NPK fertilisers

[Tyrone]

I was talking to a good friend of mine who is heavily into organics, and he alerted me to the high concentrations of Cadmium, Lead and Mercury in a lot of NPK fertilisers. I had a look through many different fast release ferts available and they had Cadmium, Lead and Mercury in varying amounts. I couldn't find one that didn't have at least one of the three. All are poisonous even in low amounts and are cumulative. Some of the ferts had warnings in fine print, stating that persistent use could take the soil over the "safe" level. Most alarming was that these same fertilisers were advertised as great for growing fruit and vegetables, which you ultimately will eat. Lawn fertilisers even had higher concentrations.

I use quite a bit of fast release fert on my palms and was wondering why there is so much of these metals in fert and whether there is a fertiliser product out there which is heavy metal free. I like the "bang" you get out of these ferts, but I think I may have to look for an alternative. I already use a lot of manures, but I'm unsure if that is enough to keep everything going strong.

Has anyone else come across this one before???? I'm interested in your thoughts.

Best regards

Tyrone

[Kool]

HEY Tyrone,

I agree with your friend and prefer/use an organic fertiliser at home... in my opinion it will contribute to the plants health if you dont spoil them rotten...

[Keith N Tampa (ex SoJax)]

Guys, understand that manures will also contain heavy metals (sometimes in high quantites). Heavy metals are one of the biggest problems with the sewage sludge marketed for horticultural use. Most manure based products are not regulated in the same way (though sewage sludge is here in the USA). The reason there are heavy metals in fertilizers is because those elements are often found in the Earth where the raw materials mined for fertilizer are found. Processing the raw materials won't remove all of the heavy metals. By the way, some of those heavy metals are essential elements in tiny quantities. I'm not saying you should add them, just that living organisms often use minute quantites. Like everything else, it's the quantity that matters. Plants only absorb certain nutrient ions and they can't tell whether that ion came from an organic source, or a non-organic source. However, adding organic matter to the soil is a wonderful way to improve plant growth (and I practice it rigorously!). For the purpose of this post, I'm referring specifically to "carbon based organic material" as opposed to pseudeoscience used by groups that are trying to push society towards a lifestyle purportedly better for other life forms on the planet. Because of the poltical agendas of some in the "Organic" movement, it's often hard to have a discussion based on scientific fact. I find that incredibly disappointing because I beleive we could be doing much more to protect the environment while sustaining the human population if science were deployed dispassionately. Sorry for the passion in my response, it's just that the "Organic" discussion has become so polarized that science is dismissed and replaced with dogma (from both sides).

[sonoranfans]

One more reason to use humic acid, as it chelates heavy metals and prevents their buildup in soils. I would avoid the fertilizers with the heavy metals, and I will continue to treat the soil with humic acid. Its natures own heavy metal cleanser. Interesting that humic and fulvic(very similar) acid supplements also work in removing heavy metals from human beings as well.

Edited December 10, 2008 by sonoranfans

[Tyrone]

Very interesting info here guys, thanks for replying.

Tom I'm glad you've brought up humic acid. I've just been making up my own potting mix and had a big bag of Potassium humates and Magnesium in my shed which I put into my mix. On it's own the black powder doesn't smell like anything at all, but when I mix it into the potting mix, bark, blue metal and coconut coir, it instantly smells like the forest. It sounds like I'm doing the right thing then with this mix. The palms don't object at all. The chelating aspect of humic acid or humus is really intriguing. Could it mean then that if you increase the humus content of a soil with manures and compost that it will naturally chelate out heavy metals? The only problem with that then is it will wash the heavy metals into the water table.

Keith I may be wrong, but I thought that these three substances were not needed by the body in any amount, or is that part hype. I thought that the problem with lead for example is it looks like Zinc to most biological systems and gets absorbed like zinc only to become a spanner in the works which stops enzyme production. However if a plant can tell if lead is there and leaves it alone, we're worried for nothing.

Does anyone know if straight Urea with 46% N has any heavy metals in there? I would have assumed that Urea coming from an organic basis would have little or no heavy metals.

Keith I never thought about heavy metals in manure. It seems like they're everywhere then.

Best regards

Tyrone

[sonoranfans]

Very interesting info here guys, thanks for replying.

