Installing lamp posts

I bought two lamp posts at Lowes and I want to install them in our back yard flower garden. The lamp posts are about 6 feet tall and made of some sort of very light metal. I'd estimate they weigh no more than 20 or 30 pounds each - maybe even less. The bases of them are about a foot in diameter with three semetrically placed bolt holes for mounting. The ground where I want to put them is mulch covered soil.
I was thinking about maybe buying a wooden post that was wide enough in diameter to bolt the lamp post directly into the wooden post and cutting off about 2 or 3 feet of it and using post hole diggers to dig a hole such that the wooden post is flush with the ground, then bolting the lamp post directly into the wooden post.
That was just one thought I had. I guess concrete is another idea, but how do I do that? How deep do I dig the hole for the concrete? Do I dig it deep and narrow like a post hole or wide and relatively shallow? And do I make it cubical or bowl shaped? And do I need to line it with something or just poor the concrete right in? And what is the best way to ensure that the concrete is level before letting it dry?
I'm really clueless as to the right way to do this job. I can tell you that power isn't going to be a problem, it's already run and terminated very near the location. I just don't know how to get the lamp posts to stand up, permanently, in the dirt.
Obviously I'm not very knowledgable about matters of home improvement. Any advice would be appreciated.
Thanks in advance.
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You should have received mounting bolts with the posts. These bolts are about a foot long, threaded on one end and bent at a right angle at the other. There should also have been a template for the bolt mounting positions. You would run a PVC conduit with your cable in it, to the center of a pit, the PVC should have a 90 degree elbow facing up, so the cable is not in the concrete, only the PVC. Fill the pit with concrete flush with the ground surface, and push the mounting bolts into the concrete, leaving about two inches sticking out. Be sure the bolts are in the exact pattern of the template and stay that way until the concrete sets. Once dry, slip post over PVC allowing cable to be threaded through post and out the top. Bolt post to threaded studs using washers to level

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Thank you for the advice. I will follow it. How should I dig the hole for the concrete? Should it be a narrow and deep hole? What dimensions should I dig the hole?
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I don't think it needs to be more than 18 inches deep and large enough that the mounting bolts are not closer than about 2 inches from the edge

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Make sure you do not NICK the insulation on the wire. If you do and the wire gets wet when it rains, it will trip the ground fault interrupter.
Mark
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wrote:

Did you happen to read the instructions? I would think some suggestions would come with the lamps.
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Suggestions do come for mounting the lamp into various surfaces, none of which are dirt. So I need to get one of those surfaces into the dirt. The concensus seems to be concrete.
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I would have made a comment but I'm confused about what type of lamp you have. The ones I'm familiar with are 3 or 4 inch tubes meant to be buried 2 or 3 feet down.
For that type of lamp you have 2 choices, just put it in the bare dirt or dig a hole about 6 inches across and pour in concrete.
I'm 30 years in the same house and I've replaced the lamp post twice. The first one was in concrete. It was a royal pain to get out.
Since then I've just stuck them in the dirt. A whole lot easier to get out that way.
I've had them lean slightly after long winter. As long as the soil is saturated, you just push it back upright.
For lamps, I don't think concrete is the right choice, just stick it in the ground.
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Thanks for all the advice. Dan, I don't think the lamp post is meant to be buried directly into the dirt, because it has three bolt holes at the bottom. It does have a little leaflet that, I suppose, is meant to pass as instructions, but they were obviously intended for someone with at least an inkling of what they were doing, because they didn't mean a whole lot to me until I read RBM's post. The equipment that comes with the lamp is pretty much what he describes... three bolts with 90 degree elbows near their end and a template. The instructions show a cutaway view of what looks to be a slab of concrete with a PVC pipe sticking through it and the bolts sticking out of the top of it. I think RBM pretty much described in words what the picture intends for me to do, so I think that is the advice I will follow.
Thanks again all. Wish me luck :)
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