Temperatures averaging 60°F/°15.5C - 75°F/23.8°C is ideal from spring to fall and a cooler 50°F/10°C – 55°F/13°, after this period.
The Pencil cactus thrives on bright light and sun light, although direct sun when blazing hot is best avoided, when first introduced to direct sun.
It's advisable to water this plant more often within the summer and much less, winter time. Like other desert type plants, their natural habitat is dry and they store water within the stems. Water this plant when the soil begins drying out, throughout spring and late summer. In late summer reduce watering until the next spring and allow the soil to be fairly dry.
A fast draining pot mixture used for cactus plants is ideal.
While they're young they can be re-potted each year in spring. Once they mature re-pot only when necessary, with a slightly larger pot.
No misting is required. A well ventilated room during the summer is preferable.
This Euphorbia is propagated with cuttings from the stem top (especially when it's growing too high), or offsets during spring or summer. They can also be propagated with seeds at temperatures from 70°F/°21C - 80°F/26.6°C, although this method is much more difficult than propagating cuttings. When using cuttings, allow the cutting a week or two to dry before planting in a peat based compost.