Advantages & Benefits of Drip Irrigation

 

In this time of water and resource conservation, drip irrigation makes sense. It is generally less expensive to install than conventional subsurface PVC systems and uses much less water.  

Water Conservation - Drip irrigation allows you an efficient watering by supplying water where it is needed - at the very roots of the plants. As a result, water is not wasted on leaves or soil. This significantly reduces the chances for evaporation and run off. Both are common with traditional irrigation systems where the water is often supplied at a rate greater than the soil can absorb it.

Reduce Weed Growth - When water is applied using a conventional sprinkler, everything gets wet. Since drip irrigation applies water to the root zone of your plants, the spaces in between plants remain dry. This greatly inhibits weed seed germination. If the soil remains dry, most seeds will not germinate. Landscape maintenance takes less time with drip irrigation.

Reduce Plant Stress - When plants get deep, consistent watering, they thrive. Inefficient, shallow watering can contribute to plant stress. Promote healthy growth and disease resistance plants in your garden with drip.

Extremely Flexible Application - You have many options with drip irrigation tubing, fittings, and emitters. It is a versatile watering system which can easily be installed on hillsides or flat terrains. Drip is the perfect irrigation method for oddly shaped landscapes and windy areas. Existing sprinkler systems can be retrofit with drip irrigation with very little effort.

Save Money - Once a drip irrigation system is installed, you will use less water to irrigate. If you are on a well, you will notice a severe drop in your pumping costs. You will no longer need to hand watering your garden. Automate you system with an irrigation controller and eliminate the need to pay someone to while are on vacation. With the reduction of plant disease and unwanted weeds, your gardening labor and maintenance costs will also drop considerably.

 

 

Installing Drip Tubing & Fittings

 

1/2" Solid Drip Tubing (main line) & Compression Fittings

The most common size of main line drip tubing is "700" - .700" O.D. (Outer Diameter) x .600" I.D. (Inner Diameter). It is often called simply "1/2 inch drip tubing". That said, not all 1/2" tubing is the same size. Confused? Read more about drip tubing sizes in our tutorial called "What size is my drip tubing?". This is the main feeder line for your drip irrigation system. It is used to create manifolds and branch lines. The maximum distance that you can run drip tubing will vary with the number of emitters you install and the spacing between emitters, but here are two conservative guidelines:

 

Maximum Run per circuit: 200 ft

Maximum Flow Capacity: 220 gph

 

Our  Drip Tubing Maximum Run Chart (PDF) will help you compare different scenarios. The maximum run will increase if you use low-output emitters (1/2 gallon-per-hour). Increasing pressure regulator size from a 20 psi regulator to a 30 psi regulator will also extend the distance that you can run drip main line. 

 

We carry the following sizes of  700 drip tubing:

 

1/2" Drip Tubing (700) 100 ft

1/2" Drip Tubing (700) 500 ft

 

Install drip tubing with compression fittings. The tubing is inserted into the fitting and requires no glue.

 

Use clippers to cut 1/2" tubing.

 

 

 

 

 

 

 

Installing a compression elbow

 

 

 

 

 

 

 

 

Installing a compression tee

 

 

 

 

 

 

 

 

 

Installing a compression coupler

 

Installing a compression end cap (threaded)

 

 

 

 

 

 

 

Drip main line tubing with compression coupler and threaded end cap

 

Installing a figure 8 end plug

 

 

Installing a goof plug. Also, called a "mistake plug", it is great for plugging small holes in drip mainline tubing. If you need to move an emitter or a 1/4" barbed fitting, just pull it out and replace it with a goof plug.

 

A 1/2" Flow Control Valve allows you to reduce the flow to a drip main line shut it off completely.

 

 

 

Connecting different sizes of drip tubing.

Use adapter compression fittings to join drip mainline tubing of different sizes. Note that colored compression rings correspond to tubing size. For more information on tubing sizes,  read "What size is my drip tubing?".

