I don't know enough about your project to answer your question, but I'm going to guess that if I did, the answer would be "ABSOLUTELY NOT." What the heck are you trying to build? Wind may play an important part. 4" x 4"s are relatively heavy compared to any pot filled with whatever. Back up and explain the overall objective of what you're trying to do.

Added in editing: Ok. Scratch that. I see that your overall objective is contained in the title of the thread (which I obviously glossed right past.) Unless the pergola is for a doll named Barbie and her friend, Ken, then ditch this idea. There is no way that filled pots can hold timber tall enough for a human to walk under (unless the pots are 5 feet high and wide and the pergola covers a space no more than 5' x 5' ... and is probably indoors. It would not hold up against the wind.

But why not learn how to dig a post hole and mix a bag of concrete and set the post in that? It's a relatively easy, painless thing to do.

This post was edited by Yardvaark on Sun, May 5, 13 at 14:06

I can tell by the replies that I wasn't clear enough as to my intentions. These posts would be absolutely secured to the ground as well. I am using the pots as ornamental as well as filling them with cement to add weight and more stability.

My main concern is the cement IN the pot as I am concerned that it could possibly crack the pot. I want to make sure that this doesn't happen. Thanks again for your input.

Can you post an illustration of your proposed post to base connection then? Because a) how are you attaching a post to the footer through a pot? and b) if you have a proper footer attachment there's no reason to put concrete in the pots. Concrete's not going to be any better for the longevity of the post than potting mix.

Why not just set the pretty pots in front of the post, and fill the bottom 2/3 with rock if you want them to be really heavy?

Give me a day to draw up what I'm proposing... However ill be using a an anchoring system that will go into the base of the pole and down into the cement, then I will be pouring the cement into pot. The anchoring system should be sufficient, however we have been known to have heavy winds in our area and more is better than less during hurricane season.

As for putting the pots in front, I want the effect of the plant surrounding the pole completely.

Thanks again for the replies!

Pots full of concrete would be ugly.
No plants will grow on top of a pot full of concrete.
There's zero drainage and even if you did manage to drill enough drainage holes without shattering the pot the concrete leaches so badly that the pH would skyrocket. The pots would also heat up to a horrific degree making this environment inhospitable to plants in several ways.

And then as you water the plants ten times a day to try and keep the roots cool the patio surface below the pots will stain with algae and other soil schmutz and you will have no conceivable way to move the pots and clean the patio.
More ugliness.

Do the support structure separately from ornamental pots.
There is a reason people do not do this.
Several reasons.

Will, think you should ask what code is in Orange County. Can't figure out what in the world you're thinking here. Will wait for your explanation when you get it posted.

I have checked with Orange County and the method I am using to put the structure into the ground on one side and then attaching the beams to the other with the pots is to code.

As for the uninformed and rude post above yours Rosie, I'm not even going to acknowledge that person only to say, I saw this exact concept in Sicily when I stayed there for a summer with a family. They did exactly what I'm trying and never had any of the supposed issues that was voiced so ignorantly by cearbhaill. They used PvC piping and created a drain to the original hole in the pot and the structure was solid.

So again and back to the original question, will the cement cause cracking in the pot in Florida temperatures? I'm thinking no, however was curious if anyone had attempted it.

Thanks!

Not rude, just a curt style, lol.
If you had elaborated as to your inspiration and drainage plans you may have gotten a different response. To be honest the original post does read a little jerry-riggy.

I do believe that there are half pots commercially made to encircle a post and provide the effect you are after.

Thank you or clarifying and yes is was a bit abrupt, however that ls fine as I can be pretty curt myself. :-)

I will look to see if I can find those pot I are talking about... Because that would be perfect. Thanks!

I saw a similar project on DIY except they cut a square in the bottoms of the heavy decorative pots with a masonry saw and slipped them over the secured posts from the top (it took 3 strong men on ladders to lift them that high). There was no cement used but the pots completely surrounded the support posts and vines were planted in them. Nice effect.

I found a different take on that theme at HGTV and it actually sounds a bit more like what you are planning. The pot is secured to the post but not the patio. The difference is using concrete chunks so there would be proper drainage for the plants.

