Pencil cactus is a species of Euphorbia (spurges) and not a cactus as its name might indicate. The plant is succulent, thus doesn’t have any leaves.
Pencil cactus is also called the Firestick plant.
Why is my Pencil Cactus turning yellow?
Pencil cactus turns yellow when it gets a lot of water. The pencil cactus plant also turns yellow if it gets injured or ages.
Injury
Sometimes when the plant is injured, the connection to the broken part is lost. The injured part won’t get any nutrients or water which causes this yellowing.
Eventually, that injured part will fall off the plant as it has no physical or nutritional support from the plant.
Overwatered Pencil Cactus
Giving your Pencil cactus more water than it needs is a strict no! Pencil cactus is super drought-tolerant. They like to be watered minimally.
Pencil cacti are native to arid regions which means they can tolerate a lack of water for a good time. Water only when the plant is thirsty.
How often do you water a pencil cactus?
You need to let the soil dry out completely before watering again. Check the soil with fingers and do not water if it is moist.
When the plant is in a growing phase or it’s summer, watering the plant fortnightly would suffice. Watering less is always better for succulents.
If it is winter then you need to water the plant once a month. Pencil cacti are susceptible to root rot. You need to make sure you are not increasing the chances of root rot.
Aging
Yellowing of pencil cactus occurs due to aging too. This is a natural process and the lower branches of the plant fall off.
There’s nothing you can do about it so you don’t need to worry about this at all. Just let the plant live its life.
Why is my pencil cactus turning red?
It is completely normal for the pencil cactus to turn red. After all, this is the natural color of the plant. If the plant is in a healthy environment it turns red.
Pencil cacti turn red when the environment is cold and the sun is bright enough. Pencil cactus turns red/orange and that’s why it is called the Firestick plant.
The plant should stay in the intense sun to turn itself red/orange. This color is the reason why they’re grown. It is the top part of the stems that should turn red/orange.
The plant turns a little green when it rains. If a part of the plant is in the shade it turns green.
Why is my firestick plant not red?
If you give your Pencil cactus more water than it needs then it doesn’t turn red. Your plant also doesn’t turn red if it doesn’t get enough sun.
Try to put your sun in bright, intense sunlight. Just water your plant only when it demands some. Check the soil with fingers if need be.
Does pencil cactus need full sun?
Yes, pencil cactus plants need direct, intense sun to thrive. They are succulent plants that are native to arid places with a good amount of sunlight.
If you are growing your plant indoors, place it near a west, south, or east-facing window for maximum exposure to the sun.
Pencil cactus grows best when it is grown outdoors. People who grow it indoors find it hard to give light to this plant. Keep this plant as close to the window as possible and it should thrive.
Pencil cactus shriveling
Pencil cactus shrivels when it gets too much water. The plant becomes unstable and droopy. The symptoms are so visible because pencil cactus doesn’t fancy overwatering.
The branches may look brittle and people might think that it’s because of underwatering. No, it’s not. This happens when the plant gets too much water.
Branches turn greyish brown and fall off eventually. Feel the soil with your fingers and you’ll see that it is moist.
Always water your pencil cactus sparingly as overwatering leads to root rot in many cases. Let the soil dry in between the watering sessions.
Make sure your soil drains well. Poorly draining soil/water-retaining soil causes waterlogged conditions. Try to get a potting mix with 25% sand to increase the draining ability of the soil.