Blue Chalk Sticks, Senecio serpens, is one of those plants I love using when a garden needs a completely different foliage colour. That incredible chalky blue-grey almost looks unreal, and when you plant it alongside fresh greens, deep burgundies or even silver foliage, the contrast can be spectacular.
Key Features
The foliage is the real star. Those short, fleshy, finger-like leaves create a dense carpet of blue, and because the plant stays relatively low, it’s fantastic for the front of garden beds, spilling over retaining walls or weaving between rocks and stepping stones. I particularly like planting it en masse — one plant is interesting, but a whole drift of that blue foliage can completely transform a space.
Ideal Situation
It’s also a great plant for contemporary and coastal gardens. The strong foliage colour works beautifully against concrete, gravel and stone, while its soft, spreading habit helps take the hard edge off those materials. Once established, it’s incredibly tough too, which is always a bonus.
How to Grow
Blue Chalk Sticks love full sun, and the more sun they receive, the better that blue colouring tends to be. Good drainage is absolutely essential. Being a succulent, they store moisture in their leaves and really don't appreciate sitting in wet soil, particularly through winter. If you have heavy clay, improve the drainage before planting or grow them in a raised bed or pot.
They're very drought tolerant once established and need very little feeding. Maintenance is simply a matter of trimming them back if they start wandering somewhere you don't want them. In fact, they're incredibly easy to propagate — take a cutting, allow the end to dry for a day or two and then push it into some free-draining soil. Before long you'll have another plant.
For me, Blue Chalk Sticks are all about using foliage colour as a design tool. Flowers come and go, but that beautiful powdery blue is there throughout the year, giving you contrast, texture and structure without asking for much in return. Happy gardening. 🌿