So I can't afford using special bonsai soils (akadama, kanuma, etc.). That's why I use cactus-soil, because it contains a lot of hard-to-find pumice and is inexpensive (I know pumice is also available at bonsai stores tho).

You really should check the ph of your cactus soil. I find cactus soil mixes to be very expensive. From that standpoint there are better choices.

 

[Bonsai Nut]

Off topic... but, what’s your fave rooting compound?
I just have 0.10% powder from HomeDepot. But always hear about DipNGrow and Hormex.

A complicated question that almost deserves its own thread.

Hormex is 100% IBA based - at different strengths (normally 1-3% IBA)
DipNGrow is 1% IBA and .5% NAA (fixed strength).

Hormex is a powder. DipNGrow is a liquid.

You should always match the strength of your rooting compound to the task at hand and the species you are working with. I recommend you refer to the Reference Manual of Woody Plant Propagation (or other literature) to make sure you are using the correct strength. All things considered, for many of my cuttings, I prefer DipNGrow due to ease of use. For hard to root species - and for tasks like air-layers of conifers - I use higher strength Hormex.

 

[エドガー]

Here's a good list of plants and correct strength: https://hormex.com/pages/hormex-rooting-powder-strength-plant-list

Seems like #8 (0.8%) is the most versatile - azalea, juniper, prunus, acer, etc.

 

[MichaelS]

I bought a bag of Soil Acidifier today (30% sulfur and 70% gypsum);

WHOOAH there partner!

Is that pure elemental sulphur + gypsum? While it takes a while, the smallest amount of S will quickly damage plants under certain circumstances.
It works like this... After you have added sulphur (S) to the mix, bacteria slowly convert it to sulphuric acid. With watering, the acid will begin to dissolve calcium carbonate (usually) but the pH will not change until it is all dissolved and has no neutralizing ability left. After that the pH will fall rapidly. This is why it is ESSENTIAL that you first know the pH of the mix you are trying to acidify, AND then know EXACTLY how much to add to do the job and no more. (Gypsum does not alter the pH usually but it's often contaminated with Calcium carbonate in which case it will raise pH)
In container growing, it is BY FAR better to start with the correct pH than to alter it later with S. Everyone should buy themselves a pH kit (like this below) and learn the pH of the materials they use. Knowledge is power.

https://stratagreen.com.au/shop/images/products/mto8000_405.jpg