Browningia hertlingiana also known as the “Blue Cereus” is a huge columnar cactus sought after by collectors because the juvenile specimens have a beautiful blue frosty covering. It one of the few really blue cacti.
Browningia hertlingianais a much decorative relatively frost hardy summer grower species. Still with it's blue colour and gold spines the plant is stunning even out of flower. Growth rate: The plant supposedly grows pretty slow. Soil: Grow it in a rich and particularly draining substratum, as it is very sensitive to rottenness when in presence of humidity and low temperatures and let the soil dry out between waterings. Repotting: Repot in the spring, when their roots become cramped. Generally, they should be repotted every other year in order to provide fresh soil. After repotting, do not water for a week or more. Use a pot with good drainage. Fertilization: It grows much faster with a low nitrogen content fertilizer in spring and summer. Watering: Water regularly from March till October, the thin, fibrous roots suffer if there is humidity, therefore the plant should be watered only when the surrounding terrain is dry. Keep dry as soon as the temperature starts dropping in October and keep it perfectly dry in winter at temperatures from 5 to 15 degrees centigrade. Preferable not to water on overcast days, humid days or cold winter days. Hardiness: They need to be kept in a cool place during winter rest and are somewhat resistant to frost if kept on the dry side prior to, and during, cold weather with little danger of being killed (unlike most of the Pilosocereus species). They are hardy to -5 C ° C or less, for short periods. However, in cultivation, it is better not to expose it to temperatures lower than 5° C, even if in an aerated and protected location. Although it is one of the easier Browningia to grow, it tends to rot in winter during the resting phase, if kept wet. In the rest period no high atmospheric humidity! Outdoors this plant is very adaptable, as long as you avoid excessive humidity in the winter months. It needs full sun exposures with ample airflow for best appearance.