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Hello all, In a previous thread I stated that I was going to go with some sprinkler heads installed in series with pvc pipe to water the new garden but that was a bust because of my GPM which is too low to run them. I decided to go with my first plan which is a drip irrigation system. I am sure a lot of people use this method? I have one question is there a chart that tells how many gallons per hour certain veggies like? I want to match the emitters to the plants. Thanks all.

You actually don't so much match the emitters to the plants as to the soil type. The more organic matter it holds, the longer it will hold on to moisture. If you mulch it will slow evaporation from the surface. If your soil is sandy or drains really fast it will need watering more often.

When you choose emittters, calculate your total GPM and only use about 80% of the total amount. This needs to account for low pressure hours when you have a high demand for water in the house or even on your street. Add up the gph of the emitters and that will tell you how many total emitters you can have in a zone. For this I do have a timer and sprinkler manifold set up for 6 zones in my case. Only one zone can be watered at any time.
How long you water depends on how you place your emitters or microsprays and how long it takes to water the soil 4 inches deep. It does not take minutes, it usually takes hours.
Timing between watering does depend on location, time of year and plants. Group plants with the same likes together. Plants that like to dry out between watering in one place, plants in the shade or that need to be evenly moist together. Plants in full sun and exposed to wind or in containers will probably need to be watered every day. Plants in full shade with organic soil and mulch may be able to go longer between watering if you water deeply. Plants in summer will need to be watered more often and young plants that are properly spaced won't need as much water as larger plants.

Example of how mine is set up
zone 1 and 2 are turf zones with standard sprinkler heads 45 minutes each zone every 4 days. In the rainy season the sprinkler can be turned off. Grass is a water hog.
zone 3 is a border planting of roses, and under cover plants, alyssum, cuphea, lilies, glads, geraniums. 15 minutes every 4 days. non-compensating soakers. You can't find these anymore. Now most of the soakers are pressure compensated so they will drip slower than non-compensating. Time would have to be adjusted for how long it takes for the water to spread.
Zone 4 vegetable garden. Oval 8x15 ft One standard sprinker which I can change out to micro sprinker multi head if I need to. 15 minutes daily
zone 5 It has a tree that can live on rain but it was where I had my potted plants. It ran for 5 minutes every 4 days with one standard sprinkler head. I also hand watered.
zone 6 orchids on the trees. mostly 0.5 gph emitters and a Y to the front ferns and shrubs. I ended up adding one to many emiters and lost pressure, so I had to reduce the emitters until I could get flow to both areas. This was partly a problem of the water having to go against gravity up a tree. 5 minutes every day.
I had another faucet timer that with microsprinklers that went on for 5 minutes. I had problems with the ants getting in the timer and breaking it repeatedly so now I hand water it instead or I have to turn it on manually.

My timer has 6 zones up to four times a day and three programs. A, B, or A&B with battery backup
My water presssure is a miserable 37lbs and the board of water supply says it is my problem. I asked the neighbors if I could test their water. Within a couple of lbs we have the same pressure. The plumber said it was the water supply problem but they are not going to fix it. As a result, I run my sprinklers at night. Starting at around 2 a.m. when the pressure is the best and I and most of the neighbors are not using the water.

I did have more emitters and fewer standard sprinklers but the low water pressure meant that I had to run the system much longer into the hours when I also needed the water. Switching to fewer standard sprinklers and using microsprinklers worked better as I could deliver the water in less total time. The sprinklers are less efficient since it does get on the sidewalk but I lose less watering at night, than watering in the day when the water would evaporate. The plants have adapted to this watering pattern so I don't have issues with fungus except when it rains for days at a time.

If you have high flow emitters you can put out more water at any given time and you can space your emitters more. However, it limits the total number the line can handle. 0.5 and 1 gph drippers are usually the standard for single plants but it takes a while for those to get enough water. I still hand water to preload the soil with moisture. Large pots get 4gph emitters. My water pressure is so bad that I don't even use a pressure regulator. Most pressure regulators reduce pressure to 20 or 35 psi to keep the system from bursting. Emitters do clog and have to be changed out. The more salt you have in the water, the faster it clogs. You should check the sprinkler system monthly. Even standard sprinklers will clog and the heads get turned around and broken, so they have to be cleaned and replaced. My system is 26 years old and it is probably time for me to replace it.

Thanks for the info but I am still not clear on what I am going to need. I have sandy loam, well drained soil that I have ammended and want to continue to build and make better. I am only irrigating my 12x34 garden space as of now.

If you have added compost to the sandy loam it will hold water longer.
Are you going to run emmiters to individual plants or are you looking at microsprinklers
If you row plant you could also go with hydro tape or soakers.

It depends on the water demands of the plants and how fast your soil dries up.
12 x 34 is not a big area, but you may still want to zone it if your plants have different watering requirements or if the length of the system, depending on how you run it drops the pressure below 20 psi (which means some of your emitters won't be able to get flow.

