Can You Plant Pots on Composite Decking?

Whether you are creating outdoor space for relaxing, cooking and dining, or other outdoor activities, composite decking can be a great option. Composite decking has a natural visual appeal, but you’ll still want to personalize and give your deck an aesthetic look with furniture and floral decorations. But can you plant pots on composite decking?

You can plant pots on composite decking because this type of decking has better resistance to stains and damage from moisture and dirt from potted plants. However, dirt, moisture, and debris from plant pots on composite decking left unattended for a long time can cause damage and should be avoided.

This article will go over the use of plant pots on composite decking by defining composite decking and explaining why using plant pots on composite decking is advisable. The article will also tell you if there are any risks with plant pots on composite decking and how to can counter those risks. 

Why You Can Plant Pots on Composite Decking

Composite decking has many economic and aesthetic benefits. For this reason, it’s becoming more and more appealing to homeowners and is increasing in popularity. 

Here are a few of the general benefits of using composite decking:

  • Composite decking has lower thermal expansion because of the wood-plastic combination.
  • Composite decking is highly durable and has a longer lifespan than wood decking. The American composite decking manufacturer, Trex, gives composite decking a lifespan of 25–30 years.
  • Composite decking retains its color and maintains its esthetic quality for longer.
  • Composite decking has a higher resistance to slip.
  • Composite decking is low maintenance and easy to care for compared to wood.
  • Composite decking has varied quality options, offering the consumer competitive, affordable prices compared to traditional wood decking. 

While it is worth appreciating the general benefits of composite decking, not all of these benefits directly support the use of plant pots on composite decking. So, let’s now focus on those benefits that support using plant pots on composite decking.

Below are the 3 key reasons you can use plant pots on composite decking:

1. Composite Decking Has Better Moisture Resistance Than Wood

Whether it’s the water that falls on your deck when you water your plants or the moisture from a plant pot sitting in the same spot on the deck for weeks, composite decking offers better resistance to moisture and dampness. This is thanks to the plastic content in the decking boards, which also gives good resistance to rot.

In addition, composite decking does not have the high moisture absorption rate of natural wood. As a result, placing plant pots on composite decking does not easily cause warping, fading, or staining.

2. Composite Decking Won’t Spoil With Mold and Mildew

The humidity in potted plants is a favorable environment for mold and mildew growth. Left for days on wood, mold, and mildew will eat into the wood and cause damage. However, this is not the case with composite decking. The mildew or mold can sit on decking boards for a while without leaving a permanent mark. 

Besides, you can easily get rid of mold and mildew on composite decking by washing the decking with water and mild dish soap and giving it a thorough rinse. And washing won’t cause any wear on the decking boards.

3. Composite Decking Won’t Stain Easily With Tannins

Tannins are phenolic compounds in plants associated with the captivating colors of plant leaves and flowers. They are also the cause of the astringent taste in some fruits. Tannins are found in plant barks, wood, roots, galls, leaves, and seeds or flower buds. 

Left on wooden decking, plant leaves and flower buds from potted plants can leave tannin stains. This will not happen so easily on composite decking, especially if it is capped composite decking with an additional plastic overlay.

Of course, you don’t have to consciously put your composite decking to the tannin-staining test by leaving leaves and flower buds scattered all over your deck. Getting rid of them by regular sweeping will eliminate any risks of staining, especially in the rainy season when the leaves and petals remain wet.

Despite the above supporting reasons, there are also risks associated with using plant pots on composite decking.

Risks of Planting Pots on Composite Decking

They say perfect is not of this world. So, using plant pots on composite decking will not be the exception and has its own risks.

Even with its low risk for rot, staining, mold, and mildew, composite decking can be prone to these same issues when:

  • There is inadequate airflow between plant pots.
  • Dirt and debris are left on composite decking for long periods.
  • Plant pots are left in the same spot for months.
  • The composite decking is regularly exposed to water without the conditions for fast draining or drying.
  • You have an old-generation version of uncapped composite decking. Older versions of uncapped composite decking have exposed wood fibers, making them more vulnerable to fading, staining, mold, and mildew.