Here is a link that might be useful: Build a Pergola For a Deck or Patio

pkponder - that link is what I was picturing from the OP's description. Maybe it's because I've looked at a lot of leaning, twisting, and/or racking pergola structures in the past several years but I'm just not seeing resistance to lateral movement. If you have to periodically push your pergola back upright and re-tighten the carriage bolts, your design sucks, and that link has that written all over it.

Whatever, I've also read online articles on deckbuilding stating to use 2x4 joists and 4x4 support posts. My errors and omissions premiums don't go up when someone's DIY project falls over.

A fault of the original question is that there is not a good description of the overall intended purpose, or details that explain completely what is proposed. If it is anything like as shown in the link provided by pkponder, I think there is no way that such a structure would withstand the forces of wind. I didn't read every word of the article, but I got the impression that the posts do not penetrate and continue through the planter and into the ground where they are anchored by concrete. If that's the case, it will not survive. I'm with Marcinde regarding the lateral forces. This structure (the one in the article) is not strong.

But just on the idea of: will concrete crack the pots? I doubt it ... as long as there is not lateral force applied to a wood member (like a post) which might be imbedded into the concrete.

Not that I feel the need to state my experience in building pergolas, I will say that with all of the structures I have built, none have been rikity or weak. This one also will be able to withstand hurricane winds as have my other three on my property. One of which has a hand built wooden carriage gate 8' tall x 10' wide suspended from it. The last one, a Lowes special, was ripped off of it metal hinges from a previous storm.

Opinions of sturdiness and looks, though appreciated are not necessary. The one I need (whether the cement will crack a ceramic or clay pot is my concern), and I appreciate you answering that for me yaardvark. Though I do like the idea of removing the bottom of the pot which I will look into and may add this into the design. My only concern with that would be the obvious of the pots weakened state. Will the cutting create any structural flaws etc.

also, i assure you... how the actual 4x4 beams are attached to the ground will be above and beyond code, as I am not a fan of things falling apart.

Thanks again!

If you say you will build it awesome strong, WillCarpenter, we believe you. But from your cryptic description along the way, it was never made apparent that you would, or how you would do it, or that you had any experience in doing so. So that's the reason for the crowd of doubting Thomas's.

I think that cutting a ceramic container with a wet diamond blade is your best bet for keeping it structurally sound. It probably wouldn't need to be cut wet, but wet makes for the smoothest cutting.

I know what you are saying. However, I wasn't looking for any input besides the original querie of cement possibly cracking the pot! Lol... But am still glad I did get the input I did; simply because it has given me some good ideas. :-)

I will look to see if I can find what you are talking about, that will do the cut I need. Thanks!

Good luck. When you get done you might post a picture. I'm sure everyone wants to see!

Yeah put me in the spot light... ! Lol

I guess I won't have much of a choice but to do that.

Where I live (Sacramento, CA) we have a cinder brick retaining wall that has a fence on top. Part of it was built by one company, but there were some problems etc, so I hired a different company to do the rest.

For the part built by the first company, they used wooden posts set into concrete through the retaining blocks. The second used metal posts.

The cinder blocks that have wooden posts set in concrete -- the concrete is IN the block with a wooden post (kind of like how you describe the concrete in pots, then with the post in it), all those cinder blocks have a crack through them :-( I think that the post swelled/shrunk enough to crack the block.

Why wouldn't something like this happen with wooden posts set into cement in a pot?

Melle that is where my concern lies. With water soaking into the wood. Even though I plan on weather proofing the wood, also purchased weather treated and plan to rubberize the 4x4 I am still concerned. Granted Sacramento is a bit colder than Florida, that is a very good point you made. Thank u

I found this question by googeling the same question!! I want to put cement in a pot to hold a heavy iron cross that I can’t put outside. We also live in Florida and I want it in my Lanai without worrying about it falling over. I know I could use a plastic bucket but that is not the effect I’m looking for. Thoughts????

I'll put my 2 cents in, but in general, when asking a new question about another project it's always better to start a new thread.

There's no reason you couldn't sink a heavy iron cross in concrete in a pot. You'd want to make sure that the pot is large enough to hold enough concrete so the cross ends up being stable and not knocked over too easily.