Nice chunk of equipment, but I don't think it's ideal, especially since it can only handle 150 watts (think one good-size light bulb) and since it has low voltage capability that you probably won't use. You need a regular electric circuit, especially if you want heat in the winter, because most small heaters are 1500 watts, and you will need at least a standard 15 amp circuit (which can handle 1800 watts).

Your best option is to run plastic conduit from the nearest source out to the greenhouse with 12 or 14 gauge wiring that's certified for underground use. Then install a standard GFI receptacle inside a box with a weatherproof cover at the end of the run inside the greenhouse. [Below is a link that shows the kind of kit you need for a wet location.]

This will be some work, but it's what you'll need to do to have adequate power that's installed in a safe manner. You can then plug in thermostats directly into the outlet. There are a number of weatherproof thermostats available for various greenhouse purposes. I have this kind of arrangement and use one of the plugins for my thermostatically controlled fan and my thermostatically controlled seedling mats. In the winter, I have an inexpensive, oil-filled heater with a built-in thermostat to keep my greenhouse above freezing. If you think you'll need more than two plugins, you could get a duplex box (two receptacles wide) and a matching weatherproof cover.

Here is a link that might be useful: Wet location box

Thank you for your help! I hadn't noticed the watts thing -- you're right, that wouldn't work. I wish I could just use an outdoor extension cord with a weather-proof extension cord cover (found them in my search, too, at this link: http://www.littlegreenhouse.com/accessory/electrical.shtml) but I guess that wouldn't be too safe for extended periods. And the only way I could probably get that to work properly is if I somehow had the extension cord plugged in to a timer or thermostat from the covered patio and had it figured out exactly what times or temperature outside the greenhouse it would need to come on.

My main concern is having something set up for when we are out of town. We have someone who can open/close the greenhouse in the morning and night and water if necessary, but they can't constantly monitor the temperature throughout the day.

Thank you for the link. It's looks somewhat similar to some of the boxes at the link in this post, so I'm wondering if those would work as well? The one you provided looks a little more heavy-duty, though. I was afraid I wouldn't be able to get away with doing it a really easy way, lol!

I think your misters need to fire for shorter periods more frequently. One hour every 4 hours, without a powered exhaust fan, and you may be basically watering, not misting.

Mine go one for 10-15 seconds every 10 minutes.

I agree with Kudzu, put in a line.

I looked at your link at the littlegreenhouse site and those look entirely equivalent to the ones in my link. I would simply recommend that you use non-metallic (plastic) conduit rather than metallic, and that you get the deepest box cover you can because a lot of grounded plugs take up quite a bit of room and you want to be able to close the cover fully if you're doing misting.

Thank you both for your advice! I agree that I need to use the misters for shorter bursts, but my timer doesn't allow it. I spent about $35 for my water/mister timer. Is there one you can recommend that will let me do short bursts more frequently? I have seen some, but the cheapest was about $85. If I have to spend that much, that's fine but the less I can spend for quality, the better.

I'm thinking that if I could do a mister in shorter bursts, I may not even need the electricity until the winter because I can just use a few more high-powered battery fans during the hot hours combined with the shorter misting times and keep the temps what I want. I would spend less money that way, too.

If I can wait until winter when I won't be using the mister, I may even be able to get away with using a heavy-duty outdoor extension cord to use a heater at night sometimes, or some other low-powered heat source that would provide just enough heat to keep it above freezing in there.

Any mister timers you can recommend would be appreciated!

Just a suggestion...outdoor extension cords are meant for temporary connections, not continuous hookup for months at a time. Electric heaters draw a lot of juice, and some are not rated for use with extension cords. In addition, if you were to have a fire resulting from using an extension cord for a "semi-permanent" application, your insurance company might be a little grumpy to deal with.

I use a two zone version of this one: http://www.hummert.com/catalog.asp?P=4729 The two zone version has been discontinued, they now make only a one zone and six-zone version. Extremely reliable and easy to operate. Looks like this one is $213 at Hummert.

Much cheaper is this 6 zone timer for $80: http://www.mrdrip.com/propagationtimers.htm but just looking at the website, it is not evident that there are enough "start times."

Here is another in the $80 range: http://www.sprinklerwarehouse.com/5006-IP-AC-6-Station-Controller-p/5006-ip.htm

You always have Melnor timers, but concerns about reliability always bothered me: http://www.amazon.com/Melnor-Electronic-DUO-AquaTimer-3060/dp/B00004SDVT/ref=pd_bbs_sr_1/104-9506542-2562339?ie=UTF8&s=hi&qid=1186252451&sr=8-1 However, it is inexpensive and battery operated.

HTH

SB

Good point, kudzu9. If I did do that, it would only be at night and not every night, maybe even just for a few warming mats (would that work?). But you're right, insurance wouldn't be happy if something were to happen!

