Pencil Cactus (Euphorbia Tirucalli) Grow & Care Guide

Written by Iris

Sep 22 2021

Pencil Cactus (Euphorbia Tirucalli) Grow & Care Guide
Pencil Cactus (Euphorbia Tirucalli) can be a petroleum plant, a medicinal plant, and an ornamental plant. Because of the Pencil cactus's drought resistance, salt-resistance and wind resistance, Pencil cactus is commonly used as a seaside windbreak or landscaping tree. The following will introduce how to grow and care for Pencil Cactus.

How to Propagate Pencil Cactus

You can propagate Pencil Cactus from stem cuttings. Take a cutting that is 4-5 inches (10-12 cm) long from a healthy stem using a sharp and sterilized knife. Gently remove the lower leaves, making sure you have a bare stem of about 2-4 inches (5-10 cm) long. Wipe the bottom layer with powdered rooting hormone and let it dry for a week or so. Before planting your cutting in damp potting soil, you need to wait for it to form a callus.
Fill a small container that has drainage holes with a suitable potting mix for cacti and succulents. You can also prepare your homemade mix from crushed rocks, perlite, or sand and some compost. Dip the stem cutting into the potting mix, place the pot in a bright and warm area, and provide it with plenty of water.
You will notice roots developing on your cutting in several weeks. Once the roots have grown, you need to transplant the baby pencil cactus into a larger container and water it thoroughly. Wait for the soil to dry out, then give your plant the usual care for Pencil Cactus.
Pencil Cactus

How to Grow & Care for Pencil Cactus 

Pencil Cactus Care - Light

In the garden, Pencil Cactus takes full or partial sun. Mine gets full sun in the summer but in late fall & early winter is shaded by 2pm. Indoors this is a high light plant – it needs sun & all the natural light you can give it.  Make sure it has a south or west exposure. If it’s not getting light from all sides when growing, then be sure to rotate it it every few months.

Pencil Cactus Care - Soil

Pencil cactus (Euphorbia Tirucalli) need to grow in sandy soil with excellent drainage. The ideal growing medium for Pencil cactus succulents is a cactus soil mix that doesn’t retain moisture. If necessary, you can work in perlite to the planting area to improve drainage for your succulent ‘fiery sticks’ to thrive.
Because Pencil cactus are ideal for rocky, infertile soil, they are suitable for rock gardens along with other types of succulents. Or, you can plant ‘sticks on fire’ in container gardens in your yard.
To create the ideal potting mix for growing Pencil cactus in containers, use a combination of cactus mix and perlite. Combine two parts of cactus potting soil with one part perlite. The plant soil for growing Pencil Cactus should be porous enough to allow water to drain quickly.
In general, you don’t have to worry too much about the growing medium for Pencil cactus. As long as drainage is excellent and it doesn’t retain too much moisture, you should have no trouble caring for your succulent Pencil cactus.
Pencil Cactus

Pencil Cactus Care - Water

Succulents store water in their fleshy stems and leaves, so you usually don’t need to water Pencil cactus succulent as often as you would other houseplants. Water about once every two to three weeks during spring and summer but stop watering completely during the winter months.

Pencil Cactus Care - Temperature & Humidity

Although Pencil cactus (Euphorbia Tirucalli) can tolerate temperatures from 25º-100º degrees Fahrenheit, it prefers temperatures ranging from 50º – 70º degrees Fahrenheit. Ideal temperature range is 65º – 70º degrees Fahrenheit for growing the Pencil cactus plant, so it does well year-round indoors at normal household temperatures.

Pencil Cactus Care - Fertilizer

Feed your pencil cactus (Euphorbia Tirucalli) liquid fertilizer once per year in the spring. Pencil cactus is adapted to survive in nutritionally poor soil and too much fertilizer can kill it.

Pencil Cactus Care - Pruning

Old branches can be removed or trimmed to maintain size and improve the appearance of your pencil cactus at any time of year. But, exercise caution when trimming Pencil cactus plants. The stems of euphorbia tirucalli exude a milky sap that is toxic. The sap does not need to be ingested to pose a danger, as it can also be absorbed through the skin and often causes skin irritations on contact.

Pencil Cactus Care - Pests & Diseases

Overwatering the sticks on the pencil cactus plant can be troublesome. If you overwater the plant and the soil has poor drainage, you’re going to get root rot underneath the soil. Make sure to water the Pencil cactus very infrequently, especially when the weather isn’t hot. Check the soil moisture and only water if you find it completely dry. Consider using a looser-textured mix if you find your soil holding on to too much water.
You will not come across any pest problems in pencil cactus in our experience. If you have, let us know down below and we’ll add prevention tips.
Pencil Cactus

 Pencil Cactus (Euphorbia tirucalli) FAQ

Is a pencil cactus poisonous?

The Pencil cactus succulent, found across San Diego County, is toxic to humans, dogs, and cats worldwide and can cause serious intestinal and skin injury, according to The American Society for the Prevention of Cruelty to Animals (ASPCA).

Why is my pencil cactus dying?

Generally a Pencil Cactus will become less stable, droopy, and turn greyish brown if it is receiving too much water. Pieces of the plant may turn grey and fall and although they look brittle, this symptom is often from overwatering.

Can pencil cactus survive winter?

Yes. Pencil cactus is strict to the environment, but its cold resistance is strong. When the temperature is below 10 ℃ in winter, the pencil cactus will enter hibernation and stop growing. When the temperature is below 5 ℃ in winter, it will be frostbitten, even death or wither. Then you need to control the temperature above 5 ℃, especially in the northern region, and give the Pencil cactus enough sunshine, which prevents frostbite.

Will a pencil cactus root in water?

A pencil cactus can be readily propagated from cuttings. Take a cutting of a green branch around 6 inches long, and dip it in fresh water to stop the flow of sap. Then, allow the cutting to dry for about a week and form a callous over the cut end before potting it in moist succulent or cactus potting mix.