Some interesting drip irrigation finding for palms

[Mauna Kea Cloudforest]

I wanted to pass along two really cool findings about drip irrigation as I am re-doing my entire system for my palms.

1) Most websites and irrigation tutorials suggest using higher flow rates for faster draining sandier soils. Some websites even show diagrams that have larger lateral dispersion for faster drip rates. But nothing could be further from the truth! Intuitively, the physics of capillary action suggest that the slower the rate, the more of a lateral distribution there is. I tried it out, and indeed, the lower rates provide a much higher lateral flow rate. I also found a good science research article that measured this more accurately and gor the same results.

https://www.academia.edu/494976/Wetting_Pattern_Simulation_of_Surface_and_Subsurface_Drip_Irrigation_Systems._II-_Model_Validation_and_Analyses

the whole pattern is being condensed in a smaller area when using a larger discharge emitter and using low flow rate emitter let the water pattern covers more area but with gradual decrease of moisture content.

It's obvious that 1/2 gallon emitters are a much better choice in sandy soil. In clay soil, there is more puddling with higher rates, so even there, a high rate is not desirable. But in sandy soil, there is an effect called "channeling" which causes too high of flow rates to create channels downward, not at all providing adequate wetting.

My conclusion is that it's better to have a 1/2 GPH emitter on sandy soil for twice as long than 1 GPH.

2) I have a lot of clogged drip irrigation parts, and buying new ones is expensive. I decided I'd give an ultrasound bath a try. For as little as $80, I was able to buy an ultrasound bath that leverages cavitation to clean drip parts. This Morning, i tried this on one of my old Orbit manifolds. I filled the ultrasound bath with acetic acid cleaner solution, and threw in one of my clogged manifolds. A 5 min treatment followed by a 10 minute soak and another 5 min treatment seemed to be enough to completely clean the manifold. A test revealed full flow restored to all ports.

I hope these results will be helpful to others who choose to leverage drip irrigation.

[Alicehunter2000]

Thanks Axel, although I don't currently use drip irrigation. ...it was an informative read.

[Gtlevine]

I use 1 gallon, 2 gallon and some 4 gallon J-Lock emmitters. 1/2 gallon emitters are too small for me as they will constantly clog up or freeze up. The constant heat in day then cool down at night causes enough expansion and contraction to somewhat warp the emitters and make them freeze. I have go through the yard every water cycle and twist them to get them working, its a pain in the ass. So i moved up to a minimum 1 gallon.

[Mauna Kea Cloudforest]

I use 1 gallon, 2 gallon and some 4 gallon J-Lock emmitters. 1/2 gallon emitters are too small for me as they will constantly clog up or freeze up. The constant heat in day then cool down at night causes enough expansion and contraction to somewhat warp the emitters and make them freeze. I have go through the yard every water cycle and twist them to get them working, its a pain in the ass. So i moved up to a minimum 1 gallon.

You have a filter on your system?

[Gtlevine]

I do have a filter.

[MattyB]

I don't see much of a difference in 1/2 gph versus 1gph. Even 2 gph is not "high rate". If you're getting channeling then the best way to solve that, and what you should be doing anyways, is to dig out the upslope side of the plant so that you have a mini-terrace. Then the emitters have a pretty level ground to spit onto. You can then allow mulch to cover the emitters and it often piles back into the mini terrace making it not really visible, but the hard native soil is still terraced and that'll eliminate any potential for run off. Really though, for densely planted hillsides full of a lot of plants that terracing might not be an option, but simply applying mulch will stop the channeling. Heck, you can get a hard downpour and you won't get channeling once your hillside is mulched.

[Phoenikakias]

Could you please explain how mulch stops channeling? Until now I knew thanks to Tom Blank that channeling is caused only by accumulated salts carried in the irrigation water and can be corrected with surfactant. I would expect if this is the only cause of channeling that compost may also help because of the humic acids, but mulch can be anything even lava rock or peebles and I can hardly imagin how such mulch washes off the residual salts.

