fertigation w/ drip systems

[MattyB]

Anyone with any experience introducing water soluable fertilizer into their drip/micro irrigation systems via the filter? What fertilizer do you use? How do you get it in there? Do you fill the filter or use a tea bag sorta method? I've read about slow dissolving tablets, where can you get these? Please share if you've got any ideas or info. Thanks,

Matt

[elHoagie]

Matt - everything at my place is drip, and I'm using water soluble fertilizer. Originally I was using "Grow More Palm Formula". But, I can't find it close by anymore, so now I'm using "Grow More Rose Formula", which isn't much different.

I've never tried putting it in at the filter. I have a cheapo main-line injector from EZ-Flo, which has worked well...

[doubravsky]

I have the EZ-flo as well.... and I like it a lot. I use peter's 15-5-15 cal mag formula.... which has gotten FREAKIN expensive.... ($50 for 25 lbs). Hoagie... how much does yours cost you?

[MattyB]

Hmmmmm, I like that idea but putting one unit on my main line, that runs down the hill and serves the yard, seems like it would create problems for when I just want clean water to come out of my hoses, ie. dog water and stuff like that.

[Paul The Palm Doctor!]

Matty, that's what I was concerned with, especially in our hard water areas. How do you two guys manage the successful separation of the clean vs. nutrient water? Dual valve coupler? Or does the switch occur automatically when feeding with a tumbler locking set up?

El Hoagie: what's the water output per plant per minute; just curious? Does it underwater on windy days, on desert day days?

(If I wasn't so damned lazy, I would look at the online catalog, er, I guess Matty would, too?) I'm slipping, guys; it's embarrassing!

"Must be the end of the road for..." Paul

[Justin]

I have a tank just before the inlet to all my valves. It's on the mainline, but AFTER the backflow preventer. In retrospect I would have set it up differently. What I would have done is set up a parallel line just before the fertigation tank. On each of the two parallel lines I would have a ball valve. That way, if I wanted to use fertigation, I would close one valve and open the other. If I wanted no fertigation, I would close the opposite. It would also make filling the tank much easier, as you could ensure there was no water pressure on the tank line when filling it.

[MattyB]

I hear ya Justin. See, my irrigation valves will occur at different spots all along my main which runs down the property line.

[doubravsky]

I have a main line that feeds the lawn and the pool filler valve, so I couldn't go with the main line unit. I used the Ez-flo 1 1/3 gallon tank that attaches right after the valve. So I ended up with 4 tanks at the four different valves that hit the planters front and back. At $65 a piece it ended up costing about the same as the main unit.

It's a little more of a pain because I have to fill 4 tanks with fert. once every few weeks.... but it's not too bad. Each tank holds 8 lbs of fert.... and for my lines that will last 2-3 weeks now, maybe 1-2 weeks during the heat of the summer when I'm watering a lot.

If I had it to do over again I'd have dual main lines... one for fert, one for clean water. Too late for that now....

[freakypalmguy]

I am looking to do this as well. Here is Kevin Weavers setup. He uses the ball valves like Justin mentioned to decide when he will fertilize.

[LJG]

I am still sitting on a Dosatron in its box after almost two years. This is exactly how I wanted mine set up. However after thinking about it, I have kids, dogs, etc and 450 pop-ups. Plus a few hose bibs. These long runs to clear the fert from the hose lines was going to be an issue. I was going to just use organics, but even those have build up.

Looks like I ill just use the Dosatron for the greenhouse.

  freakypalmguy said:

I am looking to do this as well. Here is Kevin Weavers setup. He uses the ball valves like Justin mentioned to decide when he will fertilize.

[MattyB]

I'm thinking maybe a small unit per each station so that the clean water vs fertilizer water won't be an issue. Like Dave did. Looking at EZ-flo's website it looks like I can even thread and tap 1/4" lines into the exising 3/4" PVC line so I don't have to cut and glue a fitting in.