Tom I'm glad you've brought up humic acid. I've just been making up my own potting mix and had a big bag of Potassium humates and Magnesium in my shed which I put into my mix. On it's own the black powder doesn't smell like anything at all, but when I mix it into the potting mix, bark, blue metal and coconut coir, it instantly smells like the forest. It sounds like I'm doing the right thing then with this mix. The palms don't object at all. The chelating aspect of humic acid or humus is really intriguing. Could it mean then that if you increase the humus content of a soil with manures and compost that it will naturally chelate out heavy metals? The only problem with that then is it will wash the heavy metals into the water table.

Keith I may be wrong, but I thought that these three substances were not needed by the body in any amount, or is that part hype. I thought that the problem with lead for example is it looks like Zinc to most biological systems and gets absorbed like zinc only to become a spanner in the works which stops enzyme production. However if a plant can tell if lead is there and leaves it alone, we're worried for nothing.

Does anyone know if straight Urea with 46% N has any heavy metals in there? I would have assumed that Urea coming from an organic basis would have little or no heavy metals.

Keith I never thought about heavy metals in manure. It seems like they're everywhere then.

Best regards

Tyrone

Yeah, cadmium lead and mercury are nasty metals, but they are less active, toxicologically, in some forms. Mercury in an amalgam has been used in dental fillings, its not a real problem in that form, but as a liquid metal(old thermometers) its very bad for sure as it can be absorbed readily in respiration. The worst are the short chain alkyl mercury compounds, very toxic and they are difficult to remove from the human body. I expect that chelated mercury will not exist in a short chain alkyl form.

http://www.med.ucla.edu/modules/wfsection/...p?articleid=311

Chelation with humic/fulvic will help rinse the excess heavy metals away, and their uptake into plant roots is limited. Nutrients like Mg, Ca, Fe, Mn etc, are increased in their bioavailability by humic treatment, read this link if interested:

http://www.humates.co.nz/how

Yes you are right tyrone, the metals will end up in the water table. Water filtration(for drinking, cooking water) is a good idea right now, let alone in the future. As consumers, we can punish manufacturers who produce fertilizers with these metals by not buying them, and protect our palms from heavy metal poisoning(including even excessive levels of Iron) by using a humic acid soil treatment. Reading labels is a good way to excercise our responsibilities in keeping nature more safe from mans destruction. Im not sure if ANY living thing uses cadmium lead or mercury for an essential biochemical function.

Edited December 10, 2008 by sonoranfans

[Jose Maria]

Hi Tyrone and friends,

It´s OK to worry, but first the facts.

Urea and other Nitrogen sources do not come near anything that has heavy metals in it.

Potassium, is mined mostly from salt deposits , left by evaporated seas eons ago.. also from the Dead Sea...

With phosphorus there is a chance some unwanted elements get mined ( apatite source) but if the origin is remains of organisms in sea deposits, not much there but fossil bones ....

Now back to our palms: Of all NPK, they mostly need N and K, hardly any P.....

But..P is the most expensive ingredient,......salespeople are bound to push the one NPK fertilizer with the most P in it, even if the palms dont need it.....Same old story as with snakeoil....

If anybody wants to worry; here is some more to fret about....

Fertilizers are radioactive... yes, certainly, but nothing to stay awake at night .

In the UK organic farmers found out that the cattle dung they used for composting was laced with herbicides, that made their way tru the cow´s 4 stomachs, tru the compost pile ...and ...killed their vegetable patches.(weedkillers.....used to clean pastures)

I say: keep on using NPK, our palms love it.

[Bennz]

Does anyone know if straight Urea with 46% N has any heavy metals in there? I would have assumed that Urea coming from an organic basis would have little or no heavy metals.

bagged urea has a fairly high biuret content, which is ultimately poisionous. One of the commonly held theories amongst organic growers is that the high N fertilsers upset the C/N ratio in soil unless applied with a C source, and will therefore slowly reduce humus levels. So ureaformaldehyde or other N sources which include a C source are probably a better bet.