[Mauna Kea Cloudforest]

I don't see much of a difference in 1/2 gph versus 1gph. Even 2 gph is not "high rate". If you're getting channeling then the best way to solve that, and what you should be doing anyways, is to dig out the upslope side of the plant so that you have a mini-terrace. Then the emitters have a pretty level ground to spit onto. You can then allow mulch to cover the emitters and it often piles back into the mini terrace making it not really visible, but the hard native soil is still terraced and that'll eliminate any potential for run off. Really though, for densely planted hillsides full of a lot of plants that terracing might not be an option, but simply applying mulch will stop the channeling. Heck, you can get a hard downpour and you won't get channeling once your hillside is mulched.

Yes, I agree with the swale approach. But I am not talking about surface channeling, I am talking about depth channeling. When you have a hillside that's effectively Swiss cheese thanks to moles (which I am trying to control, but it's easier said than done) and you have fast draining sandy soil, the biggest hazard of irrigation is water that basically goes straight down. My bubblers are 100% ineffective not because the water runs down hill, but because the water runs down the soil gaps. The higher the flow in sandy soil, the more likely the water will carve a path downward over time.

I've played with re-tilling the soil gently around palms to eliminate air gaps. In that case, the water pools more readily above ground. But the idea is to avoid all pooling and let the water seep into the ground so slowly that the water can wet the soil very efficiently and do so without mole holes interfering with the process. I can control the mole population, but getting a mole free garden is virtually impossible around here. So I have to expect that moles will come and tunnel.

[doubravsky]

I've also gone to 1 gph minimum or more often 2 gph emitters... with the exception of a few potted plants on hangers. With that I've had very few problems with clogging. I think during the last 2-3 years I've replaced maybe 4-5 emitters....

[Gtlevine]

Axel, your mole tunnels must be lined with resin, I never heard of such a thing. A 1gph emitter is like Chinese water torture, its not disappearing into the abyss.

[Tropicdoc]

Around here, we use this to fend off moles.

[Mauna Kea Cloudforest]

Axel, your mole tunnels must be lined with resin, I never heard of such a thing. A 1gph emitter is like Chinese water torture, its not disappearing into the abyss.

Gary, do you have a drainage system that gives you a measure of the amount of water that remains in the soil versus what drains downward? When I run my bubblers, all of it channels downward and ends up in my water tank. It trickles right through the hillside, down the french drains and back into my tank. I watched the 1 GPH flow, it's still pretty high. I need real Chinese water torture running for 3 hours at a time, now that's gonna saturate my soil.

[Gtlevine]

I dont know Alex, never seen your soil. But i water two hour increments with sandy DG soil and at the end you can see the wet spot in a nice diameter one foot all around the plant.

[MattyB]

You might try compacting clay soil around your palms/emitters to increase the horizontal capillary action. That's worked well for me in super "drainy" spots. Pooling is ok, that means it's not going down too fast. Plus once you mulch that'll soak up that pooling water and help spread it around as well.

[Mauna Kea Cloudforest]

Compacting soil really works for a while but a mole eventually comes around and tunnels under the drippers.

I've been experimenting with various types of drippers. Flow rates are all over the map and rarely as advertised. The orbit 1gph drippers put out a lot of water, some online purchased drippers barely put out any. Hard to find ones that work well.

[Gtlevine]

I use J-Locks Axel, they are very good. Also, i would not worry to much about where the water goes, the palm roots will find it regardless.

[Mauna Kea Cloudforest]

Gary, I will have to try those. I just tested the raindrip flag emitters, total garbage, seems like they have very poor quality control. They leak like crazy. Here's a photo of the Raindrip 1GPH dripper spraying stuff through the top at 15-25PSI. Raindrip stinks, terrible quality. See photo below.

The other bad product I bought are PC drippers from MrDrip.com, complete garbage as well. This is the product they sell, it seems like some sort of generic brand. About 30% of these drippers emitted almost nothing, and the others had flows all over the map.

It's been a nightmare to find good quality drippers.

Here's a photo of the raindrip 1GPH raindrip leaking emitter.

I know you don't believe in regulations, but this is an industry that I believe should be regulated. Customers are getting ripped off because the quality is low and the flow is anything but what is advertised. Who's gonna dismantle their system after installing a hundred rippers. I test them first because I don't want to install an inferior product.

[Stevetoad]

I use 1gph and 2gph DIG button emitters. I've yet to have a problem.

[Mauna Kea Cloudforest]

I use 1gph and 2gph DIG button emitters. I've yet to have a problem.