700 (black rings) x 710 (blue rings) - DD-CCA700-710

 

700 (black rings) x 620 Raindrip (green rings) - DD-CCA700-620

700 (black rings) x 580 (yellow rings) - DD-CCA700-580

700 (black rings) x 455 (red rings) - DD-CCA700-455

 

Build your own compression fittings

You can easily convert a 1/2" slip PVC fitting to a compression fitting.

Apply PVC glue to 1/2" slip fitting

Apply glue to compression ring

Insert compression ring into PVC fitting

Finished compression ring installation

 

 

1/4" Drip Micro Tubing & Barbed Fittings

 

Also called "distribution tubing" or "spaghetti tubing", the most common size is .250" O.D. (Outer Diameter) x .170" I.D. (Inner Diameter) .  It is available in Polyethylene (PE) "Poly" or Poly Vinyl Chloride (PVC) "Vinyl". 1/4" Vinyl Tubing is heavier than 1/4" Poly Tubing. Vinyl tubing more flexible and easier to work with, but is also more expensive. 

 

This tubing is most often used to branch off from main line drip tubing to individual plants. Drip emitters are attached to the ends of 1/4" drip tubing and staked next to plants. Check out this tutorial to learn about choosing the best drip emitter.

 

1/4" drip tubing does not have the same water carrying capacity as 1/2" drip tubing. Keep the following restrictions in mind when using 1/4" micro tubing:

 

Maximum Run per branch: 50 ft

Maximum Flow Rate: 30 gph

 

We carry the following sizes of  1/4" drip tubing:

 

1/4" Drip Tubing (250) Poly - 100 ft

1/4" Drip Tubing (250) Poly - 1000 ft

1/4" Drip Tubing (250) Vinyl - 100 ft

1/4" Drip Tubing (250) Vinyl - 1000 ft

 

Install 1/4" drip tubing with barbed fittings. The barbs are is inserted into the tubing and require no glue.

 

Use scissors to cut 1/4" solid micro tubing.

 

 

 

 

 

 

 

 

Our Deluxe Hole Punch cuts a clean hole in main line drip tubing. 1/4" barbed fittings are inserted into the hole.

Inserting barbed coupling  into main line          Barbed coupling with micro tubing

 

Barbed coupling attached to 1/4" micro tubing

Attaching 1/4" tubing to 1/4" barbed tee                            1/4" tubing attached to barbed tee                                                  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Inserting barbed tee into main line tubing               Barbed tee attached to 1/2" main line

 

 

 

 

 

 

 

 

 

 

 

Inserting barbed elbow into 1/4" micro tubing

 

 

 

 

 

 

 

Inserting barbed elbow into drip main line

 

 

 

A barbed cross connects 4 lengths of 1/4" drip tubing

To cap off 1/4" micro tubing, install a goof plug.

A bug plug will keep insects from crawling into 1/4" drip tubing while water flows freely.

A 1/4" Flow Control Valve allows you to reduce the flow to a drip line shut it off completely.

 

 

 

 

 

 

The 1/4" Flow Control Valve can also be attached directly to drip mainline tubing .

 

 

Choosing the Right Drip Emitter

 

There are Four things to consider...

 

1. Pressure-Compensating vs. Non-Pressure-Compensating Emitters

First determine whether or not you need pressure-compensating emitters. They cost a little more but are the best choice for many applications. If your landscape has elevation changes (hills, dips, etc.) go with pressure-compensating emitters. They have a diaphragm inside which maintains the same water flow through the emitter even if the elevation (and pressure) changes.

 

The PCE Series is our best quality pressure compensating emitter.

 

     1/2 gph (gallon per hour) best for Clay Soils (hard)
     1 gph best for Loam Soils (normal)
     2 gph best for Sandy Soils (loose)
     Self-flushing
     Inlet pressure can vary from 14.58 - 58 psi

 

 

 

 

Rigid Riser Extensions can be used to increase the height of  Micro Stake Assemblies. They are available in lengths of 8", 12", and 18".

    8" Rigid Riser Extension  
   12" Rigid Riser Extension
   18" Rigid Riser Extension
    Riser threads into the top of stake

 

 

 

 

Micro Sprayers come in many configurations. The flow rates for micro sprays can add up fast. See the chart at the end of this section for micro jet flow rates.