So, how do you manage the risks of plant pots on composite decking? Our next section has the best tips on how to do that.

Countering the Risks of Plant Pots on Composite Decking

Considering the risks of plant pots on composite decking, it is important that your use of plant pots and the care and maintenance that you give your composite decking is good enough to keep these risks at bay.

Here are 3 tips for countering the risk of plant pots on composite decking:

1. Go for Quality Composite Decking Boards

While lower quality, uncapped composite decking boards may come cheaper, the exposed wood fibers make the decking more prone to moisture damage. Avoid paying the consequences of “cheap is costly” and opt for the more moisture-protected and hard-to-stain capped composite decking.

2. Move Plant Pots on Composite Decking Regularly

Moving plant pots now and then is good gardening practice. This may not just give your plant a new and better spot, but it will also spare the previous spot from damage by plant moisture in the long run. 

Moving your plant pots should be more regular in rainy seasons when water tends to stand on the deck or beneath the plant pot longer. The damp winter weather should also encourage you to move your potted plants regularly, especially if the planters are made of concrete, terra cotta, or pottery.

2. Elevate Plant Pots With Planter Feet or Hangers

Using hangers for potted plants or flowers will keep them off the surface of your composite decking. That will save your deck from rings or stains from flower pots sitting on the surface for long months.

If you have larger potted plants that are difficult to lift and move, using planters with feet will keep the pots off the ground and, therefore, save the decking from plant pot stains.

3. Don’t Overwater Potted Plants on Composite Decking

Especially if you have plants that require frequent watering, it is important that you give the plant the right amount of water each time. 

Whether your plant sits on a platter on the decking, is on a pot with feet, or is hanging above the deck, water that’s consistently dripping from an overwatered plant will create standing water on composite decking. This standing water will cause staining or other forms of damage with time.

4. Clear Dirt and Debris From Potted Plants Regularly

Even though it is more resistant to debris and dirt staining than wood, composite decking can show stains and damage if debris and dirt from potted plants stay on the decking for long periods.

As such, you should regularly sweep and collect any fallen leaves, flower petals, and plant pods from your composite decking to prevent them from leaving behind tannin stains. 

You should also wash your composite decking with water and mild kitchen soap any time you have dirt stuck to the decking. Ensure you only use a soft brush to scrub and rinse off the soap thoroughly. 

Note that some manufacturers, such as the earlier mentioned Trex, will consider your stain warranty void if the damage on composite decking is caused by improper handling and neglect. And leaving plant debris on composite decking could very well count as neglect.

What Is Composite Decking?

The term composite refers to something made of different parts or substances merged or amalgamated. In this light, composite decking is produced by combining natural wood fibers with recycled or virgin plastic and chemical additives that serve as bonding agents.

To create composite decking boards, the mixture of wood fibers, plastic, and bonding agents is heated and shaped into longboards before being left to cool. The resulting composite decking boards have high durability, require less maintenance than their wood equivalents, and have better aesthetic value than their plastic alternatives.

It’s because of its many benefits that American homeowners are increasingly opting for composite decking in place of traditional wood decking. Statistics show that the composite decking and railing market was estimated at one billion US dollars last year (2021), with the figure expected to hit 6.5 billion US dollars by 2026.

The benefits of composite decking are also the same reasons you can plant pots on your deck. Let’s explore those benefits in the next section.

The Bottom Line

You can plant pots on composite decking without adverse risks for stains, mold, mildew from plant moisture, fallen plant leaves, flower petals, or dirt from watering the plant. 

However, leaving dirt and moisture around plant pots on composite decking for long periods can still cause damage.

Ensure you clean any debris and dirt from plants on composite decking and facilitate good airflow between plants. Also, lift plants off the decking by hanging them or using plant pot feet to prevent moisture and dirt from damaging the decking.

Alexander Picot

Alexander Picot is the principal creator of TheGrowingLeaf.com, a website dedicated to gardening tips. Inspired by his mother’s love of gardening, Alex has a passion for taking care of plants and turning backyards into feel-good places and loves to share his experience with the rest of the world.

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