Steve, I am going to order some DIG through Home Depot. Raindrip has a distribution monopoly over Northern California, you can't find anything but Raindrip, and Raindrip truly sucks. it's the most horrible drip on the planet. It's what I installed 10 years ago and all of them clogged up.

I ran a test rig with a filter to test out the raindrip PC emitters. I used them for 10 hours on the garden, and they've already clogged. It's not my water, because I installed a 200 MESH filter. I will never buy another Raindrip product ever again.

I just hope that DIG is better quality.

[marinkeith]

taking this in a slightly different direction, but I am starting the process of completely replacing the drip in the yard. I have half inch supply lines running through the yard. In some places there are emitters - usually half gallon - directly in the supply line. In most, I have a short run of quarter inch line around the plants with inline half gallon emitters, and a half or full gallon emitter on the end.

I'm on a pretty steep slope in most places and except for some terracing with a lot of amended soil, its heavy clay.

My problems have been the usual - rodents gnaw through the quarter inch, the quarter inch gets hit by the weed whacker, the quarter inch gets stepped on and pops our of the supply line, sometimes the emitters in the supply line or quarter inch connectors pop on their own. I mulch a lot because of the clay which buries the emitters, causing uneven flow, increasing the number of times the lines get stepped on, pulled away from where they are supposed to be by animals. All of this means at the start of each watering season I need to walk the lines and double check/fix/reset everything, then constantly monitor for problems until the rains start. As you can tell, this drives me nuts (though my wife might say my nuts-ness has a variety of causes).

I was at the Cal Berkeley botanic garden this spring and saw a new section on their drip different than the usual set up. I checked they were happy with what they were doing and found they were using Netafim from Israel. The 17mm (essentially half inch) lines all have inline pressure compensating emitters which can operate equally well above or below ground so getting buried eventually is no issue. The line comes in emitters of .26, .4, .6, and .9 gallons per hour and 12 inch and 18 inch spacing between emitters. It also has a bending radius of 7" so it can be used to circle plants like I use quarter inch today without kinking. Their website gives recommendations on the emitter flow and spacing to use depending on slope and soil type.

The connectors are both easy to use and completely solid. I am hopeful that when the replacement is done, the amount of drip maintenance will drop to just new plantings. There will be no small pieces to pop loose, get eaten or nicked. And if it gets buried over time it won't matter. I have the better part of an acre to redo, so it will take me a couple months. But I will report back on how easy or hard it was, and whether the my dreams of being free of drip maintenance have been realized.

[MattyB]

Keith,

The Netafim product with the inline PC drippers is the bomb! Go for it, you'll love it. DIG makes a similar product but it's only 1 gph spaced 18" apart, so not as many customizable options as the Netafim, which is a commercial grade product. I use this product in my vegetable garden. Paul set up his entire garden with this product, because it's all densely planted, and it really serves his plants well.

This inline pc dripper product is great for areas with dense plantings and you want to saturate the whole area. Obviously it's a waste of water if you have long runs and lots of space between plants, in which case you'd want to stick with a solid polyline and add your emitters as needed.

BTW, I've found that even if you're on a slope, that if you're using your pressure regulators correctly, and not exceeding the recommended total gph, then the expensive PC (pressure compensating) drippers are a waste of money and regular drippers work fine. If you run 3/4" pvc (or 3/4" polyline if you can find it) as headers to different areas, then "pop-up" to your 1/2" polyline, then your volume will be greatly increased and you can run a shit load of drippers on one station without any pressure drop to worry about.

[Hammer]

Keith,

The Netafim product with the inline PC drippers is the bomb! Go for it, you'll love it. DIG makes a similar product but it's only 1 gph spaced 18" apart, so not as many customizable options as the Netafim, which is a commercial grade product. I use this product in my vegetable garden. Paul set up his entire garden with this product, because it's all densely planted, and it really serves his plants well.

This inline pc dripper product is great for areas with dense plantings and you want to saturate the whole area. Obviously it's a waste of water if you have long runs and lots of space between plants, in which case you'd want to stick with a solid polyline and add your emitters as needed.

