If you want to prolong the durability of your vegetable planters and retain moisture in the soil for a long time, you need to line your planters. There are liners of various materials in the market. Among them, plastic liners are cheap and easy to DIY. However, you may wonder whether or not it is safe to line vegetable planter with plastic.

Although chemicals of plastic leak into the soil and eventually into your plants, the dose is not lethal for the human body. To minimize the amount of chemicals, you should use plastic liners that are food safe.

In this article, I will tell you about using plastic liners for vegetable planters, and explain what type of plastic liner is safe for your vegetables. But you may also think, “If not plastic, then what should I line my raised bed with?” So, I will also suggest some alternative liners. 

Lining a Vegetable Planter with Plastic

Growing vegetables in planters or pots are on the rise nowadays. There are various kinds of planters based on material, shape, and size. If you have planters made of plastic, ceramic, or other materials unaffected by water, you may not need a liner. However, planters made of wood, metals, and clay need liners like plastic pots or sheets. 

Plastic liners prevent the planters from degrading quickly. Wood planters eventually get damaged, and you have to change them. But without proper lining, wood planters are affected by water and fungus. Thus, they degrade faster. So, putting plastic liners around wood planters is important to protect them. 

Clay planters easily take in the water of the soil. As a result, the plants may not get enough water. A plastic liner puts a barrier between the soil and the clay planter. Thus, it keeps the soil moisture for a long time as water cannot seep into the clay. 

Besides, plastic liners keep the soil together and control soil loss. You must have seen that a lot of people do not remove the plastic when they plant in pots. Plastic liners become extremely convenient when you are using a planter above the ground or hanging planters. 

As you can see, plastic liners are used quite often as liners. There are a few reasons behind it. First of all, plastic liners are available and easily made at home with plastic bags. Secondly, it is cheaper compared to other liners. And, thirdly, you can have food-safe plastics that are safe for your vegetables. 

Now, you have to be careful about the type of plastic used as liners for your vegetable planters. It is true that no matter what type of plastic you use, they will leach chemicals into the soil, and the plant will also absorb it. But chemicals are very much harmless if you use food-grade plastic. 

Which Plastics Are Safe for Lining Vegetable Planters?

Different types of plastics are made of different types of chemicals. Hence, they break down differently and cause different reactions. Fortunately, the manufacturers give a recycle code and some details of the plastic jars, containers, pots, or bags. For example, you will find abbreviations like PET and PETE on the plastic. 

So, before you use a plastic pot or bag as a liner for your planter, make sure the plastic is food-friendly. Some types of plastics have been clinically approved to be food-safe. The types are PETE or PET (Polyethylene terephthalate), HDPE (High-density polyethylene), LDPE (Low-density polyethylene), and PP (Polypropylene). 

These types of plastics are used to store foods. Therefore, they are also safe for making plastic liners for your vegetable planter. The plastics have chemicals, but the level of toxicity is very low. They do not leak too much of their chemical content into the soil either. So, the plants will probably only absorb trace amounts of chemicals.

Moreover, the chemicals may not even be absorbed by the roots. The microbes of the soil can decompose the chemicals, and lower the toxicity. The decomposition of the chemical depends on the type of chemical, the soil, temperature, and the number of microbes present in the soil. 

When talking about the lifespan of chemicals in soil we usually use the phrase half-life. So, if you find a chemical has a half-life of 12 -14 days, it means half of the chemical will be gone in 12-14 days. 

Besides, the vegetable plants in the planters are watered frequently. It is better to water planters with plastic liners until water comes pouring out of the drainage holes of the planter. It will help to wash away the toxic chemicals of the plastic liner, pesticides, and fertilizers. 

To be frank, there is a slim chance that the roots of your vegetable plants will absorb the chemicals. Even if they do, the toxicity level will not be too high to risk your health. The good news is the chemicals do not get evenly distributed into the plants. The dose will be high in the roots, but as it reaches the leaves, vegetables, and fruits, the level of toxicity becomes lower. 

How to Use Plastic As Liners for Vegetable Planters 

For your vegetable planter, you can use either a plastic pot or plastic sheets as liners. If you want to use a plastic pot as a planter, you do not need to use any liners. But plastic planters are not always stylish and/or decorative. That is why many people use planters made from other materials like wood, ceramic, clay, metal, and so on. But these decorative planters often have a shorter lifespan than their plastic cousins.

A good solution would be to get a plastic planter that is smaller than the decorative planter. Make sure the plastic planter fits into the decorative planter and has a hole for drainage. Then put the soil and plant your vegetable plants. 

The plastic planter will work as a liner, and the other planter on the outside will not get rotten or damaged so quickly. The water will also stay for much longer, which will keep the plants healthy. 

Besides, you can also use plastic sheets or food-friendly polyethylene bags as liners for your vegetable planter. Here is what you have to do:

  • Measure the length and the width of the planter. 
  • Mark the areas where you want the liners to be.
  • Cut the plastic sheets or bags according to the measurement.
  • Next, press the liners inside the planter and press firmly into all the corners. 
  • Make sure to secure the liners in the planters. You can use glue or staplers.
  • Make sure the liners have an opening at the bottom so that extra water can get out of the pot. 

When you are using plastic sheets and bags as liners, you have to change the liner every few months. The liners eventually tear because of heat, water, and the roots of the plants.  

Other Materials to Line Planters

So, plastic liners are safe for a vegetable planter as the toxicity level is low. However, if you are still concerned about using plastic liners for growing vegetables, you can use other liners of different materials. Here are other liners you can use: 

  • Metal Liners
  • Coconut fiber liners
  • moss
  • Landscape fabric 
  • Copper liners

You must know that some of these lining materials can also leak chemicals into the soil. So, before you use any liner, research the material and find out how the chemicals can affect your vegetable plants. 

Conclusion 

Now you should have a good idea of whether or not is it safe to line vegetable planter with plastic. Plastic is widely used as planter liners, not only because it is cheap but also because it is safe for growing fruits and vegetables.

However, it is wise to know about the safety of the plastics liners before you use them in your vegetable planter. Thanks for reading till the end and have a nice day!