Fertigation and acidification?

[Darkman]

Anyone using Fertigation or acidifying through their irrigation system?

[WillsC]

Yup. Let me take a picture. The horizontal barrel to the left has 96% sulfuric acid in it, basically 3X as strong as what you would use in a battery. The blue barrel full of water has 60 gallons of water and 18 cups of acid in it. The trashcan is 33 gallons and has 9 cups of acid in it and 12 cups of ammonium sulfate.

I hit them with the fertilizer acid mix once a week and the other 1-2 waterings are just the acid water.

There are two different venturis plumbed in so I don't have to water all 3 beds at once if I don't want to. I can run the water through either venturi or bypass them (as it is in the picture). The red dial lets you fine tune how much acid water is drawn in to the line. If the PH meter shows the PH of the soil is going up you turn the dial up from say 3 to 3.5 and the PH of the irrigation water falls from 5.0 to 4.5, it is just that easy.

Venturis can be tricky to get to work but once you have it set up it works flawlessly. That bottom venturi (black one) supplies 7 impact sprinklers with PH 5.0 water. It will draw with 6 impact sprinklers running but with 5 impact sprinklers the venturi does not work, won't draw so like I said it takes some dialing in. The smaller orange venturi will draw with 4 impact sprinklers running OR just a garden hose with a full flow nozzle. The black one won't draw with just a hose running so that is why the orange one was needed. I also have a 1.5 inch venturi but it won't draw even with 7 impact sprinklers running so like I said some experimenting is needed.

I had just filled the barrel Sunday to the rim with the acid water mix and the 7 impact sprinklers ran Monday for 90 minutes and you can see how much acid/water mix it drew up from the barrel. I only have to refill that barrel about once a month.

I also have a 300 gallon water tank (a tote) with a 3/4 horse well pump mounted to it so I can pump out fertilized water to the irrigation lines which go to every plant on the property. The micro spray heads don't draw enough to make the venturis work. I have the tank plumbed so that I can make it go to any of the 12 or so irrigation runs on the property. It was a lot of work to bury all the lines but makes my life so much easier now.

[Darkman]

Sorry for the delay but I was out of town yesterday in Poplarville MS at a tree grafting clinic. I am running the micro sprays (surface irrigation) like Hershel has but I am running quite a few of them (around fifty of them) and I use a 1 1/2 supply line from the 1 1/2" valve so maybe there would be enough flow to work the venturi. I suppose there are smaller venturis that I could get? If not I could hook it up to the overhead sprinklers that I will run once a week.

Did the acid purchase require a license?

Do you have an agitator in the one with fertilizer or is it soluble enough that you just stir it in?

I need to hook up with Hershell and come down for a visit. I'm sure there is a lot that I can learn from you and your place.

[WillsC]

I don't think you will be able to get the venturi to work with micro irrigation no matter how many of them you use.......it isn't just the volume of water but how quickly it is moving. If say a garden hose was releasing 4 gallons a minute and that made the venturi pull if you had 100 micro sprinklers also releasing 4 gallons a minute collectively they would not make the venturi pull. Why? I have no clue

Yes there are smaller venturis but that will not solve the problem. I tried it using my micro sprayers and no matter how many runs I tried I could not get the venturi to draw. I will be curious to hear if you have different results. For the micro sprayers I have a 300 gallon tote with a 3/4hp well pump mounted on it and from that tank I can fertigate any of the sprinkler runs in the yard.

Sulfuric in Florida does not require a license. It is HEAVY.....the 96% acid barrel weighs over 700 pounds, almost twice as heavy as the same barrel filled with water. The acid is thick, like baby oil which actually makes it safer to use as it does not splash as easily as like the 33% acid. I have a tractor with a front end loader to move it but I still did not want that much acid horizontal so I bought two more 55 gallon blue barrels and broke the acid up in to 3 barrels. Figuring out how to siphon it from one barrel to the next was also interesting.

I don't have an agitator, the ammonium sulfate is completely water soluble, melts like sugar instantly on contact with water. I don't even stir it up before using it though perhaps I should.

[Darkman]

Great information. Somewhere there should be some technical data on the venturis that would address pressure, flow and viscosity numbers to achieve satisfying results. It may be the post and pre venturi pipe must remain small for a certain distance to achieve good steady velocities.

That is very heavy. No tractor here so I'll have to consider smaller batches. I must get some soil testing done to see where I am. I know my soil is acidic but not the actual number. The guy that put in my well stated that from his experience my well water may be as low as 5.0 Got to check that also.

Good to know about the solubility of ammonium sulfate.

This may be an idiot question but should all these containers be shaded?

My suggestion on moving the acid is a magnetic drive pump. Little Giant is a brand that makes small ones that can handle acids and alkalis.