 

 

 

 

Adjustable Stream Bubbler Full Circle:                       Adjustable Stream Bubbler Half Circle:

 

 

 

MICRO SPRAY CAP & BASE PERFORMANCE
Black Base, .030" Opening (DD-MSB30)
Arc	Pressure	Radius	Diameter	Flow
	psi	ft	ft	gpm
DD-MCF	10	-	10.2	4.7
360 Degrees	15	-	13.4	5.9
	20	-	14.7	6.9
	25	-	15.6	7.8
	30	-	16.4	8.6
DD-MCH	10	4.4	-	4.7
180 Degrees	15	5.0	-	5.9
	20	5.4	-	6.9
	25	5.6	-	7.8
	30	6.7	-	8.6
DD-MCQ	10	4.4	-	4.7
90 Degrees	15	5.7	-	5.9
	20	6.6	-	6.9
	25	7.2	-	7.8
	30	7.7	-	8.6
Blue Base, .040" Opening (DD-MSB40)
Arc	Pressure	Radius	Diameter	Flow
	psi	ft	ft	gpm
DD-MCF	10	-	13.4	7.0
360 Degrees	15	-	15.8	8.9
	20	-	18.2	10.5
	25	-	19.6	12.0
	30	-	20.4	13.3
DD-MCH	10	5.2	-	7.0
180 Degrees	15	6.0	-	8.9
	20	6.4	-	10.5
	25	6.6	-	12.0
	30	7.0	-	13.3
DD-MCQ	10	4.7	-	7.0
90 Degrees	15	6.1	-	8.9
	20	7.6	-	10.5
	25	8.2	-	12.0
	30	8.6	-	13.3
Green Base, .050" Opening (DD-MSB50)
Arc	Pressure	Radius	Diameter	Flow
	psi	ft	ft	gpm
DD-MCF	10	-	17.4	11.5
360 Degrees	15	-	21.1	14.5
	20	-	22.5	17.2
	25	-	23.3	19.5
	30	-	23.8	21.5
DD-MCH	10	5.7	-	11.5
180 Degrees	15	6.6	-	14.5
	20	7.2	-	17.2
	25	7.8	-	19.5
	30	8.4	-	21.5
DD-MCQ	10	5.8	-	11.5
90 Degrees	15	7.4	-	14.5
	20	8.4	-	17.2
	25	9.1	-	19.5
	30	9.6	-	21.5
Red Base, .060" Opening (DD-MSB60)
Arc	Pressure	Radius	Diameter	Flow
	psi	ft	ft	gpm
DD-MCF	10	-	18.4	16.3
360 Degrees	15	-	22.6	20.0
	20	-	25.7	23.5
	25	-	26.3	26.0
	30	-	26.7	29.0
DD-MCH	10	6.7	-	7.0
180 Degrees	15	8.1	-	8.9
	20	9.5	-	10.5
	25	10.1	-	12.0
	30	10.6	-	13.3
DD-MCQ	10	6.4	-	7.0
90 Degrees	15	8.1	-	8.9
	20	9.4	-	10.5
	25	9.8	-	12.0
	30	10.8	-	13.3

 

3. Retrofitting an Existing Sprinkler System

Sprinklers can be converted to drip in a number of ways. Pressure compensating bubblers and emitters can be attached directly to 1/2" threaded risers. Simply unscrew the existing sprinkler or shrub head and replace it with the emitter or bubbler. Our 6-outlet drip bubblers allow you to run 1/4" drip tubing to up to six plants. The bubblers come with one outlet open. You can cut the tip off of closed outlets with a utility knife. They deliver a lot of water and are a good choice for deep-watering trees.

The single-outlet emitters are best for watering individual plants. Both emitters and bubblers can be installed at 90° angles by using a Marlex elbow, as shown in the photos.

