We plan to install an outdoor lamp post. We want to figure out the best way to use smart controls (edited to add: we’re in the US).
– We do not yet have any smarthub so we’re open to all options, though we have ring cameras and a Nexus controlled thermostat (but are fine with a new hub and third app).
– We want it to go on dusk to dawn (via sensor on lamp) and use smart controls to turn it temporarily off if we’re outside, with the option of using smart controls programming to turn it off at (say) 2-10a.m. so that it’s not on all night but will come in a at dusk again the next day.
– We think we want a wired wall mounted controller (exterior panel is very close to the wireless router, so signal is good) instead of a switch but I’m interested in hearing from folks who think we’ll regret not having a physical switch (which means we could use a smart toggle switch). We’d prefer no switch just because of the additional wiring required.
– Is a dimmable lamp post an option and would we be able to dim it from whatever controller app we’d use?
– Are there any types of lamp posts that we should get or avoid getting if we wanted to use smart controls?
– What else do we need to consider with an outdoor lamp post? I’m case it’s relevant it will be ~120 ft from the house, and we’ll be running wire down there for a receptacle as well, and pipes for an outdoor spigot.
Just to confirm, what country are you in? The device selection does vary somewhat. 
Also, when you say “Lampost“ three other questions come immediately to mind.
One) how tall does it need to be?
Two) how bright does it need to be (in lumens)?
Three) how big of an area needs to be illuminated?
Sorry! USA. I’ll edit original post.
Height, lumens and area - still determining that. We’d sacrifice brightness and area for control of needed, so if we can only do some things if the lamp is under or over some s pecs, we want t o factor that in. FYI post will provide light for a path going to a boat dock.
Also, how much humidity do you typically get, including rain/snow? The reason that I ask is that this can disperse signal, making it difficult to get signal out to the lamp post. This means that a device that might work well in Arizona might not work at all in Florida. 
OK, path going to a boat dock has a number of related to safety issues, so you’re probably going to want it pretty bright. I would probably put in a conventional light with a conventional switch and then just make the switch smart. I understand that will mean some additional wiring, but I think it will be worth it.
If it’s a lot easier, it would be OK to use a power post in the yard with a smart relay on that and then put a second smart switch inside the house to communicate wirelessly with the one in the yard. That’s what some people do for pond pumps, for example.
I can’t imagine that we’d be able to get a signal all the way out to the lamp post no matter what the weather, as it will be too far away, which is why we are looking at either a wired smart switch or smart toggle light switch at the house. Or am I misunderstanding your question?
It’s not too far away for either Z wave plus or Wi-Fi. You can test that with Wi-Fi pretty simply just by walking out there with your phone and seeing if you still get Wi-Fi signal from the house.
But in any case,
What else do we need to consider with an outdoor lamp post? I’m case it’s relevant it will be ~120 ft from the house, and we’ll be running wire down there for a receptacle as well
If you’re saying with the above that you are intending to have the lamp post to be a regular dumb lamp post and to control it with a smart switch inside the house, that is indeed the approach I would recommend as it will give you the most options in terms of brightness and area covered. 
Great questions and feedback, thanks!
There’s not as much of a safety issue as it sounds - the path is not steep (in fact barely any slope before the post location), and there’s no place on the path where one could trip into the water or anything. While we want the lighting to help illuminate the path, we don’t use the boat at night, and the lamp is more to illuminate a seating area that we plan to create down there. But what I’m seeing indicates that lamp posts are typically 120-180 lumens, so at the mid to high end of that range should be fine.
I’m not sure we mean the same thing by “lamp post“ then as 120 lm is quite dim, The equivalent of about a 13 W night light, and is typically used for path lighting of the following type:
You usually need four or five of these at least along the path, and they aren’t the kind of thing you would use to aluminate a seating area.
In contrast, lighting for a driveway is typically around 1200-1800 lm. (This picture is of a fixture with two 600 lm bulbs)
I’m aware there’s a Home Depot lighting FAQ that says lamp posts are typically 120 to 180 lm, but they are talking about the kind of path lights like in the first picture above.
If you Look at their full-size lamp posts, which are more typically the ones people would put next to a seating area, those have 100 W equivalent lights which are over 800 lm.
Yes, smart light switch or smart switch. This is one of the things I was looking at (link below). We definitely don’t need 40amp but I can’t find anything that’s direct wired that’s 20amp, so I’m presuming we can put just a single 120v circuit on it though it supports two. I know that there are potential advantages of just doing the extra runs to install a smart toggle switch, but honestly right now we’re even factoring in that a light switch would require someone to do indoor work, and we’d like to keep this as an outdoor-only project so that we can do it before we’re out of isolation – not only because we’re both medically very high risk and would have to put off indoor work until the risk has subsided (we’re still trending upwards around here) but we’re also looking for outdoor projects to keep some of our preferred contractors working during this time. This wasn’t a high priority project until our contractors had to stop doing all indoor work.
LOL I thought that seemed awfully dim for what I remembered is used by a lamp post but hey, if you read it on the Internet then it’s true, right?
So I definitely want one on the much lower end of the brightness spectrum - and I’d still love to find out if dimming is an option. I’m guessing not but I believe it never hurts to ask or research. 
I understand.
Sorry, I’m fading right now so hopefully other people will chime in. I understand what you’re saying, that you want to put a smart switch/relay outdoors that is wired to the lamp post and you want to have a battery operated wall switch or controller inside the house so you don’t have to have the contractors there. That should be very doable.
I’m just going to tag a couple of people who might have some more ideas.
One last thought: take a look at the ring lighting devices, they have a lot of options now and they work very well. I don’t know if they meet your aesthetics, though. But they have a good range and good controls, including dimming.
If I recall correctly, @jkp has a bunch of these.
They even have a new floodlight bulb you can install in a regular fixture. So lots of options.
Or a wired outdoor smart controller one the one I linked to before. Definitely looking for all options. Thanks for your help.
If it’s just one lamp post and if it accepts regular size bulbs, a smart bulb may just be the easiest option. It will give you the ability to dim the light and You could try a ZigBee, Z-Wave, or wifi one to see which communicates best with the hub. Then you can have any Z-Wave switch or remote control it for on/off and dimming (you’ll need a Z-Wave dimmer or one that supports scenes to enable remote dimming). This is the option easiest to wire and harder to program because of the rules you’d need to establish to sync the bulb and the switch / remote control.
The option easiest to program would require direct wiring to a Z-Wave switch indoors. No additional programming would be needed then.
Both options would allow you to control the light using your smart speaker if it’s connected to SmartThings.
I finally measured and verified that the distance will preclude the use of a smartbulb - signal is only -75 right now and it’s a nice clear day. Signal strength where I’d mount an exterior direct wire switch is close to -50 which is excellent and reliable.