Planters are made of different materials, some of which are porous and absorb moisture, causing them to expand. Winter comes with extremely low temperatures, making the moisture in porous planters freeze up and the planter expand and possibly crack. Most types of planters are vulnerable to harsh weather and should not be left out in the winter.
Concrete planters are made of sturdy, long-lasting material and can safely be left out in the winter. However, concrete is also porous and will absorb moisture from winter snow. If the planters are not made with quality material, they will expand with moisture absorption and possibly crack.
This article explains the way concrete planters can resist the elements. I’ll give you some basic info on concrete planters and discuss their ability to withstand extreme winter temperatures. You’ll also find some tips on how you can keep your concrete planter free of damage when left out in the winter.
Concrete Planters: Overview and Characteristics
Concrete planters are heavy pots that are made with three primary ingredients: water, rock, and sand.
Concrete can be poured in liquid form into a mold to create concrete planters. While the mixture is still wet, another container is pressed into the wet concrete to produce the interior shape.
In its ordinary state, concrete makes planters with a light gray shade. However, concrete planters are actually very versatile, and can be painted with masonry paint to suit user preferences.
Concrete planters are only one option among many others, such as:
- Plastic
- Terracotta
- Ceramics
- Metal
- Wood
- Fiberglass
If you are choosing concrete planters over other planter types, it’s probably because of their many advantages.
Advantages: Durability, Weather Resistance, and More
Here’s a quick list of concrete planter pros:
1. Durable and Environmentally Friendly
Concrete planters are long-lasting. This also makes them environmentally friendly because they do not have to be replaced often like other materials such as plastic.
2. Weather Resistant
Concrete planters are heavy and can withstand the elements. They will not tip over in extreme conditions such as rain and windy weather. This also makes them ideal for windy balconies.
3. Acts as Plant Soil Insulation
The density of concrete planter walls preserves soil temperature and prevents it from fluctuating and causing damage to plants.
4. Good Porosity
Concrete is porous and allows good soil drainage. Good porosity controls over-watering and prevents root rot.
5. Suitable for Potted Trees and Shrubs
Since they are sturdy, long-lasting, and can withstand the elements, concrete planters can be created in larger sizes. Bigger concrete planters can hold large plants and shrubs and efficiently support their root growth. This protects the plant from root crowding and provides better moisture retention in the soil.
6. Damage Can Be Concealed
Since concrete planters have a coarse texture, minor damages can be easily concealed, unlike other planter materials like plastic and clay. Besides, cracks and breakages on a concrete planter can be easily repaired without needing to dispose of the planter.
If you would like to explore your options to keep your concrete planters from cracking, check out my article: How to Keep Your Concrete Planters from Cracking
7. Can Be Improved With a Waterproof Sealer
Since it is porous, concrete facilitates good soil drainage. This is good for planters that do not need much moisture and frequent watering. However, if you are putting a plant that requires more moisture into a concrete planter, you can reduce moisture loss using a waterproof concrete sealer.
The waterproof sealer is applied on the interior side of the planter to keep water in the soil. The sealer can also be applied on the exterior side of the planter to give a smooth and shiny finish. This helps the planter withstand discoloration.
The Rain Guard Water Sealer from Amazon.com is a good option. It does not alter the concrete planter’s natural look. It also withstands water and mineral damage well.
Drawbacks: Chemical Impact, Cracking, Discoloration, and Weight
However, concrete planters also have some drawbacks:
1. Concrete’s Chemicals Can Impact the Plants
The chemicals used to facilitate bonding in the concrete mixture can have a negative effect on plants. Cement has high lime content, which raises alkalinity levels. Highly alkaline soil is unhealthy for most plants.
2. Some Are Prone to Cracking
If poorly manufactured, the pores in a concrete planter can accumulate moisture in extreme winters. As a result, the concrete will expand, leading to cracks.
3. A Fading Natural Appearance
Concrete planters used outdoors will lose their natural appearance over time. This is especially true when concrete accumulates moss, salt, and lime deposits, causing discoloration on the surface.