 

4. Drip Emitter Tubing vs. In-Line Emitters

Drip Emitter Tubing has drip emitters extruded into the tubing itself. It comes in rolls of 100 feet or more. It is used in row plantings, vegetable gardens, and anytime that a long, even-spaced run is required. It can be purchased with 1/2 gph or 1gph emitters at a variety of spacings and comes in 1/4" & 1/2" (700) tubing sizes.  The emitters in the 1/2" tubing are pressure compensating. They will maintain the same water flow regardless of fluctuations in pressure.  The 1/4" emitters are non-pressure compensating. The water flow will vary with fluctuations in pressure. This makes it a good choice for low pressure and gravity fed systems. It is easily wrapped around trees, shrubs, borders, & flower beds. Install in rows for small vegetable gardens, raised planter boxes, and window boxes.

 

Use scissors to cut 1/4" tubing and clippers to cut 1/2" tubing.

 

 

 

 

 

 

1/4" Drip Emitter Tubing (Soaker Line) is available in the following configurations:

100' roll, 1/2 gph emitters, 6" spacing

100' roll, 1/2 gph emitters, 12" spacing

 

Install with 1/4" barbed fittings. Since the emitters in 1/4" drip emitter tubing are non-pressure-compensatings, the output of each emitter with vary with changes in pressure. We recommend installing a 20 psi regulator.

 

1/4" Drip Emitter Tubing - Operating Specifications

Pressure     Flow Rate Per Emitter

 

1/2" Drip Emitter Tubing (.700" O.D x .600" I.D.) is available in the following configurations:

1/2 gph emitters, 12" spacing - 100' roll

1/2 gph emitters, 12" spacing - 400' roll

1/2 gph emitters, 18" spacing - 100' roll

1/2" gph emitters, 18" spacing - 400' roll

1 gph emitters, 18" spacing - 400' roll

1 gph emitters, 18" spacing - 400' roll

 

Install with 1/2" compression fittings. Since the emitters in 1/2" drip emitter tubing are non-pressure-compensatings, the output of each emitter saty the same, even with changes in pressure.  They are self-flushing and clog resistant. We recommend installing a 20 psi regulator or 30 psi regulator, and a filter with 120 - 150 mesh screen.

Emitter Tubing Guidelines
Tubing Size & Emitter Spacing	Pressure Compensating Emitters?	Max psi	Max Run per branch	Max Run Total           (1/4" is fed from 1/2" mainline)
1/4" Tubing - 6" spacing 1/2 gal/hr	No	30	19 ft	200 ft
1/4" Tubing - 12" spacing 1/2 gal/hr	No	30	33 ft	400 ft
1/2" Tubing - 12" spacing 1/2 gal/hr	Yes	50*		450 ft
1/2" Tubing - 18" spacing 1/2 gal/hr	Yes	50*		500 ft
1/2" Tubing - 18" spacing 1 gal/hr	Yes	50*		350 ft
* We recommend operating at 20 - 30 psi

 

Pressure Compensating Emitters

• Deliver the stated gph (gallons per hour) even if pressures range is 10-50 psi
• Works well with elevation changes
• Self-flushing to reduce clogging

Non-Pressure-Compensating Emitters

• Output will vary with changes in pressure & elevation
• Workes best with flat landscapes
• Excellent for gravity-fed drip systems

1/2" Compression Fittings

• Recommended pressure: 10-30 psi
• Max pressure: 60 psi

 

In-Line Emitters

If you don't have a long run or you have uneven plant spacings, you can make your own custom drip emiiter tubing with in-line emitters. Simply cut 1/4" micro tubing to the desired lengths and attach it to the barbs on either side of the in-line emitter.

 

 

 

Compare All Our Drip Emitters

Still not sure which type of emitter to buy? This handy chart should help: Compare all drip emitters.

Designing and Planning Your Drip Irrigation System

 

Design Watering Zones by Plant Groups

- Flower Beds & Ground Cover
- Trees & Shrubs
- Vegetable Gardens
- Containers, Pots & Boxes

Plants of similar sizes and growth habits generally have  watering requirements that are much the same. Always try to group watering zones by plant moisture needs and local climate conditions (shade, partial shade , full sun). 

Consider the following:

 

• Plants that need frequent, shallow watering, like annual flowers and ground cover, should be grouped separately from those needing less frequent, deep watering, like trees.

