Worms will not eat healthy, growing plant roots but will eat and break down dead roots. This is great for plants as it makes room for new roots, releases nutrients into the soil. Plants will naturally replace old roots with new ones throughout the year and worms help to break the old ones down.
Worms will not eat healthy plant roots in pots but it is best not to deliberately put earthworms or composting worms in plant pots. It is better to use worm castings from a worm farm to improve the potting soil and add nutrients.
Worms and soil bacteria move in to break down old plant roots in a natural composting process that returns the nutrients to the soil. This is a great way to refresh your soil without you having to do anything.
When I have an annual plant that has finished for the season, simply snip off the top and leave the old plant roots in the ground. Let worms feed on them and break them down.
Leaving old plant roots in the ground is also great to support the growth of soil bacteria and healthy fungi. While digging up soil can disturb the balance, leaving the soil and letting the worms do the work helps to allow it to improve on its own.
Benefits of worms for plant roots
There are many benefits of worms in the ground or raised garden beds for plants. Here are the top benefits of worms for plants and their roots.
1. Worms mix organic matter deeper in the soil
Worms will dig up from the deeper soil and will mix organic matter through the soil. They will break down mulch, aged manures and mix soil pieces together. This will create a perfect soil combination over time to support plant root health.
Worms will mix organic matter from the surface of the soil and take it deeper into the soil as they consume and digest it. This will bring nutrients and organic matter down to the deeper roots of the plant. This will encourage plants to grow deeper roots.
2. Worms will aerate the soil
When worms dig through the soil they will make small air pockets which allow spaces for roots to grow and expand. These tiny diggers will work the soil over, lighten the soil and allow the roots to grow larger and quicker.
3. Digest old plant roots
Worms will dig through and eat and digest old plant roots. As plants grow, they will replace their small and large roots over time. Worms work as natural cleaners and will help to clear up the old roots and remove them making room for the new ones.
Worms can also help to clean up old plant roots in the ground. Small plants that have died off, finished for the season or even weeds can be eaten by worms. If the roots are no longer growing and not attached to a healthy plant then the worms will move in.
Soil bacteria will also start to digest plant roots that are no longer growing. Worms will eat and digest the bacteria that are breaking down the plant roots, releasing the carbon back into the soil.
4. Allow the natural soil bacteria to grow
Worm will live in harmony with a healthy soil bacteria population. Soil bacteria will break down organic matter and release nutrients for the plant. Worms can work in harmony with the soil bacteria to break down larger pieces of organic matter and the soil bacteria themselves.
This healthy eco system created with the worms means that the soil does not need to be dug over and disturbed. Rather than digging through organic matter, you can layer cow manure, compost and mulch as a top dressing and allow the natural soil life to mix it through.
5. Deep digging worms bring nutrients up to the surface for plant roots
Different worm species live in different layers of the soil. They will also dig down deeper or stay shallower depending on the weather, soil type and rainfall. Deep digging worms will bring minerals up from the deeper levels of the soil.
This helps the plants to get the nutrients they need from soil levels that their roots may not be able to reach. Worms also break down the rock and sand particles to make the nutrients available for the plants to absorb through their roots.
Do worms kill plant roots?
Worms will not kill healthy plant roots that are growing well. Worms will not have any significant negative impact on plant roots but instead will help to release nutrients for them to grow. Small, natural populations of worms will not cause any damage to healthy plant roots, even those grown in pots.
Are worms bad for roots?
Worms are a great companion for plant roots and will help to break down natural organic matter in the soil. This will help to release nutrients to allow them to be absorbed by the plant roots. Worms will also aerate the soil and work in harmony with soil bacteria to mix through organic matter.
Are worms good for plants in pots?
Worms can survive in plant pots if they are provided with lots of aged manures, compost and good soil. If a normal potting soil is used worms will usually head out of the pot to find more food. I have added worms from my worm farm to pots and they have survived well.
This works if the soil is rich in organic matter and the soil is refreshed regularly. You do not need to add worms to plant pots because worms can escape and will move out if the pot dries out.
Leave earthworms in the soil and composting worms in a worm farm. Instead, mix through worm castings into your potting mix. This brings all the nutrients and organic matter and leaves the worms to make more in the farm.
Do worms destroy plants?
Worms do not destroy living plants but will break down and digest dead and dying plants. Once the roots, leaves and stems start to break down then worms will move in to break it down. Worms love to digest organic matter that has already started to rot down.
I have noticed that worms in my worm farm will digest the oldest fruit and vegetable scraps before the new ones. Soil bacteria move in first to break down food scraps, old plants and roots and then worms will usually move in next.
Do Worms Eat Plant Roots? | Summary
Worms will not eat healthy plant roots but will break down and digest old, dead roots. This is the natural way that the plants will refresh their roots and the worms can make room for new roots to grow. The roots will be broken down releasing the carbon and nutrients into the soil.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.