Zackman, last year I bought a "Misty Mate" patio mister at Wal-Mart which I'm planning to use this summer. It has 10 ft of mist line, 10 ft of supply line and all the hardware. It was about $15. I'm going to run it along the long side and put it on a timer.

My father had a misting system in this GH years ago, but I have no idea how to get it going again. This should do until I can figure his sytem out.
Good luck
Sunny

Unless you enjoy fiddling with the stuff, I don't recommend PVC. Just get the flexible black pipe, and the heads screw directly in after you punch a hole.

If you grow mostly potted plants, you can use a heavier spray that will deliver more water, more quickly. I grow orchids, most of which are mounted or in baskets, so I use 5-7gph heads for a lighter spray that's run longer, so I can be sure of a good soaking.

If your goal is more for cooling, then you need .75gph heads. However, if cooling is your goal, then I wouldn't recommend overhead misting. It would keep your plants constantly wet, and beyond being overly moist, having wet plants at night invites fungus, rot, and botrytis on your blooms.

Yes, you can turn on and off individual heads...if you rig it up that way. You just need to install separate "arms" for those heads you want to control separately, and fit a valve ahead of them.

I've installed over a half-mile of 3/4" mainline tubing on my property for various irrigation zones, including standard sprinkler heads, drip irrigation, and micro irrigation, in addition to the misting/watering system in my gh -- which has a separate structure for chilling incoming air utilizing the .75gph fogging heads I mentioned. The gh uses 1/2" mainline tubing.

I use no auxiliary pumps, and everything is operated off of well-pressure, which runs from 45 to 70psi. Water to the gh comes from a line from a house spigot, so it's filtered through a bubbler and two charcoal canisters. I use no other filter for the gh. Since my other irrigation zones bypass the charcoal canisters, they go through a 200-mesh screen.

I've operated the watering and cooling schedules for my gh by hand for a long time, but just ordered the Orbit 4-Valve Battery Timer to take care of that for me.

All of my supplies were purchased from DripWorks, except for the timer.

-Bruce

Bruce, your water supply that comes off a house spigot: I haven't hooked mine up yet and was wondering about how to do it. I am also on a well and we have a water softener installed at the well so all the water coming into the house gets treated. We have the under-counter unit that re-treats water for drinking and cooking. So if I ran a line from an outside spigot or straight from the well, to the gh it would be the 'salinated' water and I don't think that's what I want in there. But I also don't want the straight well water either since it's very high in iron and copper and clogs everything it flows through.

So can you explain to me how I get good quality water to the gh, and use small words because I'm not real smart about these things, please. Cheryl

Hi Cheryl --

You're going to need some additional equipment, but it's "doable." You'll need a reverse osmosis filter for your gh and swamp cooler. You'll need to estimate your watering needs, and the swamp cooler should have an estimated water consumption number as part of the specifications. This will guide you to the correct size for the filter.

Reverse osmosis filters require some maintenance as far as cleaning/replacing the filter membrane, as well as periodic back-flushing. Another issue with reverse osmosis is the water is actually too "pure" for optimal orchid health. There are methods to add back in a bit of minerals to the water occasionally. At any rate, this isn't a serious issue, and can be accomplished with a fertilizer applied with a hand-sprayer.

So that you don't overly-tax the filter, you don't want to use the softened water from your house. It'll actually be better for the filter to use well water.

I'm not experienced with using reverse osmosis, and can't advise you as far as specific details. However, I know that Andy's Orchids uses reverse osmosis on their inventory, and are wonderful folks. Give them a call, and ask to speak with Andy or Harry.

-Bruce

Here is a link that might be useful: Andy's Orchids

Thanks for responses. Bruce, you caused me to think about how I may use a misting system. I will definitely use it for cooling - as I anticipate needing that, but I was also thinking about using it to water if I am not here for a few days - I would have that hooked to a timer. (I have also put the pots in a shallow plastic bin with a half inch or so of water with good results when I am not here).
Anyway, I may need to hook up two systems - one for watering and one for cooling. You indicate that if it is for cooling it should not be overhead - where would I put the misters installed just for cooling.
I just hosed down my benches and the brick floor and even that cooled things down a bit.
We will be using the gh for seedlings and vegetables (I have probably 60-70 plants growing now and about that many in seed starter bins) but will also try our hand at flowers. . . my wife put some in there already and they are taking off. . .and she wants to learn about orchids. . .