• Seasonal plantings like crops or vegetable gardens should be kept separate from permanent plantings like shrubs. Install inexpensive flow control valves to shut off these areas when not in use.

• Create separate zones for plants in the shade versus hot, sunny spots.

• Container plants should be watered separately from plants in the ground. They have confined root systems and may dry  out more quickly.

 

Determine Your Soil Type:

Water puddles in hard, tightly bound soil and may eventually runoff. Apply water slowly to clay soils so that it has time to penetrate into the root zone. In sandy soils, water flows down in a narrow pattern. Space emitters closer together to ensure full coverage of the root zone. The guidelines below will help you plan for your specific landscape.

 

Sandy Soil (loose): Grip a handful tightly, when released it will fall apart.

Loamy Soil (normal): Grip a handful tightly, when released it will hold together, but can easily be broken apart.

Clay Soil (hard): Grip a handful tightly, when released it will hold together and is not easy to break apart.

 

Emitter Recommendations by Plant & Soil Type:

 

     Flower Beds & Ground Cover - Sandy Soil

 

Individual Plants

Drip Emitters (1gph):

1 gph PCE Drip Emitter

Drip Emitter Tubing (1/4" tubing, size 250):

1/2 gph at 12" spacing - 100 ft roll

Groups of Plants

Large Plants

Drip Emitter Tubing (1/2" tubing, size 700):

1/2 gph at 12"spacing - 100 ft roll

1/2 gph at 12" spacing - 400 ft roll

Small Plants

Drip Emitter Tubing (1/4" tubing, size 250):

1/2 gph at 12" spacing - 100 ft roll

Spray fittings:

Micro Jets-Sprayers

 

Rows of Plants

Drip Emitters (1/2 gph, 1gph):

1 gph PCE Drip Emitter 

Large Plants

Drip Emitter Tubing (1/2" tubing, size 700):

1/2 gph at 12"spacing - 100 ft roll

1/2 gph at 12" spacing - 400 ft roll

Small Plants

Drip Emitter Tubing (1/4" tubing, size 250):

1/2 gph at 12" spacing - 100 ft roll

 

 

     Flower Beds & Ground Cover - Loamy or Clay Soil

 

Individual Plants

Drip Emitters (1/2 gph, 1gph):

1/2 gph PCE Drip Emitter 

1 gph PCE Drip Emitter

Groups of Plants

Large Plants

Drip Emitter Tubing (1/2" tubing, size 700): 

1 gph at 18"spacing - 100 ft roll

1 gph at 18" spacing - 400 ft roll

Small Plants

Drip Emitter Tubing (1/4" tubing, size 250):

1/2 gph at 12" spacing - 100 ft roll

Spray fittings:

Micro Jets-Sprayers

Rows of Plants

Drip Emitters (1/2 gph, 1gph):

1/2 gph PCE Drip Emitter 

1 gph PCE Drip Emitter

Large Plants

Drip Emitter Tubing (1/2" tubing, size 700):

1 gph at 18"spacing - 100 ft roll

1 gph at 18" spacing - 400 ft roll

Small Plants

Drip Emitter Tubing (1/4" tubing, size 250):

1/2 gph at 12" spacing - 100 ft roll

 

 

     Trees & Shrubs - All Soil Types

Small Shrubs & Roses (up to 4' high)

1-2 Drip Emitters per plant (2 gph-Sandy,1 gph-Loam, 1/2 gph-Clay):

2 gph PCE Drip Emitter

1/2 gph PCE Drip Emitter

1 gph PCE Drip Emitter

Drip Emitter Tubing (1/2" tubing, size 700).

Tip: Loop emitter tubing around base of plant for best coverage.