4. Planter Weight
Concrete planters can be extremely heavy and hard to move, especially if they are large ones. This is one of the reasons moving them inside in the winter can be cumbersome, so most gardeners opt to leave them out over the winter season.
So, can concrete planters be left out in the winter? Let’s explore that in the next section.
Winter Weather Can Cause Cracks and Damage
Winter weather is characterized by snow and subzero cold temperatures. Such weather does not favor planters made of porous material because they accumulate moisture from the snow. These materials contract with low temperatures and expand with increased moisture. As such, they can end up cracking.
Since concrete is porous, planters made from this material can suck in moisture and crack. This will mostly happen if the planter has a thin wall and was not conditioned well when it was manufactured. If it’s not made well, it won’t last, but if it is thick and well-made, it should be just fine.
Poorly-made concrete planters left with soil will also retain more moisture from the soil and can expand when the soil expands. Newer concrete planters also tend to be more prone to cracks than older ones.
All this means that your concrete planter can crack if left out in the winter. As such, if you have smaller concrete planters that are easy to move, consider bringing them inside before winter sets in.
On the other hand, however, concrete is generally a sturdy material. When created with high-quality materials, concrete planters can withstand the extremes of winter and last for years. This means you can safely leave your concrete planter out in the winter.
That said, leaving your concrete planter out in the winter will require you to take certain measures. The measures will ensure the container remains safe and free of damage.
Tips for Preparing Concrete Planters for Winter
If you decide to leave concrete planters out in the winter, the following measures can be taken to keep away moisture and prevent cracking. Some measures will also cover the aesthetic aspect of concrete planters left out in the winter.
Winterize Your Planter
Winterizing means preparing something for winter or proofing it against the extremes of winter weather. There are 2 characteristics of concrete planters that make them require winterizing:
- They are porous and will absorb moisture from the snow. If the planter is poor quality, it can expand with moisture and crack.
- They are heavy and can be difficult to move inside for safekeeping over winter.
To safely leave your concrete planter out in the winter, winterize it using these steps:
- Empty the planter of potting soil.
- Thoroughly rinse the planter to remove soil residue. You can also disinfect the planter with a mixture of water and household bleach at a ratio of 9:1, respectively.
- Leave the planter to dry completely. Moisture that’s left in the pores of concrete planters can still expand and contract under the frigid winter temperatures, thus causing breakage and cracks.
- Cover the concrete planter with a tarp or plastic to keep away moisture. You can turn the planter upside down before covering it if its weight allows you to do so. Turning the planter will keep snow out of it should any moisture find its way inside.
Add Plants That Survive Winter
Large concrete planters or those on a pedestal will be difficult to move around. They are also hard to winterize using the above steps. If you have one of these, you can opt to make a winter garden in the concrete planter.
Evergreens and other winter pot plants that withstand freezing winter temperatures can be added to large concrete planters. Both the pot and the plants will give an aesthetic effect in a season when most garden plants die or hibernate.
Winter potted plants that you can consider for your concrete planter garden include:
- Violas
- Erica carnea
- Pansies
- Clivia
- Gaultheria procumbens
- Sedum
- Hellebores
- Citronelle heuchera
- Ivy
- Boxwood
Choose the Planter’s Location Well
If you have a large concrete planter, you can anticipate leaving it out in the winter. Do this by carefully choosing the planter’s location from the very beginning.
Since accumulated moisture from snow can cause damage to the planter, setting the planter in a location that receives direct winter sun can help evaporate the moisture from the concrete.
Additionally, locations with a shade that keeps snow away from the planter are an excellent option for large concrete planters that cannot be moved inside during the winter season.
The Bottom Line
Can concrete planters be left out in the winter? Yes! Concrete planters are made of strong, durable material and can resist the extremes of winter temperatures.
However, poor-quality concrete planters can absorb moisture, expand and crack if left outside during winter.
If you have small-sized concrete planters, opt for the safest bet and move them inside. If your concrete planters are large and hard to move, use a tarp cover to protect them from snow moisture.
