Recycle plants: how to reuse or recycle plant pots and soil

It is inevitable. Plants do not last forever. But we do not necessarily have to throw away the entire plant. There are ways we can reuse or recycle potting soil, old pots and other recyclable materials.

Recycling plant pots, potting soil and biodegradable materials help us save money as well as the environment.

If plants die from pests or other diseases you should always throw away the entire plant and also consider disposing of the pots. These plants do not even go on the compost. It is not worth the risk. The plant pots can be reused only after being sterilized or cleaned using boiling water.

But most of the time there is a tried and tested way to recycle the pot and plant whether it is recycled at home for use in your garden or disposed of in a recycling bin.

And remember, recycling plant pots and soil will help the environment as well as save you money. After all, growing plants can get costly and we should all try to work in a sustainable manner.

Why we dispose of plant pots

There are several reasons why we dispose of pots. But I would argue that there is almost always a way to recycle or reuse.

Disposing of annuals and perennials beyond rescue

Sometimes, annuals and perennials alike simply come to the end of their lifespan. Leaves start to turn brown around the edges and the plant looks limp. And as we have already stated you should always throw the entire plant when pests or diseases are involved.

But most of the time it is simple down to the plant reaching the end of its lifespan. This of course especially true with annuals or herbs and vegetables that are grown as annuals like basil, coriander (cilantro), peppers and tomatoes.

There are also plants that die from overwatering, too much light, not enough light, bad drainage or a pot that simply does not offer the plant enough space to breathe and grow.

Pot plants need to be divided

Another reason we get rid of pot plants is when a plant grows too big and needs to be divided and repotted.

Consider growing more herbs from cuttings from large and healthy plants. Basil, sage, thyme, tarragon, lemongrass are only a few examples of herbs that propagate really well from cuttings.

This happens a lot in our garden when for example perennial herbs like rosemary, tarragon, thyme and oregano get woody and stop producing the delicate leaves we want to harvest.

Simply cut back the plant and look for new growth close to the base of the plant.

Divide the root system and ensure you have new growth above ground and a healthy root system to plant.

You have two options with plants that need to be divided:

  1. choose to dispose of them or 
  2. take the path of recycling 

We prefer recycling and every season use recycled pots, soil and biodegradable matter in our garden as well as cold and hot composts.

Composting is a great way to recycle organic matter. Learn all you need to know about composting in our article: 23 essential composting tips for beginners

Checking if the pot plant is dead or alive

Before recycling, you should make sure that the plant is indeed dead. After all, pot plants that wilt and die down are not necessarily dead.

Perennials, treated the right way, will for example come back again year after year, for example hydrangeas, geraniums and agapanthus. Herbs such as rosemary and lemon balm will also lie dormant over winter, but will come back again the following year.

If you are unsure, there are easy easy ways to check if a plant is dead or just dormant.

Start by scraping off the top layer of a branch and look at the color. If the inside is green you have a live plant. If the inside is brown, grey or black you have a dead plant.

New growth on herb plant that grew too big.

New growth at the base of an old pot plant
New growth on herb plant that grew too big.

Next cut back the plant and check for new growth at the base of the plant.

New sprouts may be small but the color should be bright green.

If you can see new growth you have a live plant. If there is no new growth you need to look at the root system.

Remove the plant from the pot and look at the root system.

A healthy root system is white or tan colored and looks plump and succulent. There is no bad odor.

How to save lacklustre perennials?

The general rule is to bring your pots inside to protect perennials from frost and winter temperatures which can easily kill them. 

At the beginning of the winter, place your pots where they have light and a cool temperature. 

Remove dead flower heads and leaves. Water until you see the water just beginning to run out of the bottom of the pot.

From now on, water sparingly only when the soil is dry. Do not give feed or fertilizer at all during the winter.

When spring comes and the weather is at least 12 degrees Celsius (55 degrees Fahrenheit) outside, gently lift the perennial out of the pot, shake off the soil over an outdoor flower bed. Careful not to damage the root system. 

Wash the pot thoroughly with your garden hose to get rid of any pests. Place fresh new potting soil mixture into the pot. If you have a large, tight root system and if the perennial has been in the same pot for at least two seasons, you may want to consider using a slightly larger pot now to give the roots more room to grow and develop.

Plant in new soil, pressing gently but firmly around the base. Trim off the previous year’s old stalks to make room for new growth. Water your plant which is now in it’s new soil and pot for the coming season.

Move outdoors for a few hours each day for a couple of weeks. As your plant acclimatizes again to the outdoors, you can move them outside completely. 

At this point we recommend watering with an appropriate liquid feed, the extra nutrients will give the plant a good boost to start producing new leaves and flowers for the coming season.

Recycling pots and soil

But what do we do with dead annuals and perennials at the end of the season?

Composting annuals and perennials

Both annuals and perennials are cut into small pieces and added to the compost.

The one exception to composting organic materials would be if there are signs or evidence of pests and diseases. If so, it is important that both annuals and perennials are disposed of and destroyed to prevent further spread.

Recycling soil

Always make sure to reuse the soil. Remove the plant from the pot and shake it over a large container. Let the root system dry out if the soil sticks to the roots.

The soil you harvest will have lost most of its nutrients and structure. Nutrients and structure can be added or use the soil as it is for seeds. 

Just make sure you bake the soil in a hot oven for 20 minutes before use to get rid of any lingering pests and diseases.

Yes, it is that easy.

Recyclable materials like plastic pots

Rinse and wash your pot thoroughly and it will serve you well for many more years to come.

Most gardening enthusiasts have stacks of pots made from plastic that are being used over and over. And you should treasure your pots regardless of size and material. There are good uses for pots of all sizes.

I for example have hundreds of recyclable starter pots in the range of 7-10 centimetres (3-4 inches). For me they are valuable as I can try new things to plant or transplant without having to use a lot of potting soil.

And whereas I am more aware and strict with the materials that I use today, I make sure that the pots I already have are used over and over again rather than creating more landfills and waste disposal sites.

Give your pots a new lease on life

We all know that buying new pots can be expensive. If you are tired of your old pots but spent a lot of money buying them several years ago, here are some ideas to give them a new lease of life by painting or stencilling them. 

Some of the most charming gardens I have visited have been those with a personal touch. A collection of pots of different colors and styles can add an eclectic mix to your front porch or green house. 

Identify the type of material your pot is made of then tell your local hardware shop what kind of paint you need. You can do fun things with ceramic, glass, metal, terracotta and plastic pots. Choose a color and get painting!

Try hand painting, stencilling or using stamps of various designs to add a completely unique and personal feel to your garden space. When the paint is dry remember to glaze your pots and they will last for years to come.

Recycle your pots when you are done with them

Sometimes we are just done with a particular pot or container. But instead of just throwing the pot in the trash there are at least 3 ways to recycle your pots.

1. Talk to your friends and neighbours
Remember, there could be other garden enthusiasts willing to take the pots off your hands. 

2. Check with your local authorities
Today most areas offer to recycle plant pots for free. Where we live it is in cooperation with the local waste disposal company.

3. Talk to your local garden center
Pot take back programs become more and more common. And if your local garden center do not offer such a take back program today, do make sure to ask them why. A thrown pot is a wasted opportunity of growing beautiful plants.

Frequently asked questions

Meet the author: Mattias is an experienced gardener spending most of his free time on his knees among herbs, plants, and garden vegetables. For the past two years, he has been sharing gardening projects and how-to tutorials on the NordicLavender website and YouTube channel.