A plant collar can help to protect your plants against common pests, including cutworms and cabbage root maggots. Plant collars are often called brassica collars, broccoli collars, or cabbage collars, but they can also help to protect tomatoes and other plants as well.
So, how do you make a plant collar? You can make a plant collar out of cardboard tubes or boxes, plastic cups, metal cans, pipes, or combinations of these materials. Most likely, you have some materials around the house that you can recycle to make plant collars.
Of course, plant collars will add a little extra effort to your gardening. However, it is worthwhile to protect your plants from devastating pest damage.
In this article, we’ll talk about how to make plant collars and the different materials you can use. We’ll also talk about some benefits and drawbacks of each.
Let’s begin.
How To Make A Plant Collar
There is more than one way to make a plant collar. You can use a variety of materials as the basis for a plant collar, including:
- Cardboard
- Plastic
- Metal
- Cloth
Let’s start off with a common and cheap option: cardboard
Cardboard Plant Collars
We want a plant collar in the shape of a cylinder, with an open top and bottom. A few options that don’t require much work include:
- Toilet paper roll tube – once the toilet paper is used up, just take the cardboard cylinder and use it as a cutworm collar. You might be able to cut the roll into two or three collars. However, make sure you make the collars tall enough to deter pests and keep them away from your plants.
- Paper towel roll tube – a leftover cardboard tube from a paper towel roll is longer than a toilet paper roll tube. As such, you can cut it into several cutworm collars.
- Fabric roll tube– after a roll of fabric is used up, the leftover cardboard cylinder will give you enough material for many plant collars. You might be able to find this item from an upholstery shop, a fabric supply store, or a craft store (such as JoAnn’s, Michael’s, etc.)
- Long cardboard tube – these are often used for shipping or mailing. If you or your workplace receive these tubes, you might be able to cut them up and use them to make plant collars.
You can save these cardboard items all winter to prepare for spring planting!
Of course, if you can’t find cardboard tubes, you can also use flat pieces of cardboard to make circular plant collars. All you need to do is curl the cardboard into a tube and secure the ends (a few staples should do the trick).
You can use cardboard boxes to supply the material for your plant collars. Just flatten the boxes and cut them into pieces that are the right size for your collars.
Here are some sample dimensions for a plant collar.
Let’s say you want to make a plant collar with a diameter of 2 inches and a height of 4 inches.
The circumference of the plant collar is 3.14 x D (pi times the diameter). The diameter is 2, so the circumference is about 3.14 x 2 or 6.28 inches.
The height is 4 inches, so we would need to cut a rectangular piece of cardboard that is 4 inches by 6.28 inches. Then, we would curl the cardboard into a tube and join the ends with staples to make our collar.
Note: on the circumference (6.28 inches), we might add a little extra for “overlap” when we staple the ends together to secure the circular tube. A length of 6.5 inches would be enough.
The benefits of cardboard plant collars are that they are:
- Biodegradable – cardboard breaks down fast, so you won’t need to worry about picking up your plant collars at the end of the season.
- Cheap – you can get cardboard cheap or free in most cases.
- Flexible – cardboard is flexible and easy to work with.
The major drawback of cardboard plant collars is that they won’t last long. That means you will have to make new ones every year.
Note: if you combine cardboard with another material, you can make your plant collars a bit more sturdy so they will last longer.
For example, let’s say you wrap aluminum foil or plastic around a flat piece of cardboard and then curl it into a plant collar. The collar will now be protected from water and soil, so it will take longer to break down.
Plastic Plant Collars
There are lots of plastic items that are already in the shape of a cylinder. This makes them perfect for plant collars.
Here are just a few items you can use to make plastic plant collars:
- Plastic water bottles – once you cut the top and bottom away from a bottle, you will have a plastic plant collar. With taller bottles, you might be able to cut two or more collars. A larger plastic gallon container will give you a wider cloche for plants that tend to spread out more. This is similar to the idea of using a plastic bottle to make a plant cloche.
- Plastic pipe – some types of plastic pipe are flexible and easy to cut, such as those used for irrigation and drainage systems. If you cut one of these pipes into short pieces, you can make plant collars. If you are replacing an old pipe that has a few holes in it, you might be able to salvage several plant collars from it.
You can also use a flexible plastic sheet to make a plant collar. The same concept we used for cardboard plant collars would apply here.
The dimensions for the length and width of the rectangular plastic sheet are:
- Length = height of the plant collar
- Width = pi times the diameter of the plant collar (3.14 x D)
You may find that staples will not work to secure the ends of the plastic sheet together. In that case, you might want to use glue to hold the ends together.
The benefits of plastic plant collars are that they are:
- Durable – they will last a long time and can be reused (some plastic won’t hold up well in the sun, though).
- Cheap – you can find plastic bottles in your house or from neighbors without much trouble or expense.
The main drawback of plastic plant collars is that they are not biodegradable. If you lose them in your garden, they won’t decompose for a long time.
Metal Plant Collars
If you search around, you can find metal items that already have the shape you need. Other items are flexible enough to suit your purposes to make a plant collar.
Here are a few items you can use to make metal plant collars:
- Aluminum cans – any aluminum can that holds soup, vegetables, or fruit can have a 2nd purpose in your garden. Use a can opener to remove the top and bottom of the can. Then, you have a perfect metal cylinder to use as a cutworm collar.
- Aluminum foil – cut the bottom out of a paper cup. Then, wrap aluminum foil around the cup and use that as a plant collar. The aluminum will prevent the paper from decomposing, at least long enough for your plants to grow without being bothered by insect pests.
You can also use a flexible wire mesh to make a metal plant collar. This method may not work by itself, but it will work great when combined with plastic.
First, cut the wire mesh into a rectangular piece with the proper dimensions – as before:
- Length = height of the plant collar
- Width = pi times the diameter of the plant collar (3.14 x D)
Then, curve the wire mesh into a circle around the plant so that the ends meet.
Finally, wrap plastic around the outside of the wire mesh to make it insect-proof. As long as the collar is tall enough, cutworms and other pests will have a hard time climbing it.
The main advantage of metal plant collars is that they are durable. They will probably last for many years, and they won’t break down like cardboard or crack in the sun like some plastic.
The main drawback of metal plant collars is that they are not biodegradable. It might be difficult to remove them from plants at the end of the growing season to reuse them the next year.
Other Materials For Plant Collars
Of course, you can use other materials for plant collars, including:
- Fabric Plant Collar (perhaps canvas or burlap, similar to what is used for grow bags)
- Felt Plant Collar (you or someone you know might have some leftover from a craft project)
- Rubber Plant Collar
Follow instructions similar to the above when cutting the dimensions for fabric or felt collars.
How To Prevent Cutworms
There are lots of ways to prevent or get rid of cutworms on plants. Plant collars (or “cutworm collars”) are just one way.
You can also use these methods:
- Diatomaceous earth (kills insects after contact)
- Removing debris (where cutworm larvae can grow)
- Welcoming birds (which prey on cutworms)
You can learn more about how to get rid of cutworms in my article here.
You might also be interested in reading my article on the types of worms that eat tomato plants.
Conclusion
Now you know how to make a plant collar out of lots of different materials. You might also get some inspiration for your own unique ideas.
I hope you found this article helpful. If so, please share it with someone who can use the information.
If you want to read some of my most popular posts, check out the “Best of GreenUpSide” page here. Enjoy!
~Jonathon