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Water quality a primer

Horticulture 101 water.

Water quality is of prime importance.

If you live in the city and are a licensed business the water district is required to supply you with a monthly report on water quality with your water bill. This was part of the clean water act. You needed to request the report. Most locations the water quality changes from month to month and seasonally.

If you use a well, you need to test your water. About 1/5 the wells in the USA have high florid levels, this is more common a problem in the northern parts of the country.

Things to pay close attention to in the water report.

  1. pH of the water
  2. Hardness of the water.
  3. The type of hardness in the water. Calcium vs Magnesium.
  4. Sodium levels expressed in ppm. 

Why does this mater?

  1. Safer’s soap and neem oil requires a pH of 7 or less. At pH above 7 both have problems. Safer’s soap congeals at high pH levels. Neeme oil does not disperse properly at high pH levels.

  2. Your fertilizer was designed with a water pH of 7 and a buffering level of soft.

  3. If you where to add a fourth number to fertilizer it would be calcium. N-K-P-Ca. In soilless production calcium may be the number one limiting factor, for high total dry weight. I just watched a vendors video on the site and I am willing to bet a beer that the calcium levels are higher than most growers can easily achieve.

  4. Sources of nitrogen found in soluble fertilizers behave differently based on pH and temperatures of both the growing media and the water. Flash hot water heaters have come down low enough in cost to make them a useful tool in your water management practices.

If your water is alkaline you can use the hardness to determine the buffering capacity of the water is important. Your whole nutritional regime may not be what you think.

What can you do to change your hard water. If your water is very hard you may need to use phosphoric acid to reduce the buffering capacity of the water and the resulting high pH to as close to a pH of 7. A problem occurs here you have to account for additional phosphorus in your total nutrition. At Kansas City cut flower farms our water was so hard, we use to joke that it was like rocks coming out of the pipe.

If your pH is low you have an easier time. You can just pick a soluble fertilizer better matching your water.

If you want, I can help you figure out the titration of acid required and the adjustment to your nutritional requirements to maintain the same nutritional levels. Or we can work on a simple spreadsheet to do all fertilizer calculation. I know calculating ppm can be confusing. I know that calculateing the ppm of nitrogen sources can be frustrating.

You will also notice that the major supply houses sell injection heads designed for the use of food grade phosphoric acid. I used a dosmatic ceramic disk head on our first injector a mix tank followed by a dodmatic second injector, back in the day.

If your water is very poor you can look at large scale reverse osmosis. They have come down in price, to be cost manageable solution.

The low end injectors
High end injector

From the voices in my head


If you water quality is poor and you need reverse osmosis on a large scale. We are going to have to fined a specialist in commercial water quality. I have used Anderson reverse osmosis columns and storage tanks. It’s a pain but it is doable and gives outstanding results.

If you have hardness do high magnesium in your water. I am going to have to do research on solutions.

In northern Minnesota my water problem is magnesium.

Organic growers, need to pay very close attention to teas. Expecaly if they are home made. Problem can easily occur in the brewing process making it a challenge to accurately determine your N-K-P ratios correctly and actually. I have noticed with tea production that the forms of nitrogen get tricky. This may require a grower to do some advanced analysis.

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With glyphosate (carcinogenic in small parts per billion), and atrazine run amok even in nature, you definitely need to be purifiying water. Condensation recovery, which is essentially distilled water, can provide about half your water requirement, but should be run through a UV sterilizer for protection. Just verify it is 0 ppm TDS. If you’re using condensate pumps, then a little automation is helpful.

For high levels of hardness, antiscalant injection or a softener can protect the RO membrane from scale formation.


I have to pull some unbiased studies on glyphosate I have a very good source. If I remember from my organic chemistry days it brakes down to two carbon rings an bunch of oxygen, a phosphate and three sodium atoms. Glyphosate is easy degraded by sunlight so manufacturers now add a sun block into the product.

But let me get back to you on glyphosate mitigation. As I said I have a couple of good friends with to many degrees in there pockets and they are on nobody’s payroll.

One I know would have any real dirt if it exists.

From the voices in my head
Ethan Kayes

One more thought, the most toxic compounds are not man made but natural with exception of one plutonium. Richard Finemand.
The lowest level of input gives the best results.

I had a good friend who was a nuts and bolts organic farmer in Missouri. Horses not a tractor kind of guy. After he managed to poison he entire family with a witches brew in his truck garden. I came and help him get his farm back in order. Understanding he must be organic and green. No power. Kerosene refrigerator and freezer. He paid me in old laying hens. Cleaned, cold water processed. Koshered to my specifications.

Have a good night and I will get back to you next week
From the voices in my head
Ethan Kayes

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