[Keith N Tampa (ex SoJax)]

Tyrone, we are still understanding the way biological organisms work, so we still find new discoveries. Not long ago, Nickle wasn't considered essential, but now we know it is. One of the key problems is we havn't had the ability to test for these metals in extremely small quantities (which partly explains why we didn't know some of these heavy metals were present in fertilizer sources). As we've developed the technology to do so, we make new discoveries. Though toxic in excess, even Selenium is essential to some plants. By the way, I agree that Nitrogen is very unlikely to contain heavy metals in general. Unfortunately, my syntax in the above post was pretty bad! I don't know absolutely, but I suspect you are right about urea not containing heavy metals though most is actually manufactured from Natural Gas (which is chemically organic because it contains carbon). However, Bennz is right about the biuret content in some urea sources. However, not all urea sources contain high levels of biuret. I also tend to agree that with Bennz that the high Nitrogen fertizers have the potential to reduce humus and that is why I believe in enriching soil with organic mulches, yard waste and compost. However, I really doubt the C from Ureaformaldehyde (or any of the other forms of N that contain C) would correct the humus reduction associated with a High Nitrogen fertilizer regime. Stick with the organic matter and you won't go wrong. Jose Maria mentions P being expensive, and he is right. However, fertilizer salespeople won't universally push extra P formulations. In fact, it can be very hard to purchase in large quantites. Thus, many are focusing on increasing the efficiency of P fertilizer and greatly reducing the amount applied by applying a coating to it. Coating fertilizer can increase target plant uptake dramatically which conserves resources, and protects the environment. Sonoranfans mentions that he doubts any organism uses Cadmium, lead or mercury for an essential biological function. He may be right, but that's a bit too absolute for me. Like he suggests, I do filter most of my own water, however I really do that to remove the Chlorine flavor that comes in the municipal water. Also like him, I am very interested in how Humic acid improves plant growth. He isn't the only person I've hear extoling it's virtues and some I've heard are commercial agriculturists which adds weight to his assertion. Conversly, the sustainable population of Earth is considerably less if all food production is limited to organic techniques. Thus, we come to the ultimate trade off: how many die if we switch to wholly organic techniques vs how many die as a result of the imperfections of using synthetic fertilizers. It really wasn't until synthetic fertilizers came along that the population of the Earth exploded. Therefore, I conclude that they've been a net positive for the human species. In my yard, I will continue to feed my palms by increasing organic matter in the soil and applying coated fertilizers at appropriate rates so that I can apply less, pollute less, and meet the needs of plant. I'll also try hard to be humble and keep an open mind while I continue to learn!

[Tyrone]

Thanks guys for all your comments and the links. They've given me a lot to think about and I've learned a lot too.

Best regards

Tyrone

[HKO2008]

Dear Tyrone,

The best palm feeding for me has been organic lawn fertilizer, because grass has basically the same needs as a palm tree, how strange this may seem. Both are foliar plants. The lawn fertilizer i use contains Mycorrhiza. Mycorrhiza attach themselves to the roots of your plant/palm and extend the root system and make ingredients better available for the host plant. It doesn't do any damage to your plant, it just happens to help them.

Henri

[Kris]

Hi Tyrone and friends,

I say: keep on using NPK, our palms love it.

Yes,Jose even i have similar opnion ! And i used here manure from cows,goats the result is not much on our palms but the crotons & pines,hibiscus plants love it.

But i have been using D.A.P for some time,leaves were green but no speed in grouth.recently i was curious to use Coconut palm mix fertz,believe me i do not know what is the ingredients but the palms for the very first time showed signs of speedy grouth and the agro fert dealer asked me how old is your coconut palm tree,i told him its 25 years plus aged.he wrote me a slip and i went to the delivery counter their the stuff mixed few chemical based fertz in a certain ratio and said it does even have micro nutrients in it.

as soon i came home i dug few holes and filled this fert around my p.sylversteris & other palms like P.Rupicola etc..all showed phenomenal grouth in around one month time without any burn effect..?

I have no intention to switch back to organic manure,since it brings with it lots of worns & bugs that are visible during damp season & our pets(dogs) seem to eat this manure and fall sick !

And white nylon kind of roots are seen around all the phoenix palms & those in pots roots have come out of their containers.. The effect is like a herculas awakening or as the palms similing like the mechilin tyre company logo !

i.e what steroids does for human body builders,this fert does for palms,especially for the phoenix palm species.

Love,

Kris

[Jose Maria]

Hi friends,

First of all...Kris could we get a look at your secret formula.? We all kind of know what our palms need, ...but the details ....?

I certainly dont want to point a finger at all salespeople, but here where Ilive... I ´ve seen it happen....no harm done to the plants .. only to the buyers pocket.....

Coming back to Nitrogen: in many studies done in the tropics, no organic fertilizer realy improves growth ...because of lack of N.