[sonoranfans]

If I had sandy soil this would make more sense for me, as sandy soil is hard to keep nutrients up to a consistent level. In the desert during the hottest part of the year, salts will be deposited near the drippers on the granite rock, not good. Also, because I use humic acid/w kelp frequently, this is not viable delivery system as it clogs the drippers, and the sediment would not be delivered as effectively to the perifery of the irrigation system(sediment will be delivered more heavily in close to the delivery tank. Another issue is that if you develop a below ground leak, you end up fertilizing that area as much or more than a palm. However, if I had to run up and down a big hill to fertilize, like matty, I'd seriously consider an in line system With my scenario, I spend a half hour every 3-4 weeks fertilizing, and it gives me a chance to look thinks over and put extra down on some and less on other palms. No sense in giving alot of Mn, MG, Fe to a brahea armata or bizzie anyway, they just dont need as much as some other palms. I guess I am old school, I like to hand wax my car as well.

Edited March 24, 2009 by sonoranfans

[elHoagie]

Dave - I don't remember what I paid last time for the fert, but I think about $25 or $30 per 25 pound bag...

Paul - I use 2 gallon per hour drippers for most of my palms. The weather in the summer here never changes (no wind, no rain), so I never have to adjust the water schedule (either once or twice per week depending on the plants). In the winter I just set the schedule by hand based on what the weather is.

Justin - My setup is similar, the main line injector is after all the house water and hose bibs with a backflow protection in between. I'm so glad I put a shutoff valve before the injector, that must be a pain in the ass to add fert to yours...

Matt - I have one of those downstream EZ-FLOs in the front yard because I couldn't connect that zone to the main line injector. I initially purchased those threaded bibs to connect to the 3/4 PVC, and it did not work at all. Maybe I just did something wrong with the threaded bibs, but I ended up purchasing one of the PVC couplers with bibs from EZ-FLO - everything works great using that coupler.

[elHoagie]

Also, shop around for a while before purchasing the EZ-FLO units, there was a HUGE difference in price from one website to another.

[Mark Heath]

Interesting information! I have purchased my materials for in-line fertilization at my palm grove but i have'nt installed it yet. I plan on using a Venturi system. A Venturi works where it will suck from a tank filled w/ fertilizer while the water is flowing and will stop when the pump/pressure stops, no electric required for the Venturi pipe. The Venturi pipe has a restricted

part to it and that causes suction. I also plan on doing the double ball valve as well when i don't want to water w/ fert.

Be sure and use scrubber valves when running fertilizer through them. If you have regular valves they will corrode and falter in time.

There is no need to purchace a pump, it is alot more expensive and the Venturi does just as good of a job.

I have a 30 gallon tank that i will have filled w/ liquid fert and when that sucker goes dry, i'll go get another one,

The price quoted for me was $150.00 for 30 gallons.

Matty, if you hook up your system just like the pic that Matt posted you will not have to worry about fertilizer when you don't want it. BUT,,,, you would have to manually shut off your fertilizer injector before you close your ball vaves.

If you go w/ Venturi, you will have automatic clean water when the fertilizer tank runs out of fertilizer. Also, if you want to fill your pool or anything else you can close the ball valves and bingo, you have clean water after everything is flushed out of course.

You can also run Subdue or any other fungicides through it (recomended)! Also you should run diluted bleach once a year to clean the scum from inside the lines. I worked at a nursery for a few years when i was younger and i took care of the irrigation system. I had allways dreamed of having my own nursery.

I have a 2inch pipe that runs 35lbs of pressure and each bubbler produces 8 gallons per hour. I have only 3 valves at the moment but each valve supplies water to 700 palms.

Dave has a good point about dual lines, i have no isues w/ that because at the palm grove the deep well is there to only supply the palms w/ water and soon fertilizer!

I have a shallow well for the trailer.

I wish i had everything installed so i could take pics!

[Tassie_Troy1971]

If i had your huge area Matt i would be doing everything possible to make life easier and fertigation sounds ideal .

I have a dripper on every palm, 2 on the bigger ones so hmm!!!

[Paul The Palm Doctor!]

  elHoagie said:

Dave - I don't remember what I paid last time for the fert, but I think about $25 or $30 per 25 pound bag...

Paul - I use 2 gallon per hour drippers for most of my palms. The weather in the summer here never changes (no wind, no rain), so I never have to adjust the water schedule (either once or twice per week depending on the plants). In the winter I just set the schedule by hand based on what the weather is.

Justin - My setup is similar, the main line injector is after all the house water and hose bibs with a backflow protection in between. I'm so glad I put a shutoff valve before the injector, that must be a pain in the ass to add fert to yours...

