Last effort to grow a Brahea edulis in my garden

[Phoenikakias]

I have lost up to now 4 or 5 specimens over the decades. I am not sure I have realized any wrong practice in their cultivation. I understand that as any other Brahea is rather root sensitive, but I had never disturbed the root system of any of my previous victims. So I decided to give a last try with this sp and more specifically from the very first stage of a plant's life, namely the germination. I got hold of some edulis seeds from the Marimurtra b.g., which resulted in several seedlings in a community pot. As I do not wish to disturb their roots, I am thinking of planting out the whole group in to the same spot and may the bravest seedling survive! Are there available  any particular advice to this purpose, especially regarding soil consistency and pH? My soil is, as you already know, alkaline (from 7.5 to 7.8) and stony irrigation water even more alkaline (at least 8.2). I begin suspecting that this sp needs a more acidic soil but it is a Brahea, growing in a warm temperate habitat with volcanic soil of various types , even alkali basalt. So if someone is aware of own soil properties, where a plant of this kind thrives, survives, hangs on etc, such information will be deeply appreciated. 

[Harry’s Palms]

I can’t help as I have never tested our soil . We are warm temperate as well and I planted one about 27 years ago , bought as a seedling in a 3” band from a palm collector . At that time I didn’t know how root sensitive these were . I dug a hole and planted it . It grew very nicely and thrives down near the bottom of my hill where it is coldest. It doesn’t see frost at all and coldest temp down there is 36f. I hope you can figure out what is killing your B. Edulis , they are quite the statement in a garden . Harry

[Darold Petty]

Both your soil and water pH are problematic,...... https://en.wikipedia.org/wiki/Guadalupe_Island

Good luck !  

[Phoenikakias]

53 minutes ago, Darold Petty said:

Both your soil and water pH are problematic,...... https://en.wikipedia.org/wiki/Guadalupe_Island

Good luck !  

I can handle it, provided I know that a certain plant is or may get in to trouble because of this.  Brahea armata on the other hand seems loving alkaline soil, in fact mine had been planted in to a hole with limestone gravel as fill in and it exploded with growth from the very beginning. So I could not consider readily alkalinity as a potential problem for other Brahea spp.

[Jim in Los Altos]

They are painfully slow growing while in the seedling and pre-trunking stages even under optimal growing conditions. I planted this one as a small seedling thirty years ago. My soil is neutral and clay based. Irrigation water is very alkaline at about 8.2. It gets watered once per week in the summer. Potassium deficiency has occasionally been a problem but I feed it more often now and the problem has subsided. These are really tough, drought tolerant palms as well as tolerant to freezing temperatures though mine hasn’t experienced that in eighteen years. 
 

[Phoenikakias]

9 hours ago, Jim in Los Altos said:

They are painfully slow growing while in the seedling and pre-trunking stages even under optimal growing conditions. I planted this one as a small seedling thirty years ago. My soil is neutral and clay based. Irrigation water is very alkaline at about 8.2. It gets watered once per week in the summer. Potassium deficiency has occasionally been a problem but I feed it more often now and the problem has subsided. These are really tough, drought tolerant palms as well as tolerant to freezing temperatures though mine hasn’t experienced that in eighteen years. 
 

How do you cope with the little by little alkalization of the soil through irrigation water?

[Jim in Los Altos]

14 hours ago, Phoenikakias said:

How do you cope with the little by little alkalization of the soil through irrigation water?

Nothing special, Konstantinos. Just PalmGain fertilizer three times per year.  

[dalmatiansoap]

Any ideas how to improve anchoring? I don't know if it's problem with it's roots or might be something else? It's going good but still isn't well anchored after 7-8 years in the ground 

[Phoenikakias]

10 hours ago, Jim in Los Altos said:

Nothing special, Konstantinos. Just PalmGain fertilizer three times per year.  

Does it contain Sulphur?

[Phoenikakias]

1 hour ago, dalmatiansoap said:

Any ideas how to improve anchoring? I don't know if it's problem with it's roots or might be something else? It's going good but still isn't well anchored after 7-8 years in the ground 

This is a matter of serious concern for the future.

[Jim in Los Altos]

9 hours ago, Phoenikakias said:

Does it contain Sulphur?

Yes.

[Jonathan]

It contains Sufur, lol!

[Tomas]

All the NPK fertilizers contain sulfur, the potassium is there in form of potassium sulfate, but the fertilizer is not acidic, I think 

[Phoenikakias]

6 minutes ago, Tomas said:

All the NPK fertilizers contain sulfur, the potassium is there in form of potassium sulfate, but the fertilizer is not acidic, I think 

I do not think so. Osmocote mentions oxide forms of NPK. In many regions soil acidification by chemical fertilizers is considered a problem, and fertilizer producers take care not to include acidifying elements in their products.

[Tomas]

1 hour ago, Phoenikakias said:

I do not think so. Osmocote mentions oxide forms of NPK. In many regions soil acidification by chemical fertilizers is considered a problem, and fertilizer producers take care not to include acidifying elements in their products.

There are only two potassium fertilizers, potassium chloride, a cheap source of that element, but containing chloride,  that can be harmful to sensitive plants. The other is potassium sulfate more expensive and used in the more valuable complete NPK fertilizers. The K2O oxide is simply a number to express the quantity of K.

https://en.m.wikipedia.org/wiki/Potassium_oxide

[Phoenikakias]

On 4/17/2025 at 7:59 PM, Tomas said:

All the NPK fertilizers contain sulfur, the potassium is there in form of potassium sulfate, but the fertilizer is not acidic, I think 

 

On 4/17/2025 at 9:51 PM, Tomas said:

There are only two potassium fertilizers, potassium chloride, a cheap source of that element, but containing chloride,  that can be harmful to sensitive plants. The other is potassium sulfate more expensive and used in the more valuable complete NPK fertilizers. The K2O oxide is simply a number to express the quantity of K.

https://en.m.wikipedia.org/wiki/Potassium_oxide

 

On 4/16/2025 at 9:01 PM, Jim in Los Altos said:

Yes.