[WillsC]

Charles,

I don't think it is the pipe before and after the venturi, though could be. With the venturis that go on a hose bib they work with a hose less than 50 feet but 100 foot hose they won't work. You will just have to try it and see, should be interesting. For me it went from an interesting challenge and trying to make the venturi do what I wanted to finally giving in and letting it do it it's way.

If your well water is truly 5 PH you won't need acid.

No need to shade the containers. The bushes want full sun and it does not seem to bother them if the pots are in full sun also. Mulching the tops of the pots is a good idea and also using larger pots. Unlike most plants where you should up pot in stages gradually there is no need to do that with BB.....put a 1 gallon in to a 30 gallon pot? No problem. The soil though can NEVER get dry, in full sun that may mean daily or twice a day watering depending on pot size.

The pump is a good idea if it can handle the concentrated acid. Even if it states safe for acid it may not be safe for concentrated acid. The picture above of the acid barrel of mine? The bron valve on top said safe for sulfuric acid........the acid ate it in less than a week and would no longer open. The bottom valve has been better lasting a year but you still can't open it with your fingers.

[Gina]

Did the acid purchase require a license?

Maybe you can start with battery acid purchased at an automotive store. It's 33% and comes in two convenient sizes - 6 quart and 5 gallon and is relatively easy to work with. I 'only' have 60 or so plants in large pots (+/- 15 gal), and that much acid lasts a long time.

I use one of the small hose-end siphons, and don't use the acid solution every time and my plants do fine. About once/week. I would if I have the set-up Wills does. My 5 gallon acid 'box' is well into its second or maybe third year. The 6 quart size would last a year or so, but when I was using those, I didn't have as many plants as now.

I do stir my ammonium sulfate. When I pour it into the water, I can see some crystals in the bottom - but it dissolves extremely fast with just a swish or two.

[penandpike]

Wills I don't see any filter on your venturi. Is it at the bottom of the tank? If you try to operate with lets say the orange venturi what do you change in the sistem (which water tap you open or close and how much you open or close it?)There is someting odd in this set up. Also why you don't fertilize the BB with each watering insted of once a week? What is the fert. concentration (nitrogen ppm) when you fertilize once a week?
All venturi problems can be easily solved if it is replaced with a proportional injector like one of those;

http://www.qcsupply.com/commercial-industrial/horticulture-greenhouse/injectors-medicators.html

I did use venturi in the past but with all those problems that comes with the set up and the constant changes in the water flow I did change it with a proportional injector. I burnt and kill many BB bushes when one day My venturi set up got crazy and some concentrated acid sliped into the sistem.

[WillsC]

Pen,

Yes filter is at the bottom of the tank.


Injection pump $500....Venturi $14 Remember you are a commercial grower, I don't sell blueberries.

This is Florida so we get a lot of rain, in summer a lot of weeks it will rain an inch of rain 5/7 days. Some weeks the only time I water is the fertilizer and rain takes care of the rest. If I fertilized with each watering and it rains all 5 days I am either wasting water or under fertilizing.

The frying bushes is why I dilute the acid in to 60 gallons of water. Once you dial the venturi in it is flawless. If say a impact sprinkler clogged the ph of the water going to the bushes would go up as the draw would be reduced. The only way the PH would go down is if the flow increased and that is not possible unless say a irrigation pipe burst but that is a very unlikely issue.

What do you find odd in the setup? The plumbing above shows 6 valves. One is simply used to fill the barrels, there are two pipes I can insert to hit either barrel. All valves when in use are always 100% open. The fine tuning of the acid mix is done with the small valves connected to the siphon lines on the venturis themselves.

Very bottom valve (blocked partially in pic by dial from black venturi) is a bypass........if that valve is turned on which it is in the picture the water just goes threw it and bypasses the venturis. If I close that bottom valve and open the two to the black venturi the water passes through it. Same with orange. Honestly I could just leave it always on the venturi because once I shut the 7 impact sprinklers off it does not matter what watering I do none of it pulls enough volume to trigger the venturi to draw the acid water anyway.

[penandpike]

If you are saying that all water flow passes through the venturi and then goes to the sprinklers, then this is a very wrong way of using the venturi.
A small size injector that will be ideal for you is around 200$

[penandpike]

Wills
how much Amonnium sulfate you use each week for one BB plant.

[WillsC]

If you are saying that all water flow passes through the venturi and then goes to the sprinklers, then this is a very wrong way of using the venturi.
A small size injector that will be ideal for you is around 200$

Pen,

The small injectors will last a couple seasons then fail......not to mention why use the pump when the venturi works perfectly and will never fail as there is no moving parts.