BTW, I've found that even if you're on a slope, that if you're using your pressure regulators correctly, and not exceeding the recommended total gph, then the expensive PC (pressure compensating) drippers are a waste of money and regular drippers work fine. If you run 3/4" pvc (or 3/4" polyline if you can find it) as headers to different areas, then "pop-up" to your 1/2" polyline, then your volume will be greatly increased and you can run a shit load of drippers on one station without any pressure drop to worry about.

Jastin swears by the Netafim gear too. He's installed it all over his garden. I just installed it in one of my raised beds a couple of weeks ago. We'll see how it works out. I'm optimistic it will be a winner here. If so, I will be converting all my stations to Netafim.

[Mauna Kea Cloudforest]

Where do you guys get the Netafilm info? I've looked at their website, and I find the website impossible to navigate. Under what section is the tubing with inline pressure compensated drippers?

Edit: I did find these on their website: http://www.netafimusa.com/landscape/products/techline-ez, seems like the equivalent of 1/4" tubing. There is also a 1/2" tubing designed for reclamated water: http://www.netafimusa.com/landscape/products/techline-rw.

[marinkeith]

Netafim does make a variety of products, but the CV line is the bread and butter I described above. In the Bay Area, Urban Farmer carries Netafim but the selection of tubing options, at least at the Mill Valley store is limited. I've had to supplement local purchase with online. So far I've found that 1-800-irrigation.com is the cheapest, though they had to back order one thing I was looking for as well.

[Hilo Jason]

I use 1gph and 2gph DIG button emitters. I've yet to have a problem.

I'm with Steve on this. No problems at all with my DIG emitters.

[Mauna Kea Cloudforest]

I went to go return the Raindrip emitters at OSH today, the manager told me that they are getting 2-3 returns and complaints a week on Raindrip for leakage and clogging. They keep telling corporate to stop carrying Raindrip, but Corporate won't budge. Oh well, their loss. Raindrip sucks, the stuff is really poor quality.

[Perito]

I go to businesses that specialize in irrigation materials and parts. They don't even carry those inferior products and are able to give sound advice on various products and how to use them.

[Mauna Kea Cloudforest]

I go to businesses that specialize in irrigation materials and parts. They don't even carry those inferior products and are able to give sound advice on various products and how to use them.

If you know of such a business, I'd like to know who it is. Even the professional irrigation place here in Santa Cruz carries Raindrip, and they were utterly clueless. The guys at various online shops are utterly clueless as well, and the products they sell are also of poor quality.

[marinkeith]

If you can get to San Francisco, Urban Farmer is exactly the kind of place you are looking for. Its right near Darold's house.

[Perito]

My favorite is John Deere Landscapes in Arroyo Grande. They got into the Irrigation business several years ago and bought out United Greenmark.

They carry the various Neta-fim products as well as numerous types of emitters, filters, pressure regulators etc.

They have other stores in California.

[SHEP]

Axel, I buy alot of replacement parts from Ewing Irrigation, they have wholesale & retail. Netafim is well regarded and I have seen some commercial applications in wholesale plant supplies with over 12 acres. I do not know the cost, nor do I know if Ewing carries it.

Simplest way is to call Netafim, and asked to speak to their local rep, and he will tell you who carries they product. Cecile

[Mauna Kea Cloudforest]

If you can get to San Francisco, Urban Farmer is exactly the kind of place you are looking for. Its right near Darold's house.

I called Urban farming, the guy had no understanding of how Netafilm works. Pretty sad, really. I am coming up blank on finding a good, knowledgable Netafilm dealer. The local shops are utterly clueless as well, much worse even than Urban Farmer, like talking to meat heads that know how to dig a ditch but couldn't calculate a flow rate if their life depended on it.

[MattyB]

Hydroscape, John Deer, Ewing, these are the places down here. Where do your trade pros go? Shep has the right lead. Seek out your pro brands, contact them for local drealers.

[Mauna Kea Cloudforest]

I did, Matty. Pretty sad, most of the people are not very skilled. The local pro shop carries Raindrip only but can order other stuff. They have no understanding of the technical issues with a drip system.

I spent an hour reading the Netafilm drip product info, and I've already found a place to order all the Netafilm parts. I am converting my entire orchard and palm garden to Netafilm. I am tossing all my raindrip and most of my orbit out the window. After reading the Netafilm info, I can't see how anyone would bother with anything else. Here are the things I like about Netafilm:

1) guaranteed precise flow rates at 10-60PSI, very precise.