N is so low in compost , etc... that the soil bacteria have to "keep N from the roots of the plants " to be able te "digest the organic matter".If we want organic matter to work, we need to add a Nitrogen source to it.

Here I live surrounded by african oilpalm plantations, and you can clearly see if a farmer does´nt fertilize(with NPK).

His yield goes down, and his plantation is full of sunlight, the palmfronds are thinner....

But...the price of NPK is so high now, the price of palmoil is down....everybody is using less fertilizer now.

Benzz: New Zealand is outstanding for the way it cares for the environment,but with all due respect, biuret ( a herbicide) is present in Urea, but it will decompose into urea in the soil...the benefit from Urea is larger than the damage from the herbicide.

Keith;I agree 100% with your outlook. Lets not go so far as to think NPK fertilizers are some kind of toxic waste...full of lead and mercury, etc... thats only fearmongering.........

The recent scare ( and deaths ) from "organic "spinach in the states should remind us that "organic ", "pure", etc...do not neceseraly mean " innocuous". Organic matter can also harbour all kinds of surprises!

Conclusion; organics and compost work if they are accompanied by nitrogen.

[Tyrone]

Jose, I'm going to search for an NPK fert with relatively low heavy metal readings and mix it with humic acid which should chelate the heavy metals out. I will also manure and compost heavily to build up the soil. I may cut back a bit on my NPK and focus more on Urea applications with humic acid that already has Potassium and trace elements already complexed into the mix. Currently I'm basically doing that, but I'll up the humic acid content. The humic acid in my potting mixes seems to be working exceptionally well. I can see the dark green change moving up the veins on some of my palms only a couple of days after repotting them into it. Humus is King in the garden.

Best regards

Tyrone

[alan.oz]

Tyrone, those humates sound great

Can you please provide more information - brand name etc

[ariscott]

I fertilise everything with organics and find them as fast... maybe because I am in the tropics, I am not sure... I am a firm believer that if you improve your soil with organics, the growth will come with it.... Maybe they don't grow as fast as if I fertilise with inorganics, but I can't complain with my palm growth so far. My tree thrives too with a lot of organics... my fruit trees appreciate it and my soil is loving it!! You should try and see the difference it makes to the soil...

Regards, Ari

Edited December 13, 2008 by ariscott

[Tyrone]

Tyrone, those humates sound great

Can you please provide more information - brand name etc

Hi Alan,

Here's the link to the humates I've been using.

http://www.nutri-tech.com.au/products/huma...nitro-k-70.html

Best regards

Tyrone

[Central Floridave]

How does the cliche' go?

Feed your soil not your plants.

good info on this thread thanks.

[Jose Maria]

Hi friends,

In Costa Rica too we use humic acids with good results, it´s produced here and sold as a liquid.The farmers spray it with apparently such results they are inclined to cut back on the classic NPK fertilizer.

Here we can use the cliche, since the soil ends up with less and less nutritive elements......if we dont put back what´s harvested.

Ari, I saw a video on the Darwin Botanical Garden, (In Palmpedia) and was glad to see some american palms growing there! I believe your climate is a lot like here in CR.

Regards.

[ariscott]

Ari, I saw a video on the Darwin Botanical Garden, (In Palmpedia) and was glad to see some american palms growing there! I believe your climate is a lot like here in CR.

Regards.

Hi Jose,

Darwin is dry monsoon tropics. We have long and dry dry season and very wet monsonal rain in the wet. A little extremes at times... but with additional watering in the dry, the plants don't mind...

Regards, Ari

[Turtile]

Organic material that has a large C:N ratio will actually lower the amount of nitrogen available to plants. Soil organism are made up of N. When you have a lot of soil organism, the organic matter also disappears. The organisms send off CO2 (respiration).

Its best to use both organic and inorganic fertilizers. Organic material improves the soil structure. It is capable of more negative charge which means it can hold more nutrients. However, NO3 is negative which will leach through. NH4 will stick. If the organic matter is too acidic, the H+ ions will fill the spots and therefore limit the amount of nutrients that can stick to the soil(can add lime to fix). Another good thing about organic is that it releases nutrients slowly to the plants. Although organic has many positive attributes, it has a few problems. The ratio of nutrients is usually not correct for the soil (crop). This can lead to excess nutrients which can pollute. Organic fertilizers are so low in nutrients, you would need massive amounts in order to fertilize a crop.