Matt - I have one of those downstream EZ-FLOs in the front yard because I couldn't connect that zone to the main line injector. I initially purchased those threaded bibs to connect to the 3/4 PVC, and it did not work at all. Maybe I just did something wrong with the threaded bibs, but I ended up purchasing one of the PVC couplers with bibs from EZ-FLO - everything works great using that coupler.

Thanks, Jack for being patient and taking the time to respond so well to all of our "issues"! (I think that maybe I owe YOU the

beer on my next western pilgrimage!) This is wonderful information that gains more precedence & importance as nationally (especially far SE to far SW USA) water resources just aren't going to become more abundant, and water "wars" are engaging many reservoir-dependant states (and which staes aren't anymore?) You guys have lived with limited (AND monitored/meterd consumption of water) as an everyday "natural" way of life.

Floridians (& Southeasterners, in general) were/are spoiled as our rainbirds just throw water out of their valves (like beads are thrown at people during New Orleans' Mardi Gras) in way too unnrcessary quantities; that's why I have outrageous $300.00 + water bills every month. I need to get smart here in So. Fla., if I know I have better things to do with my $300.00 X 12 than to heap it way too lavishly onto my irrigated natural "rain forest" garden. (a rate of 2 gal/hr. for palms IS plenty.) I don't even know how much I exceed that by; I had better KNOW what the heck I'm laying down...and soon!

You all have taught me so much, with this particular discussion, that I could have never learned otherwise! Thanks Doubravsky, Justin, El Hoagie (& MattyB. for asking the initial question!) You guys rock!

Late.

Paul

[Mark Heath]

Paul,

2 gallons per hour is plenty if you have soil that will hold the water. At my home i water once a week for an hour, and that is only the potted palms,, i dont water the palms that are rooted into the ground, it's not neccasary w/ the good soil that i have here and we get enough rainfall.

At the palm grove i have sugar sand w/ zero soil and if i reduced it

to 2 gallons per hour my palms would dry up! I water twice a week an hour a zone. The palm grove is on the Lake Wales ridge and looks like a desert! Most people would'nt have this problem that i do.

Also, Matty had asked about fertigation, and using the Venturi system means you only have to buy it once and you do not have to buy an injector which will eventually break down and you'll have to buy another one.

Matty, please use scrubber valves if you allready have'nt installed regular ones, they last 10 times longer and are designed for a fertigation system.

My suggestion is to sink a shallow well so you don't get big water bills w/ using city water, and the well pump will be the only electrical component so electric bills will be small. The valve control panel uses low voltage.

You will also be able to seperate clean water from fertilized water easily. That question had been asked as well.

I have installed many irrigation systems in the past and present and when it came time for me, this is what i did.

[freakypalmguy]

Mark,

I like the non moving part aspect of the venturi system. This system seems like an inexpensive way to go.

Here is a link to dripworksusa

Here is a direct link to the manufacturer Mazzei Fertilizer Injectors

[sonoranfans]

  Tassie_Troy1971 said:

If i had your huge area Matt i would be doing everything possible to make life easier and fertigation sounds ideal .

I have a dripper on every palm, 2 on the bigger ones so hmm!!!

The most common mistake about drip systems is not using enough drippers or not using a flow rate that is matched to your soil drainage. In my clay based soil I use not less than (3) 2 gallon drippers per palm, with up to 6 on the bigger palms like a large bismarckia. One dripper is good for a small plant, but will not wet a very large root zone, and will lead to poor root development.

Here is an article:

http://www.ext.colostate.edu/PUBS/Garden/04702.html

here are some key discussion points

Disadvantages

If emitters are poorly placed, too far apart or too few in number, root development may be restricted by the limited soil area wetted. Water seeping at ground level is hard to see and makes it difficult to know if the system is working properly. An indicator device that raises and lowers a flag to show when water is flowing is available to overcome this issue.

Regular maintenance inspections are needed to maintain system effectiveness—the same as with high pressure sprinkler systems. Clogs are much less likely with filtered water and proper pressure regulation used in combination with self-cleaning emitters.

Where to Drip: Placing Emitters

Drip irrigation emitters must be placed so that water reaches the roots of plants. Roots will grow where conditions are favorable, primarily where there is the right balance of water and air in the soil.

