Many tree nurseries have hundreds of containers mostly sized 5 gallon and up. These trees are constantly being moved as they are being sold. Most use a drip system employing emitters referred to as "spitters", which are in the form of plastic stakes. They connect to 1/2 inch drip tubing with 1/8 inch tubing. They are available in several different gallons per hour, color coded to make selections easy. When a pot is removed the spitter is inverted which seals it from leaking until another pot fills the spot and is reconnected. Any irrigation supply should have them. I buy mine from www.harmonyfarm.com. Al

I installed the Mister Landscaper kit four years ago from which I am watering 25 containers. Works well. No problems. Available at Lowes.

I began the installation by screwing in a double Y faucet connection which allows me to run the drip system on one side and use a regular hose on the other side. Then the timer was inserted on one side of the double faucet which in turn was connected to a 2" pvc pipe long enough to go from timer into the ground, an elbow added and the pipe continued in a covered trench to the container area. Then the flexible tubing into which the leads are plugged was installed onto the pvc pipe. Leads were plugged in and cut to lengths needed (give yourself some extra play) and the dripping devices inserted at ends. All this takes a bit of fitting but is easy to figure out. The company has helpful tips on line.

The timer works well through the growing season without the need to replace the battery. I water here from March into December setting the timer to water once a day for 25 minutes. I have two leads into my large tree pots where I grow shrubs and tomatoes, one lead for smaller pots. Growing in the gritty mix everything is thriving and I am not out in 100 degree temperatures hand watering and guessing how much water each pot needs. That 25 minute 'drink' is all that is needed in this hot climate.

I just switched over to a drip system away from a SWC system.

One issue not discussed yet is that when you use one dripper for a container with a fast draining mix, much of the container soil will stay completely dry, even after watering. The water drains down from the drip emitter and doesn't spread out much. You won't even know this unless you dig up the soil after a watering to check it out. Your plant will probably look fine, but in effect it will be growing in much less soil volume than it could be, like growing in a smaller pot. This isn't a problem in peat mixes, where the water spreads out easily.

I used a drip line segment with 5 emitters in it for each container and this still wasn't enough to fully wet the 18" diameter containers I use. I'll be switching to 12 emitters per container next season.

To determine the number of emitters you need for "full mix wetting". Take a container with just your mix in it. Start with the mix dry, then water it using just one drip emitter. Use the emitter that you've chosen for your system. Wait awhile (hour or so) so that the water has a chance to spread out. Then by carefully digging down in layers, determine the diameter of the area that is wet. Then you figure out how many emitters are needed and how they should be spaced in the container.

For my mix I determined the water spread out in a circle "one finger length" in diameter. Then just by moving my finger around the pot I could see I'd need 12 of them for complete wetting.

Some people use micro sprayers or a coil of mini soaker hose in a container to get a full wetting, haven't tried these myself. With emitters I get more control over how much and where the water goes.

Em: Uggh! This wasn't the news I was hoping for! Based on what I have right now, I would need ~60 emitters for 5 containers. Are you using Al's gritty mix? What is your gallon rate per hour?

And, just for laughs, what finger were you using? I have small hands!!! :-O I might need 120!

Fifteen years ago when I was doing classes on irrigation, I made up two boxes, each one foot cubes. One side of the box was Plexiglas. One box was filled with sandy/loam soil the other with clay/loam. A one gallon plastic jug such as milk comes in was placed on top of the open top of each box. A one gallon emitter was inserted in the side of each jug close to the bottom. At the beginning of my talk I filled each with water. In one hour both jugs were empty and everyone could see the shape of the water pattern through the plexiglas. The point was to illustrate the difference,of the wet area in different soils. You could use any soil mix to test the wet area pattern, as that seems to be your concern. Al

retiredprof,

Actually I was using just leaf and pine needle mold for my mix with a little dirt. I did the same water pattern experiment with a 50:50 bark:turface mix and got similiar results.

12 emitters per large container isn't too bad. I use drip line with emitters spaced every 6". Each emitter is 1/2 gallon per hour flow rate. Just lay out the drip line in a spiral formation on the soil and hold it in place with wire loops I cut from coat hangers. I use many long wire loops, ~6" per side in order to hold the drip line down firmly in place. You might want to try just 1 micro sprayer.

Cheers