Thanks for the timer links. I'll take a look at them. Anyone have experience with this one? http://www.charleysgreenhouse.com/index.cfm?page=_productdetails&productid=3356&s=timer&cid1=-99&cid2=-99&cid3=-99

That looks like a good one: being prewired, being continuously variable, and having a photocell are nice features. However, you should check around. I have bought some of my controllers from Farmtek (a very large agricultural and greenhouse supply company) and my experience is that they also sell high quality equipment at good prices. In addition, they have a very good customer service department if you need advice. In comparing equipment, just be aware that some of the more industrial quality equipment doesn't come with an installed plug and would need to be hardwired into your setup.

I didn't see that it required electricity, lol! The very thing I'm trying to avoid needing. So, I found this one that it battery-operated. This seems to be the hard thing: Finding a battery-operated one that allows you to use it as often as I need and comes with everything you need. I looked at Farmtek and didn't really see what I needed there. Maybe I'm looking at the wrong stuff. Here's what I've found and am thinking I'll go with this unless I find something very similar that has all the features for cheaper in the next couple of days. I have found some similar, but they don't hook up the way I need them to. http://www.charleysgreenhouse.com/3345-Misting-Timer---Valve.htm

That looks good, too, but you might want to consider other sources as Charley's can be expensive. Check out the link below (bottom of the page)...I think it's the same thing, but cheaper...

Here is a link that might be useful: Timer

Stress and Kudzu are both giving you good advice.

Running utility lines may not be the most fun part of setting up a greenhouse but they are nevertheless necessary, for the reasons already noted here.

However, even the heavy cable specifically rated and labeled for outdoor, underground installation is not very pricey, nor does it need to be laid very deep; just enough to prevent frost heave (if any at your location) from lifting it, or having it accidentially disturbed when digging for gardening.

Don't go to the effort for any less than 30 amp. service and when you get the line under the edge of the foundation and up, into the GH, install a small circuit breaker in a weatherproof box. Then, GFIC outlets can be added where you need them. Use only a line with a ground wire and run it to a ground stake set outside the GH.

The extra work and relatively small cost of the materials will pay back in more than just safety.

Battery power is wonderful as a stand-by in case of an electrical outtage, but any appliance that must run continually, even if set to do so intermittantly, can be both an expensive and unreliable PITA when the batteries start to go.

I have 2 nelson Model 5945 timers, they are batterie operated. Have had one for 5 yrs and still is working well.They are installed with PVC pipe and misters. Have electrical run to greenhouse but had these timers before I run electric. And still using them.

Thank you all again for being so helpful! Please bear with me as I try to figure out what I need!

funnylady -- did you have problems with the LCD screen on your nelson 5945? I looked this model up and with the misting feature, it seems that it would work wonderfully 20 seconds on, 5 minutes off. I looked at reviews and almost hands down people say the LCD has stopped working. The timer works well still, but useless not being able to adjust it anymore.

kudzu, thank you for the link. It does look like the exact same thing, with the exception of the one you giving me being able to use 1-second increments and the Charley's is 5-seconds. Also, the Charley's has a valve connected to it. The one from Mr. Drip does not. I think I would be able to still buy this one much cheaper through Mr. Drip along with the valve but I'm not too sure what I need in the way of a valve since the one I have now is an all-in-one package similar to the Nelson model.

Mr. Drip has valves available but I'm not sure if this is what I would need: http://www.mrdrip.com/sprinklervalves.htm. I was thinking that #57623 or #57100 may work?

I don't even know what I would do to set it up, though. Would I just screw the valve onto the faucet and then hook the solenoid from the timer into the valve?

Thank you for your patience with me and all of your help, everyone!

desertgreenhouse-
You should give Mr. Drip a call. The link I gave you says that a solenoid is included...I don't know if that means only the solenoid or if it is a whole valve, but you're right that you can probably save money on this by going with Mr. Drip.

Both of my misters are still working fine. One is over 5 yrs old and the other is about 4 yrs old. They have always worked well for me. I never found anything better for the money. And no need to change as long as these are still working OK. But I keep looking because I know I will need to replace them one of these days.

Thanks for letting me know! I guess you bought them early enough in production that the LCD problem wasn't an issue yet. I wish I could trust that I would get one and not have problems, but I think I'm going to go with one that people aren't complaining about, at least not that I know of!

I called Mr. Drip, kudzu, and they were helpful. They said I should go with the one above it that has the valve b/c it's the newer version and the one I was looking at has been discontinued and they only have one left in stock. For servicing reasons, I think I'm going to go with that one and get the two adapters to use for a garden hose and that should take care of my issue on which valve to buy.

I'll look around just a little more but I think this is the one I'm going with. I'll let you all know when I get whichever one I buy how it's working out.

Thanks again for all the great advice from everyone!