1/2 gph at 12" spacing - 100 ft roll (Clay & Loam)

1/2 gph at 18" spacing - 100 ft roll (Loam)

Adjustable Stream Bubblers

Stream Bubbler on Stake - Full Circle

Stream Bubbler on Stake - Half Circle

Stream Bubbler with barb - Full Circle

Stream Bubbler with barb - Half Circle

 

Medium Shrubs & Trees (2' to 4' high)

2 Drip Emitters per plant (2 gph-Sandy,1 gph-Loam, 1/2 gph-Clay)

Tip: Install 12" from base of plant on either side

2 gph PCE Drip Emitter

1/2 gph PCE Drip Emitter

1 gph PCE Drip Emitter

Drip Emitter Tubing (1/2" tubing, size 700).

Tip: Loop emitter tubing around base of pant for best coverage.

1/2 gph at 12" spacing - 100 ft roll (Clay & Loam)

1/2 gph at 18" spacing - 100 ft roll (Loam)

Adjustable Stream Bubblers on a stake

Stream Bubbler on Stake - Full Circle

Stream Bubbler on Stake - Half Circle

Stream Bubbler with barb - Full Circle

Stream Bubbler with barb - Half Circle

 

 

Larger Shrubs & Trees (4' to 6' high)

2-4 Drip Emitters per plant placed in a loop around the tree canopy

Sandy Soil: 4 - 2 gph emitters 2 gph PCE Drip Emitter (12" - 18" spacing)

Loamy Soil: 2 to 3 - 1 gph emitters 1 gph PCE Drip Emitter (18" spacing) 

Clay Soil: 4 - 1/2 gph emitters 1/2 gph PCE Drip Emitter (12" - 18" spacing)

 

Drip Emitter Tubing (1/2" tubing, size 700).

Tip: Loop emitter tubing around base of plant for best coverage.

1/2 gph at 12" spacing - 100 ft roll (Clay & Loam) 

1/2 gph at 12" spacing - 400 ft roll (Clay & Loam) 

1/2 gph at 18" spacing - 100 ft roll (Loam) 

1/2 gph at 18" spacing - 400 ft roll (Loam)

1 gph at 18" spacing - 100 ft roll (Loam & Sand)

1 gph at 18" spacing - 400 ft roll (Loam & Sand)

 

Large Trees (6' and up)

5 Drip Emitters per plant placed in a loop around the tree canopy

Sandy & Loamy Soil:  2 gph emitters 2 gph PCE Drip Emitter (12" - 18" spacing)

Clay Soil: 2 gph emitters 2 gph PCE Drip Emitter (18" - 24" spacing)

Drip Irrigation - History & Benefits

 

Drip Irrigation, also commonly referred to as micro-irrigation, trickle irrigation, low volume irrigation or xerigation. This is a method of irrigation which very efficiently delivers water to the soil surface or the root zone; this is done by having water drip slowly from emission devices, most commonly called "drip emitters" or “drippers”.

Early forms of drip irrigation can be traced back to ancient times where clay pots were filled with water and then buried in the ground, this allowed the water to gradually leak out and into the root zone of nearby vegetation. The first formal development of drip irrigation supplies began around 1866 in Afghanistan, where they tested drip irrigation and drainage systems by using various types of clay pipe. A researcher at Colorado State University, Mr. E.B. House, began applying subsurface water directly to the root zone in 1913. Perforated Pipe was first used for irrigation in Germany around 1920.

 

After WWII the ability to mold plastics became widespread and more cost effective. This helped pave the way for innovations in the manufacturing of drip irrigation system components. At this time, Polyethylene (PE) tubing, also referred to as "micro tubing" or "spaghetti tubing", and early versions of emitters (drippers), became more common and was installed throughout the US and Europe. In Israel, Simcha Blass & Yeshayahu Blass were innovating in the area of emitter design. They created a method for water to flow through longer and wider passageways inside of the emitter. These “labyrinths” allowing for less clogging. The velocity of water moving through the labyrinth, and resulting turbulence, helps to slow it down, creating a "drip". In 1959 Kibbutz Harzerim partnered with Blass to form a company called Netafim, to further develop and test this concept. Netafim was then able to patent the first drip irrigation emitter. This development helped the technology of drip irrigation rapidly expand to Australia, North America, & South America in the late 60's.

Here's a list of all the parts discussed in this tutorial.

For a complete listing of all our irrigation products, view our catalog online (pdf) or we'll mail you one.