I have yet to find any bracket that would fit my odd-width/depth aluminum rail top. I ended up using metal windowbox "hangers" (the hook-on type that take the 2ft long windowboxes), hanging them so the windowboxes would face the inside, and literally wiring the hanger hooks to the rail with some thick gauge copper wire. You can level the windowboxes with some blocks positioned between the hanger and the rail's fencing and/or vertical bars.

You might be able to rig up a windowbox support using some C-clamps (or equivalent) too.

Hey thanks for the tips.
I have seen those wide metal hangers. Your idea to put blocks wedged in there to hold them up is good. I kept picturing them hanging at bad angles. I have some plywood and was trying to figure out how I could build a secure shelf balanced on the railing, but have yet to come up with a fool proof plan . . .

You can use chain or rope to connect both the near and the far ends of the planter to the railing and keep it horizontal:

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To hold the planter firmly in place, I started by running a loop of heavy chain underneath the lip, making sure that it fit snugly. A small U-bolt goes through a hole in each corner of the planter and through a link in the heavy chain. These are connected by lighter chain to the balcony railing, and held in place there by U-bolts that are just wider than the railing. Adjust the chain lengths until all chains are taut and the planter is level. The materials are available at any hardware store, or buy stainless steel ones from a marine supply.

You can also bolt the planter through the bottom to a wooden beam or plank that braces it against the wall or railing:

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For best results use a wood such as cedar that won't rot. And of course, however you decide to do it, rig up your planter before you add soil or plants!

I too have 1 inch railings and have had a booger of a time trying to find brackets to fit.

I found an adjustable window box bracket that not only adjusts to fit the railing but to fit the bottom of the window box as well. I paid $2.00 a piece for them at Big Lots but can't find any anywhere on the internet (probably because they are so cheap). You may have to shop around locally (Wal-Mart, Big Lots, K-mart etc.) to find them.

{{gwi:594}}

Best Wishes
Amino-X

I've have the single pot version of that type of bracket. But unfortunately my rails are just bizarre because they are always like a 1/4" too thick or 1/4" too wide and that keeps a sliding clamp or hook from being secured on them properly. For some reason, my rails are non-standard and that's a pain.

I have the same problem with the new iron railings my landlord just installed. I found these, but haven't purchased them yet: http://www.windowbox.com/store/product/Brackets+[26]+other+Container+Accessories/Brackets+[26]+Hangers/W0314.html

Anyone have any reviews?

Check out this safety stripes -- http://www.windowbox.com/brackets-container-accessories/deck-rail-brackets/window-box-cable-ties.html

After scouring the entire internet several times I can report some dude in Canada selling products on eBay which for the style and price look better than anything else. http://www.ebay.com/itm/NEW-BALCONY-RAILING-FLOWER-WINDOW-BOX-GARDEN-PLANTS-BRACKETS-APARTMENT-CLAMPS-/181107564974?var=&hash=item2a2ada21ae He has a 100% approval rating. He does not show a package or give a brand name, but gives the country of manufacture as Canada, so perhaps he designs and manufactures these himself or obtains them from whoever does. Unless I receive serious advice against, I will probably order
these and can report on how well they work.

I found using the old wire hangers and a pair of pliers. It took two hangers. I found a design on eBay and copied the sizes. When making the crossbar, I added gorilla glue and wrapped the wire twice.