Can Cement Harm Plants? Yes! Here’s How

If you’re looking for a short answer, then yes, cement is harmful to your beloved plants.

We have gathered proper information in this article for you to understand how and why cement is bad for plants.

But first, let’s clear one thing up. Cement and concrete are not the same things. Cement is an ingredient used to make concrete. That explains why concrete planters are okay for plants. It’s the cement from the concrete mixture that is dangerous for the plants if they come in touch.

While using cement and concrete you have to be aware of acid rain as this can lead to dangerous situations. Because acid rain has weak acids that dissolve the cement. So, using soil that has dissolved cement in it for plants, will result in unexpected situations.

Now, let’s dive into the details of the cement causing harm to plants. We’ll try to cover all the fine details.

Chemical Ingredients Of Cement

Cement is a composition of several chemicals. The chemicals include silicon, sulfate, calcium, calcium oxide, aluminum, silicon oxide, iron oxide, alite, sodium oxide, belite, and potassium oxide. These chemicals react with each other upon mixing and produce cement.

All the chemicals in the composition have a role due to different properties. For example, some elements will help reduce the melting temperature while some will be in charge of the slow hardening process, and many more.

Since the cement is a binding agent, it can’t be used alone for construction purposes. The cement’s job is to harden and keep all the materials stuck together.

What Effect Does Cement Have On Soil Acidity?

After all the introduction, now the burning question is…

How does cement harm plants?

Limestone – a compound named calcium carbonate is found in the cement that has a direct effect on the soil’s pH level.

For your better understanding – a low pH level means acidity and an increased pH level means alkalinity or basicity.

The limestone increases the pH level in the soil boosting it to a high alkaline level. The high pH level in the soil disturbs and reduces the mineral solubility in the soil. Plants’ normal pH level is between 6.5-7 means they’re mildly acidic. Hence, the plants find it hard and struggle to absorb the minerals from the soil.

While cement naturally contains alkaline properties – meaning cement has a high pH level already, mixing it with the soil will drastically change the soil’s pH level. Once the soil and cement are mixed, the pH level of the soil spikes up and makes it alkaline.

So, you should be very careful about mixing the cement and soil.

Another thing you should keep in mind is that the soil near any construction site has a high chance of being exposed to cement. The same goes for the sidewalks near construction sites or any DIY project site. Soil’s exposure to cement will destroy the plant’s growth drastically.

pH and Plant Growth

The healthy greeneries you see around you are due to the nutrients the plants absorb from the soil. While there are different minerals available in the soil of different regions, and the required minerals also vary depending on the plants’ growth, a slight change in the pH level can cause the plants to have zero growth or worse – death.

For a plant’s healthy growth, the required normal pH level is 5.5 to 6.5. However, this growth can be easily interrupted due to an imbalanced pH level of the soil as the increased pH limits the available minerals and nutrition for the plants’ roots absorption.

Bacteria and microorganisms produce the nutrition and minerals that the plants require for sound growth. And these microorganisms need an environment with an optimum pH range to survive and function properly so they can provide for the plants. Clearly, anything more than that range will hamper their procedures.

As we mentioned above, combining cement with soil will induce more acidity in the soil, consequently disturbing the whole process of the plants’ lives and growth. Moreover, the increased pH will destroy the helpful microorganisms and thus ruin the natural fauna in the soil.

Good News!

Although it’s only normal for the plants to require a calculated atmosphere – like a balanced pH – for safe and healthy habitation, there are plants that grow flawlessly in an alkaline environment. For example, succulents.

Succulents are alkaline environment-friendly plants. Frankly, succulents bloom better in the higher alkaline atmosphere. This trait makes succulents a perfect choice for your clement planters.

If you’re not into succulents, no need to worry. We have listed several options for you. The following plants will also do great in the cement planters and also withstand the higher pH level:

• Mums
• African Violets
• Morning Glory
• Begonias
• Easter Lilies
• Orchids

Also, there are several herbs and vegetables too that are cement planter / higher pH friendly:

• Arugula
• Broccoli
• Oregano
• Cabbage Chives

That should give you enough options to start decorating those planters.

Making Concrete Planters Safe For Plants

You have one more option available if you really want to make things work with your favorite plant that loves an acidic environment.

The easy fix?

Just change the pH of the soil.

Don’t raise those brows yet. Yes, it’s possible.

Go to the store or online shops and find some sphagnum moss, iron sulfate, or organic mulches. Add them to your soil and alter the pH level.

Now, don’t get your hopes high because this might not always work 100%. That’s why we have backup solutions too.

For a long-term solution, you’ll have to soak your cement planter in water for at least three days. This method will draw the alkalinity out of the planters and help the planter reach a decent pH level that’s safe for the plants.

You can also try leaving the planters out in the rain for a couple of days before you start planting.

There’s one more approach to this problem. Sealing the planter with a resin or acrylic sealant. While sealing your planter can undoubtedly save the plants from harmful chemicals and life-threatening situations, the purpose of using cement planters will be gone for good.

The cement planters are not only just beautiful on their own, but they also serve a very important purpose. Their unsealed and porous material helps the plants big time as they control watering and prevent the water from getting stuck at the base.

So, make sure you take that under consideration before sealing your planters.

Conclusion

The bottom line is that the cement in your soil or planter can be deadly for your cherished plants.

So, it’s better to take preventive steps than to find a cure after the damage has been done. Because the harmful properties present in cement will definitely destroy your plants’ survival rate.

Hopefully, our article will be able to guide you in the right direction.