When planting Euphorbia characias subsp. wulfenii, it's generally not necessary to add compost or enrich the soil unless the soil is very poor, as this plant thrives in well-drained, moderately fertile soil. However, if the soil is particularly sandy or heavy, you can work in some well-rotted compost to improve structure and drainage.

Water thoroughly during the initial establishment period, but once settled in, it prefers drier conditions and should only be watered sparingly. Avoid waterlogged soils, as they can lead to root rot.

Each stem is biennial, so will produce leaves in its first year and flower in its second. Once the stem has produced a flower it should be cut right back to its base, or to a point where there is new growth emerging, in midsummer. This will make way for lots of new, fresh shoots.

When working with spurges always wear gloves since the milky sap is poisonous and a potential skin irritant. Remove seedlings as they appear.