By using a mix of both, you improve the soil and us the right amount of each nutrient. The other thing to remember is that organic isn't free from unwanted material.

There is usually enough P in soils, its just not available to the plant like other nutrients. Mychorizae are very helpful for plants since they can help them absorb P.

[_Keith]

What a great thread. Keep it going.

Here I blend both organic and inorganic. Because I have noticed organic methods takes a couple of years to really start to affect things, I always use something like Osmoke and Root Stimulator on new plantings. I then start an organic program for the most part, but I do supplement nitrogen in the spring when plants here make most of their growth.

I also believe that the effect of organics is as much or more on the soil structure as on the actual nutrients. In other words, it is not so much about the nutrient content of the compost and mulch, as it is conditioning of the soil to allow the plant to uptake more of the nutrients that are already and have always been there, with the exception of nitrogen that is.

[Jose Maria]

Hi Turtile and friends,

Very well written synthesis . I could not have done it better. This resumes all of the questions that arose in this post.

Farmers here are looking seriously in organics now that (chemical)fertilizers are so expensive, but they run exactly in the kind of situation and problems you mentioned.

Depending on local factors, the solution will probably be a combination of both organic and chemical.

And that includes us , the palm - enthusiasts.

Regards.

[AggiePalms]

There are some major environmental problems with using high concentration inorganic fertilizers. First, while they do produce artifically rapid growth in palms in your yard, only a small percent of the fertilizer is taken up by the plant. Most of the highly soluble NPK is rapidly leached from the soil and carried away from your property to a nearby creek or wetland. This slug of excess nutrients leads to rapid destruction of the native wetland or aquatic species and replacement by algal blooms, which when the algae decays, leads to low water oxygen conditions and loss of the native plants, fishes, etc. A very high price to pay...unless your only interest in the environment is the unnaturally rapid growth of the palms you happen to own.

I see this process happen every day. I live a few tens of meters from a large pond, and only hundreds of meters from the salt marsh. All my neighbors use excessive inorganic fertilizers, and over the past few years runoff has nearly killed all the fishes in the pond as well as the brackish the marsh grasses, the nursery of the sea. The pond is now a stinking, algae filled hole that no neighborhood kid will swim in. Is that a good tradeoff, spending too much on unnaturally high concentrations of nutrients, to see it wash into the aquatic ecosystem and harm it?

I use two types of fertilizer: Mulch from composted leaves that drop from my trees (which contain all the nutrients that the trees take up from the soil naturully). In the spring, the trees take up the nutrients from the soil and grow; in the fall they drop the leaves (nutrients). If the mulched leaves are allowed to remain, the trees pick up the nutrients again in the spring and grow, year after year. No cost, no waste, no pollution. Natural recycling, as has happened since the first trees grew on Earth. Secondly I use a targeted, very small amount of slow release organic fertilizer only on my palms and other tropicals. But only on these, not my native plants or grass.

Guess whose yard in my neighborhood is the greenest, healthiest, and looks the best, even during droughts and major freezes? Do my plants grow without inorganic fertilizers? Some call my yard "The Jungle".

[sonoranfans]

Jose, I'm going to search for an NPK fert with relatively low heavy metal readings and mix it with humic acid which should chelate the heavy metals out. I will also manure and compost heavily to build up the soil. I may cut back a bit on my NPK and focus more on Urea applications with humic acid that already has Potassium and trace elements already complexed into the mix. Currently I'm basically doing that, but I'll up the humic acid content. The humic acid in my potting mixes seems to be working exceptionally well. I can see the dark green change moving up the veins on some of my palms only a couple of days after repotting them into it. Humus is King in the garden.

