The drip irrigation installation

Here’s more info on the drip irrigation.  I’m sharing this because of a comment (this is long overdue – sorry!) from the last drip irrigation post requesting more pictures.  That reminded me that I had a terrible time finding information myself on drip irrigation.  There is an excellent guide that a neighbor told me about at Toro.  It was way too detailed and technical for me, though.  I wasn’t going to be investing in tons of equipment, filters, pressure regulators, etc.  I just wanted to hook a few tapes to a barrel and call it a day.  Well, I just set out one afternoon and hooked it all up to see if it worked.  It did!

Here’s some more pictures and detailed descriptions on how I did it:

This is the 2″ threaded PVC nipple installed in the hole near the bottom of the barrel.  It is attached with JB Weld.  Then a brass shutoff valve in installed before finally connecting the hose.

I use garden hose as my supply lines.  Using a drill bit in my cordless drill, I placed holes where I want my drip tapes.  The above blue thingy has  a barb on one end that connects to the hose and a tape lock nut on the other end to grip the tape.  The brand is Netafim and I got them from Farmtek.  Each drip take has its own shutoff valve.

Another view.  I have noticed better performance where I set the barrel to be higher than the beds.  Gotta love gravity!  Using a few cement blocks or some scrap 2×4 shims will do the trick.

We are using uniform bed sizes everywhere, measuring 30″ wide and 20′ long.  Another benefit to that decision is that the feeder lines and drip tapes can be gathered up and reused next season as long as we make the beds the same size again.

After using it for several months, there are a few things I’d like to point out.  First, the epoxy breaks very easily.  At one point, I had a shovel or hoe leaning on the barrel and I bumped it.  The tool fell right on the pipe that is sticking out of the barrel, broke the seal, and the water began leaking.  Another time, I bumped the pipe with my foot and broke the weld.  Applying a second, heavier layer of epoxy does help strengthen, but I’d be interested in researching a new idea, such as putting a nut on the inside and outside with rubber washers sandwiched in between.  That would be much stronger.  That’ll go on the list of projects for the winter.

Another concern has to do with the potatoes.  When I hilled them up, I buried the driptapes.  Shouldn’t be a problem, I speculated, since this tape is designed to be buried up to eight inches in soil in commercial applications.  Those same commercial application, however use an irrigation pump to achieve the optimum amount of water pressure in the lines.  Using my gravity based system the pressure is much lower.  The lines in the potato beds are buried under several inches of our clayey soil and are pinched.  Some of the beds don’t have water going to the ends and the potato plants are drying out.  I’m resorting to hand watering for those spots and it’s getting old.

Thanks, Robert

Drip irrigation

We love our arid climate, but realize that it can make gardening a challenge.  On average, we get less than fifteen inches of rain per year, which is almost 1/3 of what I am used to growing up in Pennsylvania.  In an attempt to provide more consistent and conservation-minded water to our garden we’re installing a drip irrigation system utilizing 5/8″ drip tape gravity fed from 55 gallon plastic barrels.

In the above picture, you’ll first see that I have elevated the barrel on a few cinder blocks in order to create slightly more water pressure from gravity.  The barrel was originally a white color and I painted it black so that a.) sunlight penetration is reduced which will prevent algae growth and b.) the water will heat up in the barrels.  Using warmer water will reduce shock that the plants might have if the water was colder.  A threaded PVC nipple was JB Welded to the side of the barrel one inch up from the bottom.  It is one inch above the bottom because I don’t want to draw any sedimentation into the lines that may collect at the bottom.  Between that and the hose I have a brass shutoff coupling.  The supply line running between the beds is the cheapest garden hose I could find.  I cut pieces to fit each row of beds.

Each bed has two driplines running down the length of the bed.  Beds, by the way are 30″ wide and 20 feet long.   Everything is uniform, which will allow interchangeability.  We plan on getting several years usage out of the tapes and this way we can easily install them next year, not needing to worry about where each tape goes.  Each tape line begins at the supply line, coming through another shutoff valve.  That shutoff valve has a barb on one side that you push into the hose (I used a cordless drill to make the appropriate size holes in the supply hose first) and the other side connects via a coupler to the 5/8″ drip tape.  The tape and the shutoff valves are from Farmtek.  At the other end of the tape, fold it over on itself twice to crimp closed and then fold lengthwise.  Then slide a 1″ section of drip tape over the fold to hold it together.

Having every line on a valve gives you maximum control of water.  Some beds contain a crop that is harvested early in the season, and once done you could turn that bed off to save water.

To calculate how much water you’ll need, we estimate that each bed will need 1″ of water per week.  A bed if fifty square feet.  That translates to ( 50 / 12 x 7.48 ) 31.16 gallons per bed per week.  Said differently, I’m dividing fifty by twelve to find the cubic feet of water that 1 inch of rain on that bed would represent.  One inch of rain would be 1/12th of a cubic foot of rain.  One cubic foot of rain water on a 50 sq ft bed is 50 cubic feet and that would be twelve inches of rain.  Then convert to gallons by multiplying by 7.48.  Most of our lines are set up to water seven beds at once and I assume (perhaps incorrectly) that each bed is getting an even amount of water.  So, you could fill your barrel to the 30 gallon mark every day of the week and know that all seven beds are getting 1″ of water over the course of seven days.

Thanks, Robert.

Container Gardening

We’re back to container gardening this year and wanted to share a few pics and comments on how we are doing it.

Begin with your barrels.  Be a scrounger and find them for free like I did.  The 55 gallon size is great because you can cut them to make two planters.  Be careful on what the previous contents were.  Mine had soaps and other cleansers in them.  Rinsing them out twice should get most of the stuff out.

And here is my beautiful wife on a sunny day, drilling the drain holes into the bottom.  I put four 5/8″ holes spaced evenly and in the low spots. Yes, she is pregnant, and no, I didn’t make her do this.  She wanted to be outside in the sun.  We had fun.

Before filling with dirt, I covered each hole with a rock.  That way there is a small gap where excess water can drain.  Dirt could become compacted and clog the hole.  Proper drainage is very important so that the roots don’t rot from sitting in too moist an environment.

Begin filling with soil, being careful not to move those rocks covering the drain holes.

We filled to the top with compost.  We got free compost from a friend who owns a dairy farm.  This was dairy manure that was composted for two years and was screened.

We put three tomato plants in the tomato tubs.  Four pepper plants in the pepper tubs.  You can also see the square box in the background.  That will be our lettuces, beans, etc.

Thanks, Robert.