Design the drip system around the irrigation needs of the plant. For new plantings, make sure emitters are placed over the root ball. Initial placement on perennials is often permanent unlike trees and shrubs that require emitters to be moved away from the trunk and others added as plants grow. Generally, larger plants have larger and more extensive root systems. A greater number of emitters is needed with larger plants and higher water-using plants. Fewer emitters of lower flow are needed with lower water-using plants or plants that will receive only occasional water following establishment.

In clay or loam soils, consider two 0.5 gph emitters at the base of a perennial flower to ensure watering if one fails. A 1 to 5 foot shrub and small tree less than 15 feet at maturity will initially require two, 1 gph emitters 12 inches from the base of the plant. Change to 2 and then 4 gph higher flow emitters if planting a larger sized tree and as the small tree grows. A 5 foot or larger shrub may require three 1gph emitters.

A medium tree 15 to 25 feet may ultimately require four emitters two feet from the trunk. If planting a “whip”, it’s possible to start with two 0.5 gph emitters and change to higher flow and more emitters as the tree grows. Begin with three, 2 gph emitters on a 1 inch caliper tree planting and three, 4 gph emitters on a 2 inch caliper tree at planting.

Trees larger than 25 feet at maturity may be impractical to irrigate with drip because of the extensive nature of tree root systems and mass of the trees. Increase the number of emitters and change them to 2 or 4 gph or larger flows as trees and shrubs grow.

Drip emitter placement is also related to whether the soil is sand or clay. To compensate for variations in lateral movement of water in the soil, locate emitters 12 inches apart in sand, 18 inches apart in loam, and 24 inches apart in clay. If one to two emitters are recommended for a plant in a clay soil, two or three may be required in a sandy soil to wet a sufficiently wide soil area. This statement is a bit simplistic, but its a good start in understanding th enature of drip irrigation. I deally the emitters should be placed at the tree drip line to best effect growth/health.

This is a beginners article, there is more regarding the design of drip systems and placement. In clay soils, lower volume drip emitters are used(2gallon/hr max), in higher drainage or sandy soils, higher volume emmitters or microsprinklers are better.

some points:

1) when using drip irrigation on a slope use lower flow emitters with more on the high side of the plant, or dig a trench to trap the runoff. This is expecially needed for clay soils on sloped ground.

2) as the plant grows move emitters away from the trunk towards the drip line and add some extra emitters.

3) Water for longer duration in clay soils, up to 9 hours in length. The longer watering duration with low rate emitters can make up for the use of fewer emitters. in low drainage soils

4) if you plant palms in groups, they can share emitters and reduce the number required for good root development.

5) you can also plant the palm in a depression in clay based soils and water longer (flooding the basin) to distribute the water more uniformily. This basically traps the water in the root zone and permits a more even deep penetration zone.

Since most arizona residents depend on drip irrigation(8" rain a year), the city govt offers free training in its use. If they arent used properly here, many trees, especially most palms, will look like crap.

Edited March 25, 2009 by sonoranfans

[elHoagie]

Thanks for the information Tom. I've been thinking about the issue myself, because I'm limited to approximately one emitter per palm due to the number of palms I've planted per zone and the maximum flow rate of the main line. In any case, I don't think this will be a problem because I've planted things so close together. Basically, each palm only has one emitter, but there are several emitters within a couple meters of the palm because there are several other palms within that area.

I've also planned ahead in case my original thought doesn't work. All of my zones are set up so that they can easily be split into two separate zones, which means I could double the number of emitters in each zone.

[MattyB]

Thanks for the good info. I'm contemplating what rate emitters to use too. Also, the spacing thing is a lot to think about.

[sonoranfans]

  elHoagie said:

Thanks for the information Tom. I've been thinking about the issue myself, because I'm limited to approximately one emitter per palm due to the number of palms I've planted per zone and the maximum flow rate of the main line. In any case, I don't think this will be a problem because I've planted things so close together. Basically, each palm only has one emitter, but there are several emitters within a couple meters of the palm because there are several other palms within that area.

I've also planned ahead in case my original thought doesn't work. All of my zones are set up so that they can easily be split into two separate zones, which means I could double the number of emitters in each zone.