In sandy soil the water will go down fast but the soil will also dry faster so you will probably have to water more often. Again you will have to do a test hole to determine how long it takes for the water to reach the 4 inch depth and how long it takes for it to dry up at that depth.
O.k. maybe these tutorials will help
https://www.mrdrip.com/Soaker-Hose-FAQ_ep_44-1.html
https://www.irrigationtutorials.com/dri ... -emitters/

I have been working with drip systems for over 25 years and this is what I learned
1. Emitters are compatible with most other similar systems but tubing and tubing connectors and "T"'s may be specific for one system.
2. To join two incompatible systems you need to have beginnings and ends.
3. Use an end cap with a cover. It will make it possible to connect an incompatible system to an existing one or connect a garden hose ( which I use as distribution tubing because it is cheaper). It also allows you to easily remove the cap when you have to flush the system. When you use the cheaper plugs and clamps, they come off much easier.
4. My system is on the surface so I can move it when I am working the garden and hopefully I can see it before I hit it
5. Get lots of goof plugs and connectors to do repairs.
6. Hydrotape is only good for one season and only useful if you plant in rows.
7. Do not mix emitters pressure compensating and non pressure compensating have to be on separate lines.
8. If you can water for 8-12 hours use pressure compensating. If you want to water over a shorter time non-pressure compensating is better but you have to be more careful how you adjust the flow and that you don't put too many emitters on a line.
9. If you cover the tubing with mulch (and you don't use a pick for a weeder), the tubing will last a little longer and won't get brittle as fast as when it is exposed to the sun
10 You will have emitters clog that have to be replaced. You will make holes in your tubes, you have to mend. But, for me that is easier to do than to have to cut and glue pvc pipe. PVC systems are rigid, but you can use pvc systems and connect drip to it if you are zoning different beds for instance.
11. Shorter tubing works better than longer ones. Less resistance
12 You can convert an existing sprinkler system to drip.
13 You can use a regular sprinker head on a riser "T" or use a microsprinkler on the same head with the right adapters.
14 water does not go uphill very well in a drip system and if the water is going higher than your anti syphon valve, all the time it will clog faster.
15 Use a water filter if you have hard water, the emitters will last longer.

It is not that hard but some of it will be seat of the pants kinda stuff like figuring out when you have reached the limit of the emitters you can place in line, how long to water (you do have to poke the soil for that), and selecting the right emitter, sprinkler or soaker that best fits your needs.
You can add up the gph of the emitters on a line or you can start on one end and work your way till you use them up. You can run a main line along the 12 ft side ( or whatever is closest to the source). You will run your rows off the main line. I have in line valves on each row of mine so I can turn individual sections off. You may be able to run two rows off one zone depending on the type of emitters or soakers you are using. You will need to run a mainline for each zone of your timer or if you do this manually you will have to turn each zone off and on yourself.
The other main advantage of having a timer and manifold is that you are usually connecting it to the water supply before it gets to the house. The street supply should be higher than any faucet you are getting water from after the house valve because the house valve reduces the street pressure to keep the pipes in your house from bursting. Normal street pressure should be 40-60 psi.
12 x 34 ft if you are planting in rows, a non compensating soaker will do if you want to water a short time. If you want to do an emitter to each plant, plan on watering longer.

If you use a pressure compensating soaker (which is the only kind I can find now), you have to plant according to the spacing on the line which is usually 12 or 18 inches and you will need to plant right next to the hole. You have to leave compensating soakers on longer.
I put in line shut off valves in my system so I can run one part of the garden while I work on another or if one part is not being used, I leave it off. When pressure is low, I sometimes have to run each section separately.

For increased versatility I use riser "T" I can use a standard overhead sprinkler when plants are small or short and change the head to a multi head (with individual shut offs) so I can run 6 lines from each head and use them like soakers or individual emitters for when tall plants would block the sprinklers.

If you mulch put the soakers under the mulch otherwise you have to water the mulch before any water hits the soil.

The other advantage is that when it comes time to harvest or till, since this is not a rigid system, you can move the lines out of the way.

I can't add much to what imafan26 posted! I can tell you a few things that I have learned through all of the years that I have been using drip irrigation.

I learned early on that non-pressure compensating emitters tended to clog; so frequently, in fact, that I stopped using them and tossed the 20 I started out with! They were easy to take apart, and clean out, but a wilted plant was the way I would discover that it needed cleaning. However, I don't really have a problem with the pressure, so the PC emitters work fine for me. Amazingly, if you have a low pressure, below the 15 psi usually listed as the minimum, a PC emitter can emit a solid stream, at a much higher output than listed!

I also use 1/2 gph emitters for almost everything. However, for something like some winter squash, in a row with smaller plants, with the 1/2 gph emitters, I use 2 gph emitters, since the plants are 4' apart, and need more water in the same amount of time. And for containers, I use some 1/4" drip line, in a circle around the plants, with a tee to connect to the main line, with a valve, to adjust the flow. I also have a lot of SIPs, which I refill the reservoirs in using drip emitters. Some plants, like tomatoes and cukes, really suck up the water once they get large, so I use higher output emitters in the same line with the peppers, which don't need as much, since they aren't as thirsty.

I have had good luck with getting more than one season out of T-tape/hydro tape, though I use the thicker grade - 15 mil. I have seen some as thin as 6 mil, so I can see how this would only last one season. I have gotten 4 seasons out of it, before a hole would appear, and maybe 1 or 2 more, cutting the tape where the hole was, and using a coupling. I use this in my garlic row, and my greens row, where things are very close together, and I use the high output (though it's really not nearly like 1/2 gph per emitter hole), and that with the holes closest - 8" apart. Running it about 2 1/2 hrs at a time runs the soaking areas together, and it is much better than a soaker hose, since at that slow rate there is very little runoff. I use this also in my herb beds, with one coming from a rain barrel, and the gravity is just enough pressure to water using this method.

Drip systems clog. I have to check them a couple of times a year. I did not have a lot of problems with the lazer drilled soakers but the recycled tire soakers were useless. I don't like the new pressure compensated soakers because the emitters are too far apart. I hand water as well everyday, but the sprinkler means I don't have to spend as much time doing it. I water what is not on sprinkler. I still find out there is a problem the same way you do, my grass was dying because I did not see that one of the heads was cracked so the rest of the grass was starving, but I did have 15 ft California grass growing in the broken sprinkler.

Its a good thing my grass is used to neglect, once it started raining it came back with a vengeance along with the weeds so I have to mow much more than I want to.

thanks for the replies. I am going to run emitters to my tomatoes, peppers and vining plants and soaker hoses to everything else.