A few comments, Blake:

1) I fully support your experimentation - hell, I do it all the time - but in this case I simply question the need.

2) 2 plants do not make a good test base. Even if they are clones, there can be sufficient variation in growth to completely overwhelm a feeding experiment. Last time I tried a comparison, I had a flat each (>50 plants per flat) of seedlings to experiment with under three conditions, and that was barely acceptable.

3) I still have to disagree with the mass versus weight percent thing. Density is irrelevant. Mass is constant, while weight is gravity dependent, but as you're doing your measurements in constant gravity, the percentages are identical. Mole percent is a totally different thing - and is not the same as mass percent - but you did not mention that earlier.

Fertilizer formulas are described in weight percent - in other words, if I have 1 pound of fertilizer, what fraction of that pound is nitrogen?

Questions about your blend:

• Is the formula 20% N, 20%P, & 20%K, or 20% N, 20%P2O5, & 20%K2O?
• What is the complete formula (in weight percentages)?
• What are the raw materials used to create it?

Agree with you, Ray! You must have had a lot of experience with your orchids.

Reader's Digest featured an article many yonks ago about the fact that if you take large rocks and break them up into near powder and then use them to fertilise the soil, it would break the back of the fertiliser industry. So, our natural soil is actually a whole lot of inorganic fertiliser from crushed rock (alluvium, say) as well as plant-based nutrients from natural decay.

Purists avoid "artificial fertilisers" meaning what was chemically produced through some process in a factory [imagining lots of glass bottles and tubes and boilers and vats, so that some chemical Frankenstein would result].

And if orchids want to be in the natural state they would be drinking up a cocktail of nutrients in rainwater, got from the mosses, lichens, bark and leaves rotting under their roots on a tree branch or a swamp. And a lot of people who are into organic farming imagine this would be much better, because it is natural.

As Ray might agree, a potassium ion would be a potassium ion whether it came from a natural source or a factory. And we would be quite shocked to know that common salt that we eat is sodium chloride, from two darn poisonous elements which we wouldn't dare eat -- sodium and chlorine. And that our tummies are full of hydrochloric acid. Not to mention the fact we keep burping out carbon dioxide, methane and lots of funny gases after a meal. So we are full of inorganic stuff, so why would we worry that the plants have them too?

I believe in the foliar feeding though, using Gaviota 63 to make the leaves, and then when the plant is sturdy, Gaviota 67 for making the plant to spike. Both are inorganic fertilisers.

Some scientists did tests and found that the underside of the leaves is more receptive to foliar feeding. I just spray a light mist to settle onto the underside of leaves and roots, and one squirt bottle can do the whole garden practically.

In this way, there is nothing to drip onto the pot medium. After the fertiliser has diffused into the plant, so you imagine, maybe a few hours later, the plants can be watered to wash away excess fertiliser before it dries and crystalises thus burning the plant when they get concentrated. In particular, the crowns (the small leaves that haven't grown yet) are susceptible to crown rot if the chemicals that fell on them are not washed away.

One rule in growing orchids here is to make sure all this watering and fertilising is not too late in the evening. When it gets dark, fungus grows in warm, moist, parts of the plant. So, the plant should be dry before dark.

I've also tried soaking the plants in a bucket of dilute Gaviota, at quarter strength, for hours. This is to see what fauna has accumulated in the pot. All the ants, bugs and even centipedes emerge and go swimming. All this can be killed by just putting a lather of soap on the surface, so the reduced surface tension prevent them from getting out of the water onto the bucket sides. The soap also prevents air entering their spiracles and they drown. [I hate to kill God's critters but I love my orchids more. So I fertilise and debug the plant at the same time.]

My objection to inorganic fertiliser is their tendency to get concentrated and cause chemical burns on the plant, which is less likely to happen with organic fertiliser. But, unless you eat your flowers, there is no need to make the plant organically grown in the pure sense of the word, so that you can attach a label to it with five numbers when you sell your plant and the first number is "9" like all your organic veggies!

One thing to keep in mind is that orchids required less fertiliser than, say, roses, and can last for months without feeding. However, those who are enthusiastic about getting lots of blooms have a rule (I read in a magazine) to feed everyday with inorganic fertiliser but at quarter strength. And to wash off the fertiliser with plain water a little while later. The nutrients won't leach out if you don't water for too long.

Other growers I know say there is a great difference whether they do their watering with tap water or with rainwater. A few growers catch rainwater from their roofs into a large tank to water their plants. I have noticed the difference in growth rates whenever it rains and when we use the hose to water the plants. They seem so much better in rain.

Commercial orchid growers with their clones under green shade netting spray their plants four times a day! They have the advantage of a sprinkler system, which I envy.

Just a few observations, which I hope might be helpful.

Some further thoughts on homemade fertiliser.

Would you believe that coconut water is used as a source of nutrients, growth hormones and so on?

Coconut water, and a slice of banana, used to be added to the agar in seedling flasks for germinating orchid seeds. Add this to our collected list of natural fertilisers!

Thank i might try the flat but i also want people to use it and see how they like it.

Mass and weight are the same thing I thought i was going crazy and I asked my chemistry teacher and she said I was right. And density is not irrelevant nothing is every irrelevant in chemistry. Moles are the only thing that are really truly constant as you can actually state a number to the amount of something base on Avogadro's number (6.0221415 × 10^23 for anyone who is wandering) I use moles a lot in calculation because they are the best way to make sure you have nothing left over.

I did figure out that fertilizers are based on weight doing a little research. So in this formula it will be a fifth as would be in any other fertilizer.