Yes all the water going to the heads goes through the venturi, please explain why it is "very wrong" as it works flawlessly. I have had this system running going on 3 years now and no problems at all. The only drawback is, due to the restriction that makes the venturi function in the first place it reduces the flow but I only have about 400 bushes and the amount of flow I have from an above ground 1HP well pump easily runs the 7 impact sprinklers that cover those 3 beds. Now if I had several acres of berries then yes I would plumb the venturi in so it was only in an arm of a larger piping system and most water would bypass the venturi BUT as you have found out that type system can lead to problems. As long as the flow you need to have is ABLE TO pass 100% through the venturi it is a perfect system. If it fails it fails OFF so worst case scenario the plants get high PH water which won't harm them not PH 2 water which will kill them. Remember this is a hobbyist site, not commercial so we are not watering a dozen acres of BB with 20 HP pumps and 10" piping

I have no clue how many PPM of nitrogen the bushes get. I would say the 400 bushes across 3 beds get about 12 cups of AS a week. Doing the math I guess that works out to 1.4 teaspoons per plant per week? There is some over spray that would be loss so I would guess they get about a tsp each per week. The plants grow great, the mature plants are over 6 feet tall even with a end of May prune of 30% off the tops. Are they a bit over fertilized.....probably. I will cut back once the younger bushes are mature.

[penandpike]

Wills
You said it. Very wrong for me is the restriction of the water flow and may be overloading the 1hp pump. But if the amount of water is enough for running the sprinklers I will cut it down to just "Wrong" And after another thought I'll say it is just "Fine" if it works which is the most important thing. I really never thought that so much water can pass through such a small hole. May be now I will make one big venturi for me and get red of my proportional injector which as you said sometimes breaks. Now just to make little contribution to this very important topic here is a very simple filtering for the venturi. Just a piece plastic mesh inserted into the sucking hose.

[WillsC]

Pen,

I do have a larger venturi but I just can't get it to draw. Would bypassing the flow solve that problem? Seems counter intuitive that it would. Part of the reason the venturi I am using works so well is the awesome heads from rainbird. They spin almost 3 times as fast as the older style impact sprinklers but throw less water. I bought them for the freeze protection. Of course when I am freeze protecting I am not acidifiying the water and the venturi is bypassed anyway. http://www.rainbird.com/ag/products/...s/LFSeries.htm

[penandpike]

Wills,
Did you try the venturi with fully open hose without anyting restricting the water flow (like sprinklers) , maybe you just need bigger water consumer.If you did then I don't think it will work with the bypass. How the venturi works?I am sure you know that, but lets say it anyway:
When water enters the venturi it is in high pressure, then when it passes the narrowed part due to the increased speed the space between particles is bigger and so the pressure is lower.( lower then the outside atmosphere) After that the preassure is back to normal high level. So in order for the sucking to work we have to either increase the pressure at the venturi entry(For example - larger pump and bigger water consumer) or increase the pressure at the sucking entry (the solution you try to suck must be under pressure for example you put it in a agricultural sprayer and pump some pressure)
or we have to make the norrow space even more norrow so we can lower the pressure ( you can find the correct size pipe that will fit inside the norrow part and somehow stick it and make it stay there. It must have opening for the sucking ofcourse.) I don't know if this makes any sense especially my English!

[WillsC]

Pen,

I'm sure your English is better than my non existent Bulgarian Understood what you said perfectly.

With the larger venturi I don't think the garden hose would trigger it BUT I know the fill on my 300 gallon tote would as that is a straight 1.5" pipe with a valve. I wonder how many more heads would be required to make it draw.

Would the ag sprayer idea not be a problem because the amount of liquid being pushed in to the line by the sprayer would diminish as the pressure in the sprayer dropped?

[penandpike]

Wills,
Yes you are rigth for the sprayer( It is not very practical I just used it for example). Something more practical will be sticking something inside the narrow part. Like in the pic I drew.

[WillsC]

But doesn't that defeat the purpose as it would restrict it back to what I am using now? Think I will order a few more of the LF heads and try the 1" venturi again.

[penandpike]

Yes if you can use more heads will be the best. And you will irrigate faster.

[WillsC]

Well can never have too much freeze protection.......The back bed is lacking on the corners so think I will try adding 5 more heads and see what happens.....

[Darkman]

Yes try more heads and let us know. I can't understand why if you have enough heads that wouldn't work. It should be about total flow across the venturi and with the proper sized venturi you will get the necessary increase in velocity to create the vacuum on the discharge side.

[penandpike]

Wills,
You said that you don't acidify the water you use for freeze protection. then why you need the large venturi?

[WillsC]

Pen,

Well I already have the larger venturi and like you said it would be nice to get the fertigation done quicker AND more evenly. This winter I did add 5 new rows so the back bed is even wider and now the corners are getting some miss.

[penandpike]

Here I made two injectors working in parallel. One for sucking acid and the other for the fertilizers.

[WillsC]

Nice