Choosing the Right Planter Material for Campus Projects

A successful project has three main characteristics. First, the sourced product arrives as specified and on time. Second, the individuals  involved complete the requested services on time. Finally, the completed project meets the need that was originally specified.

Many of these projects require planters that are sourced, delivered, and planted. If planters are a part of your final design, decisions such as color, planned location of the planter, and, most importantly, the material for the planter will need to be made.

What the Material Dictates

The material you choose will dictate lead-time, durability, personalization (as well as customization) and budget. It is important to consider material along with color, shape, and location, as it will have a direct effect on the success of the proposed project.

It is for those aforementioned reasons that I have examined four different materials that are most commonly requested for planters and explained the composition, cost, lead time, and optimal use of the material to help make the decision-making process easier for you.

Aluminum Planters


Aluminum is a chemical element found in the earth’s crust. Although aluminum is one of the earth’s most abundant elements, it is never found alone in nature. Therefore, aluminum is extracted from the substances with which it is found.

There are several different types of aluminum that can be sourced for a planter, but I feel one of the best materials and the one to ask for is 5052 marine grade aluminum alloy. This type of aluminum alloy is also commonly used in shipbuilding and aircraft fabrication. Using this type of marine grade corrosive resistant aluminum ensures that your planters can withstand the elements and will need little to no maintenance.

Production of Aluminum Planters

When aluminum sheets are used to make planters, a shear and brake machine is utilized to form the desired pieces that create the shape of the planter. Once the shaping is complete, the planter can be spot welded, which is not watertight, or fuse welded on the outside, which is watertight.

Most fabricators will then sand the welds so that all the edges are smooth, and the welding beads are invisible. Finally, the aluminum is powder-coated. A powder-coated finish is done by first using a dry powder, then that powder is cured under heat. The curing process creates a hard, long-lasting finish.

For planters that are large enough to accommodate small ornamental trees or large shrubs, make sure to ask the supplier if reinforcements will be added, as reinforcements ensure that the planter is structurally adequate.

Benefit of Aluminum Planters

The benefit of using aluminum for a planter is that it does not rust and is powder-coated for durability. Powder-coating the planter ensures durability because commercial powder-coating formulations have characteristics that enable the planter to withstand UV rays, temperature changes, and other severe weather conditions.

In addition to its durability, aluminum planters can be modified to add elements such as castors, lights, speakers, or even toe kicks, which create the illusion that the planter is floating. It is worth noting that aluminum is easily customizable and can be created into most geometric shapes with 90-degree corners.

A powder-coated aluminum planter is perfect for all interior or exterior applications, can be powder-coated with almost any color, and fabricated to a size that is big enough to hold an ornamental tree.

Withstanding Extreme Weather and High-Traffic Areas

Commercial grade powder-coated aluminum planters are perfect for a project that requires a low-maintenance, lightweight metal planter and that can withstand extreme weather conditions as well as high-traffic areas.

Aluminum planters are available in a variety of sizes, shapes, and configurations. Although powder-coated aluminum planters are typically more expensive than fiberglass, they will last longer than a fiberglass planter.

This planter material works well in all applications but especially works well on rooftops or places where the overall weight of the planter, plant, and filler is a consideration.

Fiberglass Planters


Appropriately referred to as glass fiber, fiberglass is a composite material made of molten glass that has been forced through small holes and then woven into fibers. Fiberglass has several applications such as insulation in your ceiling or, in our case, it is layered with resin to make a planter.

Production of Fiberglass Planters

A mold (also known as a plug) of the desired shape and size of the planter is created using wood or plastic. Then, the fiberglass material is hand layered; once the planter is dry, it is removed from the mold or plug and then continually sanded until all the imperfections are gone. The planter is painted with a primer and then with your choice of color. It is best to have a paint that is considered commercial grade.

For larger planters, internal reinforcing is added as part of the integral structure and layered with the fiberglass during manufacturing to ensure the planters are structurally adequate for a small ornamental tree or larger plant.

