Perhaps you have looked at your cactus spines and thought to yourself, “That cactus has funny colored spines?” You may have wondered to yourself if your cactus might even be unhealthy because of the color of the spines.
What color should my cactus spines be? Depending on the species of cactus, the spines range from red to yellow to green to gray to brown to black. In most cases, the color of the cactus spines don’t indicate health. The color of the spines have more to do with the species.
Don’t Worry Too Much About the Color
Let’s say that you see a cactus with black spines. In most cases, you don’t have to worry about the color. Black spines usually happen after rain that changes the color of the spines to black. If you’d like to learn more about black cactus spines click on an article that I previously article wrote here.
Like with black spines, you don’t have to worry about yellow or red spines either because red spines will usually indicate a mature cactus. Red spines have more to do with the natural process of an aging cactus. Click on my article about red spines here.
Yellow spines, on the other hand, have more to do with the species, in most cases. Provided the cactus looks healthy, don’t worry too much as long as the species is known for having that color of spines. Look up each species to learn what color spines are normal.
When to Worry About the Color of Spines
The spine color doesn’t indicate health but pay close attention to the overall state of the plant. For example, if the plant itself develops a black splotch on it, this could mean the start of disease. The color and quality of the spines in conjunction with the plant indicates a problem. If you can grab a cactus spine and pull it off easily, you have an unhealthy plant.
In some cases, deep brown cactus spines could mean the plant needs watering. It could also mean a high humus content in the soil or that the cactus has begun to die from the bottom up. You have to understand these things. In general, light brown spines don’t mean a problem. Usually, that shows the species of the plant. If you’d like to learn more about brown cactus spines click on my article here.
Why Cactuses Have Spines
Cactus have spines because they shade the plant from the sun in the desert, and they offer protection from animals that would eat it.
Getting shade from the spines in the sun prevents the plant from losing water. In the harsh heat of the desert, the plant could die if it didn’t retain water. This also explains why cactus spines will turn black after a watering. It has to do with the water content.
To be clear, you need to make sure that you have good drainage when watering the plant. Also, a gritty soil that doesn’t retain the water is best because this prevents root rot. You might look at cactus spines as a type of modified leaf.
The Spine Color Subject to Change
Don’t feel alarmed if one day you had red cactus spines and the next, you have brown spines. Brown spines on a cactus commonly happen when the cactus ages. The spine color that you start with can change over time. That and how most cactuses flower help to make this one of the interesting plants in the world.
Along with the color of the spines, the size of them varies from one species to the next. Some cactus will have nearly invisible spines, while others can reach up to 12 inches in length. To add to the fun, look for the patterns on the spines of your cactus. They will typically have specific patterns that form on each species.
How to Know When Your Cactus is Dying
The cactus spines will fall off the cactus when it starts to die. In some cases, the cactus will fall over, or it will be loose in the soil. To determine the health of your cactus, don’t pay so much attention to the color of the spines. Pay attention to the color of the plant. Brown or black or yellow splotches on the cactus mean that your plant has health problems of some kind.
Why Does the Spine Color Change with Water?
In the desert, the cactus spines serve another purpose. They can take in water from the air and bring it back to the cactus. Because of that, it should come as no surprise that as the spines get saturated with water, they will change color, often to the color black or red. Don’t worry. The spines will return to their normal color after they dry.
One thing to understand with this aspect, however, is that you don’t have a lot of species that will have their color change dramatically after receiving water. Usually, you will notice a slight change in the tint of the spine.
Soil Can Change the Spine Color
Soil with a high humus content can change the cactus spines closer to the bottom to brown. In soil high in iron content, the spines can change to the color red. The spine color might change because of the fertilizer, which contain nutrients. In general, you want to find a fertilizer with a rich variety of minerals.
How Cactus Spines Age and How It Affects Their Color
Cactus spines when they first appear will have a bright and vivid color, but as they age, they might start to lose their sheen. As said before, they might even take the color brown. This doesn’t mean anything bad. Newer cactus spines will always have a deeper color, and they will be thicker too. The thickness occurs because new spines have higher moisture content and older spines have begun to dry out.
Some people think of newer spines as healthier. That isn’t true. As the older spines lose water content, they will dry out, and they will lengthen while becoming thinner.
What color your cactus spines are will depend on the species. Don’t worry too much about the color of the spines. In most cases, it doesn’t have anything to do with the health of your plant. If you start to notice the plant itself turning color, this could be a bad thing. Many times, when the plant changes colors, it means pests inhabit the soil or your plant has taken on some kind of disease.