How to Get Rid of Capeweed Naturally

Written By:
Scott Carroll
Published On:
April 21, 2023

Capeweed, also known as Cape daisy, Cape marigold, or wild chamomile, is a pesky weed that can nuisance your garden. Additionally, this weed can be an even greater concern if you have any livestock in the area, as studies have linked Capeweed to causing nitrate or nitrite poisoning in sheep and cattle

While many chemical herbicides are available at any local store, we all know that they can cause more harm to the environment than good. Accordingly, we’ve provided you with a breakdown of 4 simple solutions to eliminate Capeweed and how to stop it from returning to your yard!

What is Capeweed?

Capeweed is a broadleaf weed that can grow up to 60cm tall. You can identify this weed from its yellow flowers and deeply lobed and toothed leaves.

The annual weed can reproduce quickly and spread quickly to other areas of your garden. However, Capeweed is commonly found in areas with poor soil health, over fertilised or lacking sufficient sunlight or air circulation. 

Why is Capeweed bad?

Capeweed is undesirable for your backyard because it can compete with other plants for water, nutrients, and sunlight. Consequently, this can cause surrounding plants to die over time. 

Additionally, Capeweed has a high burstiness, producing many seeds that can quickly spread and establish themselves in new areas. This can make it challenging to control and eradicate its growth once it has taken hold in an area. 

For this reason, we recommend treating Capeweed as quickly and efficiently as possible to avoid any further spreading or damage inflicted on your backyard. 

Flowering capeweed

What kills Capeweed naturally?

There are a few natural ways to kill Capeweed, the most preferred methods include:

  1. Vinegar
  2. Boiling water
  3. Spreading mulch 
  4. Solarisation
  5. Manual removal

Below, we will take you through each of these methods, explaining how you can do it and achieve the best possible outcome for getting rid of Capeweed. 

1. Vinegar 

Vinegar can be an effective natural herbicide to control smaller outbreaks of Capeweed in your backyard. You first want to select the right type of vinegar; we find that white vinegar with an acetic acid concentration of 5% or higher works the most effectively. 

Additionally, you want to ensure that you dilute the vinegar with water. We prefer to use a ratio of 1:1, as a higher concentration may cause damage to surrounding plant areas. If you are not concerned about your surrounding plants, you can use as much as a 2:1 vinegar-to-water ratio for your solution.

When applying the vinegar, use a spray bottle to apply the mixture directly onto the Capeweed. For the best results, you want to cover the leaves and stem of the plant thoroughly.

Depending on the size of the Capeweed patch, you may need to apply the vinegar mixture several times to kill the plant fully. Reapply the mixture every few days until the Capeweed has withered and died.

2. Boiling water

Boiling water is a simple, effective, and environmentally friendly way to control Capeweed growth. However, boiling water may kill other plants, so we recommend avoiding this method if you want to eliminate Capeweed or areas with other desirable plants.

This method simply works by bringing a large pot of water to a rolling boil and then covering the Capeweed several times. The boiling water effectively destroys the plant cells and causes them to wilt and die.

Similar to the vinegar approach, you may need to follow this method several times to kill the Capeweed fully and avoid any regrowth. 

3. Spreading mulch

Spreading mulch can help kill Capeweed by depriving the plant of sunlight and nutrients. However, it may take several months or even years to fully eliminate the plant, depending on the patch’s size and the mulch layer’s effectiveness.

The method involves spreading a layer of organic mulch, such as straw, wood chips, or leaf litter, over the area where Capeweed grows. Ensure the layer is thick enough to block sunlight from reaching the soil. 

Over time, the mulch layer may break down or settle, allowing sunlight to penetrate the soil again. As a result, you may need to add more to the area periodically to maintain the effectiveness of the mulch. 

Once the Capeweed has died, removing it from the area is important to prevent it from regrowing or reseeding.

4. Solarisation

Soil solarization is an effective and eco-friendly way to control Capeweed growth. It’s important to note that soil solarization can also kill beneficial microorganisms in the soil, so it should be used sparingly and only in areas where Capeweed is a significant problem.

For this method, you must remove any existing Capeweed, rocks or other debris from the area where you want to solarise the soil. 

Following this, you will need to thoroughly water the soil to a depth of about six inches to conduct heat more efficiently before covering the area with a clear plastic sheet. For the best results, we recommend using heavy-duty greenhouse plastic and completely covering the impacted area, ensuring that it is secured with rocks or some weight. 

After this, leave the plastic sheet in place for at least six to eight weeks, preferably during the hottest part of the summer. The heat from the sun will be trapped under the plastic and effectively “cook” the soil, killing Capeweed and other weeds.

5. Manual removal

Although labour-intensive, manual removal effectively controls small Capeweed patches or prevents them from spreading. This method is perfect if you’re worried about surrounding garden beds or plants. 

The best way to do this is to grasp the Capeweed plant as close to the base as possible and gently pull it out of the soil.

 When doing manual removal, you must remove the entire root system, as Capeweed can regrow from even small pieces of root. Once you’ve confidently removed all Capeweed from the area, place them in a bag or bin for disposal. We recommend avoiding composting your Capeweed as it can still produce seeds and spread.

What to consider before eradicating capeweed

Before eradicating Capeweed, there are a few things you should consider:

  1. Impact on the ecosystem: Capeweed, like all plants, plays a role. It provides food and shelter for insects and other small animals; its flowers are a food source for bees. Before eradicating Capeweed, consider the impact it may have on the ecosystem and whether there are alternative methods of control that may be less damaging.
  2. Timing: Capeweed is an annual weed that sprouts in autumn and flowers in spring. To be effective, control measures should be implemented early in the growing season before the plants have a chance to spread their seeds. 
  3. Size of the infestation: The size of the infestation will determine the most effective control method. For small patches of Capeweed, manual removal may be sufficient. At the same time, larger areas may require methods like solarisation, mulching, or herbicide application.
  4. Surrounding vegetation: Before applying any control method, consider its impact on surrounding vegetation. Some techniques may harm desirable plants, while others, like mulching or manual removal, may be more targeted and safe.
  5. Safety: When using any control method, safety should be a top priority. Wear protective gear, like gloves and long sleeves, when handling Capeweed. 

Considering these factors before eradicating Capeweed, you can choose the most effective and environmentally-friendly control method while minimising the impact on surrounding vegetation and wildlife.

How to stop Capeweed from returning

To stop Capeweed from returning, it’s important to use a combination of methods that target both the current infestation and the seed bank in the soil. 

Proper lawn and garden maintenance is critical for keeping your lawn healthy. This can help prevent Capeweed from establishing itself in the first place. Regular watering, fertilising, and mowing can help create unfavourable conditions for Capeweed growth.

Not your type of weed? Check out our guide on how to get rid of onion weed from your garden.