Fertilizer injector + pesticide question

[BrassavolaStars]

Hello all,

I am preparing to do some pre-fall changes to my greenhouse "infrastructure". One of the things I had my eye on is a fertilizer injector like this

https://www.amazon.com/Fertilizer-In...379337&sr=8-11

I would like something that just adds the right amount of fertilizer to my hose water without me having to think about it much. I have had hose heads with mixing tanks before and did not like them too much because I found them to be fragile and cumbersome.

I had heard mixed things about injectors from my orchid club. That said, the Hoss one has really good reviews. Do they work well? Some people have told me they apportion fertilizer poorly if the pressure is not high enough. Is watering plants in higher places a problem then?

I would be hooking it up where my hose connects to the water.

Also, if I do get one of these fertilizer injectors, is it normal practice to put a small amount of Physan and fungicide and water with that every time?

Thank you.

[estación seca]

I have a Chemilizer plumbed into my outdoor irrigation system. I don't have to worry about the soil freezing.

Preventative treatment with antibiotics, fungicides or pesticides is a bad idea. It selects for chemical-resistant organisms to infect your plants.

[Ray]

BrassavolaStars, in my opinion, you want to stay away from that kind of injector.

The problem with siphon-type injectors is that they require substantial pressure and flow to work properly, so household water pressure and hoses can play hell with them.

Your pictured injector, however, is not a siphon type at all, even if the hose attachment looks similar. With that and similar devices, such as EZ Flow, one hose directs water into the tank, and the concentrate in the tank is thereby push out of the tank and into the hose, where it is mixed with the water.

The problem with them is that the concentration of the fertilizer delivered to to plants changes, becoming more and more dilute over time, as the injected water dilutes the concentrate in the tank.

So, if you want to apply a 100 ppm N solution to your plants, you’ll have to mix the concentrate tank to deliver 200 ppm N at first, realizing that over time, the delivered solution will diminish to zero fertilizer.

The sellers claim that the liquid in the tank remains stratified, so the concentration delivered stays quite stable until it nears the end, but I am unsure how reliable that is.

A metering pump like the Chemilizer ES mentioned is a better option, if twice the price. There are Chinese-made knock-offs available on Amazon for about the same money as your Hoss option. I have had customers tell me they’re pleased with them.

As to the pesticide part, adding bleach or Physan is intended to keep the bacteria colony that will form over time at bay. I tried Physan for a while, but the amount of protection it offers is minimal, unless you use a lot, and I don’t think that’s a great idea. There are two ways to slow or prevent the issue from occurring:

the tendency is to make a strong concentrate so you needn’t refill the tank often, but if you’re willing to refill it more frequently, there won’t be time for the mat of bacteria to grow.

Second is to devise a “liquid lock”, like that used on a fermenting tank, filling it with bleach or Physan instead of water. As the liquid is drawn out of the concentrate tank, the air entering the tank bubbles through the disinfectant, minimizing the passing of live, airborne microbes.

[BrassavolaStars]

Hello all,

Thank you for your replies. Here is a look at what I am working with in terms of my water infrastructure. The pipe coming out of the house is maybe 3 inches long at best and barely comes out past the stone (the plus side is it’s too close to the house to freeze). That pipe goes to the detachable splitter and the hoses. I wanted something that could ideally attach between the splitter and the hose. I’m willing to spend up to a few hundred, but I cannot alter the plumbing coming from the house. Getting a plumber is definitely a hard “no”. What are my options?