True but it is also true that in some places soil acidification through the use of fertilizers is  consisered a problem and people there apply now and then also dolomite to counteract this effect or manufacturers take care to hold sulfur content low in their fertilizers. Compare the sulfur content in Palmgain with the one in an Osmocote type below. In latter sulfur quantity is less than half (15% vs 6%)

[kinzyjr]

I'm surprised Brahea edulis has been so vexing.  When I got a small one, I wasn't sure what to expect, but it has been trouble-free.

[Phoenikakias]

9 hours ago, kinzyjr said:

I'm surprised Brahea edulis has been so vexing.  When I got a small one, I wasn't sure what to expect, but it has been trouble-free.

I suspect that you live in a flat area rich in rainfall during summer (east coast pattern) if not throughout the year. My own garden is in a slope with xerothermic summer and less than 200 mm rainfall during the other three seasons. That is a considerable difference. Even if some palms are very tolerant of alkaline soils, I fear that their tolerance is not unlimited. I would rather compare my conditions to those of montane Colorado.

[Harry’s Palms]

On 4/15/2025 at 11:24 PM, dalmatiansoap said:

Any ideas how to improve anchoring? I don't know if it's problem with it's roots or might be something else? It's going good but still isn't well anchored after 7-8 years in the ground 

I never had a problem with mine . I planted it on a slope and it adapted quickly. As @Jim in Los Altos says very slow in the beginning but speeds up when it trunks. I have very rocky soil and it gets irrigation most of the year . Full SoCal sun all day . It is 28 years old. It was a seedling in a tube , strap leaf when it got planted. HarryI like that the trunk is self cleaning , leaf bases come off or fall off easily , revealing a large , smooth trunk. It holds a large crown of fronds . It could produce a fair amount of shade in the right location. Harry

[Tomas]

On 4/19/2025 at 11:52 PM, Phoenikakias said:

 

 

True but it is also true that in some places soil acidification through the use of fertilizers is  consisered a problem and people there apply now and then also dolomite to counteract this effect or manufacturers take care to hold sulfur content low in their fertilizers. Compare the sulfur content in Palmgain with the one in an Osmocote type below. In latter sulfur quantity is less than half (15% vs 6%)

Here is the answer by Chat GPT, I could not explain it better

Palmgain 8-2-12, looking at the composition of this fertilizer, it is stated : Sulfur 15.04%, 15.04% combined sulfur. What combined sulfur means?

Great question. When a fertilizer label says something like “Sulfur 15.04% (15.04% combined sulfur)”, it refers to the chemical form in which sulfur is present.

Here's the meaning:

• “Combined sulfur” means that the sulfur is not present as free elemental sulfur or in a simple sulfate form (like magnesium sulfate or gypsum), but rather it is chemically bound within other compounds—often in slow-release forms or as part of complex fertilizers (e.g., ammonium sulfate, potassium sulfate, or within organic matter).

• In practical terms, combined sulfur is still available to plants, but may require microbial activity or chemical breakdown to be released, especially if it's part of organic or slow-release components.

---

Why it matters:

• Fast-release sulfur (like plain sulfate) is quickly available but can leach easily from sandy or highly irrigated soils.

• Combined sulfur provides a more sustained supply over time, which is useful in long-season crops or ornamentals like palms.

So in PalmGain’s case, that 15.04% sulfur is probably included to improve nutrient uptake (especially nitrogen), aid enzyme systems in the plant, and provide a slow-release acidity buffer, helpful in alkaline soils.

If you're using it in containers or shallow beds, it’s good to be aware that the sulfur may act more gradually.

Does this mean the sulfur will significantly change the pH of the soil?

Excellent follow-up. The answer is: it depends on the form of the combined sulfur and the soil's characteristics, but generally:

Yes, sulfur can lower soil pH, but...

• Elemental sulfur (not immediately plant-available) is oxidized by soil microbes into sulfuric acid, which does lower pH, often significantly—but this is a slow process, taking weeks or months, and it’s microbially driven (so it works best in warm, moist, aerated soils).

• Combined sulfur in fertilizers like ammonium sulfate or potassium sulfate can also lower pH, but the effect is typically milder and more gradual—unless applied in high quantities.

• The impact on pH also depends on your starting soil pH and buffering capacity:

  • Sandy soils (low buffering) will acidify more quickly.

  • Clay-rich or calcareous soils (like in parts of Lazio) are more resistant to pH change.

---

In your case:

• If you’re applying PalmGain as directed, especially in pots or beds with organic-rich media, the pH shift is likely to be gentle and slow, which can actually be beneficial—especially for palms, aroids, and other plants that prefer slightly acidic conditions.

[Phoenikakias]

Nobody wants a rapid manipulation of soil pH, as long as plants already grow in that soil. Plants get shocked by such sudden pH change. I nearly lost three Sabal when I drenched soil with water soluble potassium and magnesium sulfates.  Besides alkaline irrigation water complicates situation further. Unless new problems arise in future, I stick to the advice of a very knowledgeable person, who suggested sulfur pellets and humid-fulvic acids.