If you don't have anything below your benches, what you need to install is an "under-bench" system. Place a separate line to run water underneath your benches, with .75gph fogging heads placed in a staggered pattern to maximize coverage. In order to get the largest benefit from such a system, your incoming air must be drawn through the fog, which means the position of your vents must be near the floor. The Orbit timer I mentioned above would serve your purpose well, covering two different zones...one for watering and the other for cooling.

Many prefab, hobby gh's use a passive venting arrangement with roof vents, but this simply does not provide optimal cooling. Designing proper airflow through a gh with a reasonably powerful exhaust fan makes a huge difference in the interior climate.

If you can't easily redesign or reposition your intake vents, then you can build a poor-man's swamp cooler by placing blue plastic spun filter material (available at big box stores) in the air stream, and have your fogging heads spray upstream into the material. Just having one or two of these filter pads is not likely going to be enough to do the job you need -- this is why I built a separate structure on my intake for just this purpose. Depends upon your cubic volume, desired temperature, and ambient humidity.

-Bruce

You don't have to install misters under the benches to mist for cooling. I cool with overhead misters.

You only get any cooling when the water evaporates, right? So whether you end up cooling the GH or watering the plants will be determined by emitter flow rate, emitter droplet size, and timing of your misting cycle. The greater the droplet size, the greater the flow rate, and the longer the cycle runs, them less chance those water droplets will vaporize and absorb the heat and the greater likelihood they will end up in the container media (watering the plant) and the greater likelihood they will persist on the foliage and result in disease.

Misting doesn't burn plants. Think about a misting bench. What you were told is a myth, inside the GH or outside.

The biggest issue I have seen is that of water quality. Ten days of misting with hard well water and you will have an absolute mess in terms of calcium buildup on plants and GH benches and walls. So I only use RO or rainwater for misting.

I suppose it depends upon what you're trying to grow. In order to control the kind of temperatures I have here in the Florida panhandle, I'd be misting regularly, for long periods of time during the warmer months. This would be death to my orchids, since prolonged wetness in leaf axils, and having the potting medium (for those I have in pots) too wet, causes rot. (When I water, I must do this in the early morning so that any residual droplets have evaporated by the time night falls.) I would also think that having small seedlings wet would invite problems too.

It's logical to wonder, "Yes, but it rains at night in nature." It does, but there is usually air movement present, and the infinite capacity of the volume of air can continue to absorb vater vapor from evaporation. Also, the plants that grow in those tropical places where nighttime rains can be often, are adapted to those conditions. As ghers, we want to grow what pleases us, from varying climates and locations around the world. We must compromise, and understand the limitations of a closed, confined system to keep it hospitable.

In more temperate locations, rains are usually infrequent, such that things can dry out between downpours. In a gh this would be different, because in order to keep things cool, misting must be done regularly, daily.

Perhaps mature tropicals, and larger, woody plants, can tolerate the wetness -- especially if the misting isn't directly overhead. I noticed the photos of your gh, stressbaby, on your homepage...and it's massive. Is it possible the extra space allows you to avoid wetness issues? The larger interior volume increases the overall potential for evaporation for a given level of humidity, as well. By comparison, I don't have much space, either laterally or overhead, in my 8x14 gh.

I suppose what this indicates is that there are several factors to be considered when designing a cooling system:

1) interior volume of gh
2) desired plants
3) desired interior temp vs. outside ambient
4) average ambient humidity (because this controls the degree of evaporation)
5) CFM of exhaust system vs. interior volume

#4 is particularly important, because not only does humidity dictate the effectiveness of any method of cooling, but if it is high it also will restrict evaporation of water off of plants.

-Bruce

Bruce, I agree on all points. Zacman is in zone 9, so perhaps he is better off using your advice than mine after all!

I have a very large swamp cooler - now on the roof of our house and which has not been used for years - and never used much at all as after we installed it, we decided we did not care for it. I have planned to take the evap cooler down and install some sort of a whole house fan set up as it cools down nicely in the evenings here in the foothills even in the summer. I may then try to use the evap cooler for the green house but it is large and is a bottom opening unit - I could make it work but it would take a bit of work. .. I will have to think about whether it is worth it. Certainly, there would be minimal cost as I already have the unit, and if my wife is serious about orchids it may be the way to go.
As for a misting system, I think I will install one hooked to a timer and used to water plants if I am going to be gone. I will wait to see how things work out in the summer with shade cloth and other systems. ..for example, just hosing down the bricks and rocks inside really cooled things down yesterday. Thanks for taking the time to provide advice. . it is much appreciated.