It is P2O5, & K2O. And the ingredients I use are guano(I live in a old house with bats; lotta this stuff outside), potash (My family has a wood burning furnace. I take the ashes and mix them with water. I then put this through a filter that takes out everything that hasn't dissolved, then evaporated all the water away and what is left over is potash.), Epsom salt, crushed bones and eggs (50-50), and dried molasses which I crush into a fine powder.

Yes i would! on one of my many other scientific ventures I made homemade flasking medium with these things and it worked very well but my little cousin wanted a better look at the plants so he opened the jar! I didn't see this until later and the whole jar was dried out and contaminated the plants were to premature to save.:(

Someone mentioned "Organic Fertilizer" earlier and in made me think of a lady in the "Orchid Society" who would only eat vegtables grown using "Organic Fertilizer".
It was a bit of a hassle at parties potlucks and the like.\
Then I notice that she used Potassium Cloride salt substitute because of hypertension. She didnt appreciate it when I pointed out that Potassium Cloride is often used in chemical fertilizers.

Just to clear up an apparent misconception, or perhaps merely a misuse of the words organic and inorganic. Chemically speaking, all plant fertilizers, whether they come from compost or a factory, are inorganic. Organic compounds are chemicals based on carbon, such as hydrocarbons (wax, oil, alcohol, ethers, many fragrances, etc.)

The important word to consider in this fertilizer discussion is "synthetic". As in those fertilzers manufactured in factories. While I agree that most people take the "all natural" thing too far, there is a valid point that the manufacturing of synthetic fertilizers is a major source of pollutants. It should also be said, for the sake of fairness, that any fertilizer, be it synthetic or natural, can pollute water systems if used improperly or in excess, which frequently occurs.

Personally, I prefer natural fertilizers because it is a better use of resources. Landfills are overflowing with decomposable material that could be used for fertilizer or biofuel or any number of other things. Humans, Americans especially, have become disgustingly wasteful. But hey, it's easier to throw a bottle or wrapper out the window of a car instead of keeping it til you reach a trash can or, FSM forbid, a recycling bin!

And yes, I do have a thread labled "organic fertilizers". Just goes to show how these ingrained misconceptions sneak in when we're not paying attention to what we are saying or typing. :blushing:

Yes, it is true that language is evolving and that the same words can express different ideas. In our present discussion we can get bogged down by semantics.

Organic can mean natural, as opposed to synthetic. And while I have done Inorganic Chemistry as well as Organic Chemistry with all those carbon chains, I won't hesitate to refer to all that lovely juices coming out of our compost as "organic" even if half of those nutrients are devoid of carbon atoms.

There's a part of me that loves what Blakee is doing. If, in a crisis (economic) nobody cares about orchids because we are all so darn poor we are growing our own food instead (a wartime situation!) we have to turn to devising natural fertilisers. So anyone who can do this is king. Let's put aside urine, which we were discussing as a source of urea. The quantity will never be enough.

This state of affairs actually happened to Cuba. This is where Blakee's inventions will be most valued. Poor Cuba was ditched as a trading partner when the Communists turned capitalistic and were fighting wars among themselves. Suddenly, nothing was coming into the country (Cuba). No oil, no energy, no raw materials, no food, no money. All of Cuba's motor vehicles (in fact anything that is motorised) came to a standstill. You had to walk and use bicycles. You had to rely of wind and water power.

So the whole nation had to farm, or starve. No fertilisers came in, so they improvised and did organic farming. Their health improved, and the rates of heart disease and cancers fell dramatically. They ate no meat (was illegal in fact) and became vegans. Only the tourists were served meat. It was a green miracle. No pollution, and the environment improved. Doctors without medicines from the drug companies discovered old folk remedies to dispense which worked.

In case you imagine that Cuba is now a paradise to live in, you're wrong. Unfortunately, foreign aid started to trickle in and cars and vehicles started plying the roads again instead of bicycles and bullock carts. Meat was again imported. People there are now getting sick again from all the ills of modern society - like the rest of the world which is committing slow suicide. Hey, that includes most of us! :shock:

Okay, back to the topic again, please. :biggrin:

Have spread a lot of natural fertilizers - shoveled it into a big spreader from the cow pens then pulled the spreader behind a tractor slinging it all over the farm, tractor,self then ate more Angus beef (the source of the fertilizer) at dinner than at any other time. I think that what a lot of people dont understand is that to make a crop or plant grow well you give it what it needs - no more - no less. Maximum yield or best growth is good as it feeds the most people and gives the best profit to the farmer -and the best flowers to the orchid grower. Waste and polution are in lock step. So some testing and a little science is in order. Unfortunately few take the time to really understand what they are doing and the result is the damage to the earth we are trying to preserve and no real benefit to the plants we are trying to grow. Organic fertilizers rarely furnish all the nutrients the plants need. It takes time to understand. Most successful farmers and commercial horticulturists are part scientist and are not likely to waste expensive fertilizers or damage the ground they depend on for their living.

Blake - if you are blending your fertilizer with natural ingredients, how do you know what your formula is? Guano, ash, molasses and the like are anything but standardized. (By the way, you reversed your argument on the mass/weight issue. Also, if it makes any difference, I have worked in the chemical industry for 29 years, after 4 in the ceramic products industry.)

You also miscontrued my statement about the density - it is irrelevant when comparing weight- and mass percentages, not irrelevant altogether.

Just because something is a nutrient used in seed- or protocorm culture, that does not mean it is good for mature plants. It might be absorbable, but when applied to media in a non-sterile environment, it might foster really bad stuff you didn't want, and might actually poison the root zone.