Best regards

Tyrone

Tyrone, the humic acid/humates/fulvates, have a number of functions. First is cleansing of the soil form salts/heavy metals. This is great for potted palms that may accumulate salts, mostly due to watering and also some accumulation can be due to the use of NPK fertilizers which often contain salts. I have observed the visible removal of salts on the surface in a number of potted plants/palms over the last 2+ years, and the palms also showed their appreciation in lush growth. My potted palms do not have any visible white salt crystals even though I use tap water on them. Second, the humic conditions the soil for beneficial microbes that are critical to strong root growth. Third, they represent the final decomposition product of compost, so the humic feeds them. Fourth, the humic chelation of essential minerals temporarily traps and slow releases the essential minerals as the non chelated ones are consumed. I dont use alot of NPK fertilizer. I use fish emulsion, humic acid, and add some NPK (hand)broadcast 2-3 times during the growing season. I no longer use NPK spikes. I used to use alot of NPK, and no Fish emulsion. As I switched over this year, and also increased the humic acid application, the yard took on a nicer "glow". NPK fertilizers have gone up in price since they are used so much in the corn/ethanol subsidization here in the USA. This has reduced the price difference between NPK and the fish emulsion, and all my indications are that the fish emulsion works better anyway. My soils dont drain very fast, and it only rains 8" a year here, so I dont have the soil rinsing/delpletion of minerals and nutrients issues that say a sandy soil would bring. I might spend alot more on fertilizer if I had sandy soil.

Edited December 14, 2008 by sonoranfans

[Jose Maria]

Hi Aggiepalms,

I read your post with atention, and I certainly agree with you that all of us have a commitment to protect wildlife and the environment.And pollution of swimming holes and lakes is cause for concern....

However for the sake of discussion, using the words natural and unnatural take us in the realm of dogma and irreconcilable extremes....

Where does nature end ???....and does the unnatural start??

An example ; most of us use a toilet, with a septic tank attached, which does some groundwater pollution of its own...(= unnatural)

But here where I live, in the south of Costa Rica, there are areas where people prefer to "take care of their needs", behind some bushes....(seems more natural...)

This of course is the source of all kinds of diseases related to the digestive tract..( are these diseases natural?)

To remedy this situation the Ministry of health builds free toilets, unfortunately it takes a lot af convincing to get people to use these.

People take care of their toilets, but dont use them....Why??---another detail.. they dont like toilet paper, they prefer the "washer" tradition....(more natural??)

I prefer to leave some question marks hanging in the air.....

[Tyrone]

Thanks guys, there's been some really good discussion here. I think anything we do here has some impact, and what will impact the environment adversely in one area may not impact adversely in another area. I suppose if we want to be responsible we should look at the area we live, what soil/ drainage issues we have, and act responsibly.

I live on sandy soil, and do have to build it up a lot. I try to use as much organic material I can get my hands on, and dig compost holes around the garden. I don't think much of my fert application reaches the ground water because I've planted so heavily that my whole back yard is now a mass of feeder roots. I found that out on the weekend when I planted out some Cyacs thouarsii's. The area I planted them has never been deep watered and was alarmingly dry deep down, whereas about 6 months ago I dug a compost hole in the area and it wasn't as dry, so the conclusion is my plants are catching everything before it gets too deep, but that's what rainforests do anyway. Other areas would be wetter, but my plants are hungry little things and I doubt much gets down too far. Syagrus and Ravenea rivularis are incredibly hungry, and I don't fert the Syagrus anymore so their roots go far and wide scavenging "stray fertiliser", and they're still growing fast fat and high. Ravenea rivularis is so hungry it doesn't even grow weeds around the base. In fact I almost never weed my rainforest anymore, largely because of lack of sufficient light, but also due to lack of excess nutrient.

If my garden was on the edge of a waterway etc, I would be very careful in how I fertilise, but, if my garden was hungry it would take up most of what was available even then, and if the waterway had good clean water, the roots would get into the waterway and help clean up the waterway by sucking up excess nutrient. In fact I wish I had a natural stream running through my property, because there are so many palm species I'd plant on the banks to help with soil erosion and catching excess nutrient, and the palms would look fantastic.

Best regards

Tyrone

[Jose Maria]

Hi Tyrone and friends,

For these discussions are the reason we come to this site in the first place. I´m glad we can discuss and exchange knowledge.

I may not seem to be a fanatic about environment, but I know the subject, by the way, I read a book by a fellow australian about "Permaculture".

Most people here in Costa Rica are also acting responsably regarding the environment.

It is not the same to apply NPK fertilizer in a dry climate like West Australia, where salts could build up, and here in Costa Rica where it rains more than enough for most crops.

The city of Perth itself I imagine to have a mediterranian climate ,which determines you can succesfully grow lots of interesting palms, like the south of Spain?

Just so we dont forget its all about palms. I´ll upload this picture of a Licuala elegans, from close to where I live.

.The lady is the owner of this farm and has a nice colection of palms.

Saludos!