Yep Jack,

Planting palms/trees/plants close together is a winner with drip irrigation. In my high pressure city water application, the size of the valves and pressure rating determines the capacity. I have about 50 palms( >100 emitters) on one zone with my 60PSI 1" valve. Grouping the palms together allows me to keep them much happier with less water. My other zones I use for the less water demanding trees and palms(e.g. braheas) and the timer is set for a lower irrigation frequency at that station. Drip irrigation is an invaluable tool for those of us that want to grow things but conserve water. If socal folks go to drip irrigation in mass, water usage will be less and watering more effective. One caveat is that high drainage(sandy) soils are not a good match for drip irrigation. Irrigation in those soils is better addressed with micro sprinklers, or by ammending the soil with clay to prevent rapid drainage. Clay soils are very efficient when it comes to water use. When I was ignorant I cursed the clay as it was hard to dig, now it looks like a very good thing as long as the soil pH isnt too high.

MattyB: your application is a challenging one for sure with the elevation change and length of irrigation pipe. But since you irrigate downhill, your flow volumes will be better, you sound like you've thought it out well. On the slopes, I'd try to dig or otherwise create some catch basins in the palm root zones to limit runoff and help with deeper irrigation. I, like many here, am very interested in seeing pics of your place in the years to come, should be a fantastic palm garden.

[MattyB]

My flow volumes should be ok since I've ran my headers entirely as 3/4" PVC with stub outs periodically where I can begin multiple 1/2" poly runs. Also, I've placed my valves at or above the zone it's watering. I'm most torn on what to do in my rainforest area. Palms/trees are planted very densley here. I already have catch basins because I water by hand now. Heavy ammendments in the backfill make for a great bucket effect when watering by hand. I plan on encorporating micro-sprayers in this area too, to keep the mulch and the entire surface moist in this area. Considering I'm spraying too, I'm torn between (2) 2 gallon emitters per plant and watering for 1 hour or (2) 1 gallon emitters per plant and watering for 2 hours, or (1) 2 gallon emitter per plant and watering for 3 hours. I just don't konw. Also, my soil, although having good clay content, is shallow and basically hard pans out to rock at 12"-18" deep. The locals say that watering frequently at short intervals has worked best for them. But with drip I don't know how that will translate.

[sonoranfans]

  MattyB said:

I'm most torn on what to do in my rainforest area. Palms/trees are planted very densley here. I already have catch basins because I water by hand now. Heavy ammendments in the backfill make for a great bucket effect when watering by hand. I plan on encorporating micro-sprayers in this area too, to keep the mulch and the entire surface moist in this area. Considering I'm spraying too, I'm torn between (2) 2 gallon emitters per plant and watering for 1 hour or (2) 1 gallon emitters per plant and watering for 2 hours, or (1) 2 gallon emitter per plant and watering for 3 hours. I just don't konw. Also, my soil, although having good clay content, is shallow and basically hard pans out to rock at 12"-18" deep. The locals say that watering frequently at short intervals has worked best for them. But with drip I don't know how that will translate.

With rock underneath sounds like a reason to water shorter duration as your locals have apparently found. I would water the tropical zone more frequently for shorter duration(with th eunderlying rock). I would also use the smaller emitters doubled up as the irrigation will be more even, promoting better root development. I might also ammend the upper soil with vermiculite, it traps water really well, and doesnt decompose in time like compost. A 3 cu ft bag costs about $20 at home depot. I have a bangalow that is doing well in this desert, in part, because of the 3 gallon volume of vermiculite I added to the root zone. Vermiculite, clay and some sand has some real staying power in retaining moisture. Its always damp, and I water it with my plant line(most frequent schedule).

One issue that I have found with smaller( 1 gal, 0.5 gal) emitters is that they tend to clog easier due to water (hardness) deposits, and that will just be more of a problem with fertigation.

Edited March 25, 2009 by sonoranfans

[Mark Heath]

  freakypalmguy said:

Mark,

I like the non moving part aspect of the venturi system. This system seems like an inexpensive way to go.

Here is a link to dripworksusa

Here is a direct link to the manufacturer Mazzei Fertilizer Injectors

That's what i'm talking about!!! Good job Matt w/ posting the links! That venturi pipe will out last 3-4 electric injectors!!

That is exactly what i have ready to install at the palm grove. I have'nt gotten around to installing because i can't afford the liquid fertilizer untill i get my tax return back!!

[palman]

I am slowly converting most of my sprayers into drip systems. Here in Florida we need to shift away from broadcast spraying water onto our lawns to maintain thirsty St. Augustine turf and use less thirsty groundcovers instead with drip irrigation to deliver water to specimens among the groundcover.

THANKS for the info here!