2) automatic shut off below 10PSI, so when you shut the system down, the water is still sitting there behind the emitters after shut down instead of dribbling out slowly and creating a vacuum that sucks in debris and bugs and cause fungus problems inside the irrigation lines.

3) flow control for pressure irregularities - around 5' column of water held behind.

4) self cleaning mechanism

5) No need for down regulating pressure - at 50-60PSI with enough emitters, pressure isn't 50PSI anymore anyway. You can go straight from a 1/2" PVC at 60PSI into the drip lines.

6) much cheaper than the Home Depot junk.

The precision part and anti-syphon is lost on most of the local shops I spoke to. They have no clue whatsoever that it matters. The other part is the ability to keep the drip underground. Conventional drip can't be put sub-surface because of the debris that get sucked into the system when the system shuts down.

Anyone who has any doubts on the intensity of the vacuum created in a drip system on a hillside can take a hose, set a drip rate by unscrewing a nozzle slightly, and run the hose down hill. After it shuts off, 2 hours later even the toughest hose completely flattens out, the capillary pressure of the drip water flow is very powerful. That is the primary reason why my drip system clogs up.

[Perito]

Axel there is a John Deere in Gilroy.

[monkeyranch]

I also use the 1gph emitter minimum as the 1/2 gph clog sooner.

I also agree Raindrip is garbage. The brittle plastic fittings wear out in the sun and crack if stepped on. Worse yet, they use their own diameter pipe (.620 OD vs. .700 OD standard) which does not mate with all of the other drip manufacturers parts, that use universal dimensions. And a final annoyance, they have exclusive shelf space at several hardware chains trapping customers into their hair-brained part specs. If your local shop only stocks Raindrip, I'd quickly find another shop.

For a good drip primer and price reference get a free print catalog sent to you from Dripworks.com. It's well organized and useful for getting a parts list together before a trip to the local irrigation store. Or order from them, they in Willits in Mendocino, prices are competitive, and delivery is fast. Ewing irrigation is a also decent choice but no parts bins to rummage through, just a desk where you present your list of parts.

I've worked in rugged vineyards in Mendocino and the Sierra foothills which can put irrigation parts to the test. Netafim take apart PC emitters are preferred by many and work fine. I've found the Toro TurboSC emitters even more durable. Pressure compensating and pop open very easily to clean the diaphragm of clogs.

I use 1/4" spaghetti tubing with emitters on the ends for nursery areas with 5 and 15 gallons. For landscape areas however, I like to stick with 1/2" emitter tubing with factory installed PC emitters or 1/2" tubing with PC emitters plugged in myself. The 1/4" and 1/8" spaghetti lines are too prone to problems. Deer, kids, gardeners, or other careless humans can easily trip over and pull apart the smaller lines. The straight barbs used to attach 1/4" tubing to the 1/2" mainline leak easily if moved around. They also clog easier and animals seem to like chewing on the skinnier lines. I don't have time to be checking for leaks and problems all the time.

And for the above wildlife reasons, I also use the grey plastic, barbed fittings with hose clamps rather than compression fittings. Even if they don't get pulled completely apart, the compression fittings sometimes develop a leak/drip/spray; as the plastic pipe ages it becomes less malleable and doesn't form as tight a seal with the compression style. I try to do everything heavy duty, assuming with enough use things tend to break.

I'd bet there is a good competitively priced, comprehensive irrigation store in Watsonville or Salinas area. In my immediate area the irrigation suppliers are unimpressive but 20 minutes down the road in Auburn is a great store called Sierra Anderson Pipe. I overlooked it for a while thinking it was a basic plumbing supply, but later discovered they had a great irrigation selection. Price savings more than make up for the short drive. Local family business too.

Good luck.

[monkeyranch]

Also these 1/4" barbs and fittings:

are more durable than these types: which snap easily.

Additionally, I find the DIG battery (and now solar option) timers hold up way better than Orbit (meh). For a quality multi-zone, whole property controller, Irritrol is one of the best.

[Perito]

You can use in line check valves to buffer the problem you are having on your steep runs down the hillside.