Retaining Installation Guide

Installing Retaining Edges

There are a few differences when installing FormBoss® steel garden edging profiles over 290mm high. It may take a bit more work than our general edging systems but looks fantastic once installed.

Retaining Edging Profiles: 290, 390, 580.


  • Raised planter beds in any shape you desire, or straight.
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  • many more…

Curving Profiles Over 290mm High:

You can actually shape our large edging profiles more aggressively than the lower heights without kinking the top lip. This is because the length of edging has significantly more steel, giving it a more rigid backbone. It can help to have a friend help shape the edging, especially with the last 20cm or so, it is quite hard to get a tight curve into the last little bit as there isn’t any leverage. You can always shape your edges, cut off the last little bit, and use it as a connector if you find you can’t get enough shape into the last 20cm.

Producing Corners & Angles:

Corner-piece It can be quite difficult to produce angles on site with these larger profiles, as they are significantly stronger. We highly recommend that you purchase a pre-made corner piece to keep the installation as simple as possible.

If you do need to produce an angle on site it can be achieved by clamping a piece of timber to the edging exactly where you want your angle, you’ll also need to fix the body of the edging onto a surface (such as a strong bench) with a clamp. Now lever the edging up as far as you can, it can be handy having a friend since it is so strong. If you give the angled area a few whacks with a rubber mallet the angle will tighten.


The standard ‘triangle’ taped stakes are not strong enough to support these profiles. This is why we’ve developed our ‘L’ profiled angled stakes, they still slot up under the lip of edging, but are much stronger.

Galvanized Angled Stake They’re available in a range of different lengths to suit your project, and can be easily cut down to size if they are too long. It is highly recommended that you use a rubber mallet to knock the stakes in instead of any metal hammers as they will dent the steel. You will need to use two self tapping screws per angled stake as opposed to the usual one.


Connect your retaining edges in the same way you usually would, although you’ll need to insert two screws either side of the connector as opposed to the usual one. Clamping the edging whilst putting your screws in becomes a bit more important to ensure it doesn’t move whilst screwing.

The 580mm high edging can bow in the belly slightly since the profile is so high and because of the steels flexibility. Instead of inserting extra screws which can look unappealing, try popping in a couple pop rivets half way up your profile for a nice clean finish.


There are multiple methods of increasing the life of your edging systems, it is most important that you make an effort to improve the drainage and water penetrability to the largest profile heights, as they will have the most water build up. You can void your 10 year structural warranty if you ignore this (click here for t’s and c’s). Click here to see our preservation page.

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Greenlines Gardenware Pty Ltd, FormBoss® Australia HQ (VIC)

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