[Bennz]

I think also another issue is climate. For growers like myself in temperate climates it is usually better to ensure sufficient pH and Ca levels (ie lime) to get up to the point to make earthworms as happy as possible, as worm castings concentrate minerals so much. Usually in my country 1000kgs/ha lime will add more N into a farm than 1000kg Urea/ha, because of the impact on soil life.

N-fixation from free living soil bacteria can be significant too, as also from lightning, some rainfall conditions, etc etc etc.

Some of the tropical farmers are doing incredible things with legume interplanting, which can add large quantities of N and C organically. It would be interesting to see what your oil palm plantations looked like with Inga or Leucena interplant, and Velvetbean (Mucuna) understorey. Not convenient in monocultural plantations, I know!

[Tyrone]

Jose, Yes you are right. Perth has the typical wet winter dry summer regime of a Meditteranean climate, but according to the Koeppen system of climate classification Perth and the Swan Coastal Plain is at the bottom of the dry subtropics. You really notice the difference in temp just driving out of the hills from the south onto the coastal plain. The evaporation rate is much much higher than rainfall, so if you want to grow anything more than a cactus garden, or a pure native garden you must irrigate. High NPK use and low soil moisture leads to salt buildup which would ruin a soil. Here in my garden I rely on good water retentive soil and mulches and irrigation. Along with a canopy I have everything I need to grow my rainforest.

Bennz, it sounds like NZ soils are quite acidic for lime applications to release nutrients. I saw the same thing in the south of England. Just add lime and everything greens up. It won't work here though, especially along the coastal strip where you can't dig a hole without dynamite and the soil has a pH of 9 or 10.

Talking about beneficial bacteria, I once innoculated my garden with beneficial bacteria to catch nitrogen from the air. I used a 1Litre bottle which was meant for 10000m2 on my 600m2 garden. I can't say for certain if it did the trick, but people ask me what my Syagrus rommies are, because they're so big they look like another species.

Best regards

Tyrone

[Jose Maria]

Hi friends,

Yes BENZZ, many oilpalm plantations are interplanted with Mucuna,it takes care of the weeds and will add some Nitrogen. But once the canopy of palmfronds closes in... no more weeds or anything else.

Well, if you fertilize with NPK , otherwise your canopy lets the sunlight tru and this causes grass to grow... As far as pH is concerned, most oilpalm plantations dont need any Calcium added. Most calcium here is applied in the coffeefarms, where coffee grows on acid volcanic materials.

As far as earthworms are concerned, farmers that have cattle use the manure to grow "Californian reds", and then sell the castings etc.. as fertilizer.

But beware , when deworming your cattle,...that manure is toxic to earthworms!

Tyrone,I also have an anecdote to tell about bacteria, a friend asked me what happened to his Zamias, the roots came out of the ground around the plants. I recalled having read about the corraloid roots, full of cyanogenic bacteria, and yes , there they were!

Some investigation is done in Costa Rica on "mycorhizas", to mprove absorption by the roots, anf it seems to work!

Saludos!

[_Keith]

One of the biggest issues is that most of the research for fertilizers in done on producing farms. This is a vastly different environment than the average palm gardener's property.

[Tyrone]

I think the Nitrogen capturing bacteria are Azobacter bacteria, and there are many species of bacteria which do it. Cycads are the only plants on earth that farm this bacteria along with the blue/green algae in there corraloid roots, so they are more able to grow on impoverished soils. The Macrozamia's which grow in the wild around here are a testimony to that, growing on sandy soil with very low organic matter but always green, or blue which ever genetics are in the plant. It's amazing stuff that should be looked into much more for use in large scale agriculture. I think that one bottle of innoculant I used on my garden was equivalent to using hundreds of kilograms of Urea every year. It would be interesting to find out if they're still in my soil. They do need iron and organic matter in the soil to do their nitrogen fixing thing as well, so just pouring it onto sand will do little. Luckily my bore water has a healthy amount of iron.

Best regards

Tyrone

[Jose Maria]

Hi Tyrone ,

Even when the soil is fertile, the Zamias here( we only have 2 species in CR) put out their Corraloid roots.Of course, if there were a lack of nitrogen, they could fix it....

Yes, I agree with Palmarati, ..a few "backyard palmgrowers "is something very different from "farms", and we are not going to pollute the water resources.

I read about the Gulf of Mexico , off the Louisiana coast, being killed by pollution from the farming in central USA, and fertilizer playing its part in it.

Or are there any other aspects we dont know about???