Benefit of Fiberglass

The benefit of using fiberglass planters is that they are lightweight and-depending on paint grades-resistant to corrosion, frost, and UV rays. Most fiberglass planters also require very little maintenance and do not need to be taken indoors during the winter months.

Like powder-coated aluminum, fiberglass is a great material for planters, especially when total weight is a factor for rooftop projects or high-rise balconies.

Lightweight, Low-Maintenance, and Budget Friendly

Fiberglass will fit your material need for your planters if you are requiring a planter to be lightweight, low-maintenance, and budget-friendly.

Fiberglass can be painted in almost any color. It is important to note that it is challenging to customize the shape of a fiberglass planter. To customize a fiberglass planter, the manufacturer needs to first make a new mold before creating the final product. This makes the wait time for the planter much longer (up to 14 to 16 weeks) than for that of a customized, powder-coated aluminum planter.

With that said, if there is no time constraint and the desired shape cannot be done in metal, fiberglass is the material of choice.

Brushed Stainless Steel Planters


Stainless steel is a type of alloy of iron that has a minimum of 10.5% chromium. Chromium creates a thin layer of oxide on the surface of the steel that makes this steel tarnish and rust resistant.

Production of Brushed Stainless Steel

First, a shear and brake machine shapes sheets of stainless steel. The resulting piece is then, in most circumstances, fuse welded to be watertight and then the welds are ground and dressed to look like brushed stainless steel.

The dressing is done by hand and with abrasives, which is time-consuming, but very appealing if an ultra-modern design is desired.

Benefit of Stainless Steel

The benefit of using stainless steel planters is that this material is naturally resistant to corrosion, chemical damage, heat damage, and can withstand a variety of weather conditions.

Modern Finish for Indoor and Outdoor

Stainless steel will fit your material need if you are looking for a modern finish for both indoor and outdoor. Stainless steel planters are heavier than both fiberglass and powder-coated aluminum planters and can be up to two to three times more expensive than aluminum.

If the high shine of stainless steel is desired, but the cost of using stainless is out of your budget, then certain colors of powder-coated aluminum can be used to emulate the desired look.

COR-TEN Weathering Steel Planters


COR-TEN is the United States Steel trademark name for weathering steel. COR-TEN is a group of steel alloys. The name COR-TEN comes from a combination of two of its essential properties: corrosion resistance (COR) and tensile strength (TEN).

Production of COR-TEN

A shear and break machine cuts sheets of COR-TEN weathering steel into the desired shape. If the planter does not need to be watertight, the cut sheets are then spot welded. If the planter needs to be watertight, it can be fuse welded instead.

Once the planter is shaped and welded, the planter is complete, as there is no required finishing step for weathering steel. When you first receive the planter, it will look like raw metal and will need to be installed in an outdoor location to patina to an orange-brown color (patina is a key final process for COR-TEN steel).

If requested, the planter can be pre-treated with a chemical before shipment to speed up the patina process.

Benefit of Weathering Steel

One important characteristic of COR-TEN weathering steel is that it patinas beautifully after exposure to the climate. Because the outdoor elements are essential to the patina process, COR-TEN planters are only recommended for outdoor use.

This patina is key because it protects the planter from further corrosion, therefore making weathering steel planters a long-lasting option.

Before purchasing planters made from COR-TEN weathering steel, one should understand that as the planter patinas, it will most likely bleed onto the supporting surface. COR-TEN planters fit well in an industrial design that requires elements with an organic feel.

A Modern Industrial Design

COR-TEN weathering steel will fit your planter material need if you are looking for a modern industrial design, don’t mind waiting for the material to patina, and the area the planter is sitting on can tolerate the metal bleeding.

Due to the cost of weathering steel, these planters are also more expensive than powder-coated aluminum planters, are substantially heavier than aluminum and fiberglass planters, and can take up to six to eight weeks for fabrication.

About the Author
Amy Gustafson is the Marketing Manager at Pure Modern; she can be reached at Please contact 1-800-563-0593 or visit if you have any questions.