Festuca 'Boulder Blue'

Festuca 'Boulder Blue': A Steel-Blue Hedgehog for Hot, Dry Spots

'Boulder Blue' looks exactly like its name: a dense dome of steel-blue needles, sitting in the border like a smooth rock that decided to grow hair. LOW MAINTENANCE, HIGH CHILL.

Plant Characteristics:

• Botanical Name: Festuca glauca 'Boulder Blue'
• Common Name: Blue Fescue
• Height: 20–30 cm (8–12 in)
• Spread: 25–30 cm (10–12 in)
• Flowers: Slender spikes that ripen to tan seed heads
• Bloom Time: Early to midsummer (June to July)
• Foliage: Very fine, needle-like, steel-blue blades in a dense dome. Holds its colour well into fall and stays evergreen in mild winters.

Where to Plant: Its tight, rounded shape makes it a natural edger along paths and patios. It also works massed as a small-scale groundcover spaced about 30 cm apart, tucked between stones in a rock garden, or planted in gravel and containers. The colour is bluest in full sun.

Companion Plants: Dianthus Pretty Poppers® 'Double Bubble' sits at the same low height with pink flowers from June to September. Sanguisorba 'Pink Tanna' adds pink bottlebrush flowers at 60 to 90 cm over the same months. At the back, Echinops ritro grows 90 to 120 cm with round blue globes from July to September, echoing the fescue's colour. Plant them in sun or part sun.

Plant Care: Plant in full sun in light, well-drained soil. Sandy or gravelly ground suits it best. It will shrug off dry spells once established, but wet, heavy clay over winter can rot the crown, so improve drainage before planting. Water through the first season, then only in long dry stretches. Don't fertilize. Lean soil keeps the clump compact and the colour strong. Some afternoon shade is fine, but too much shade turns the blue dull and the clump loose. In early spring, run your fingers or a rake through the clump to pull out dead blades. Clip off the seed heads once they brown if you like a neater look. Divide every few years when the centre opens up.

History: Blue fescue, Festuca glauca, comes from dry, rocky places in southern Europe, and its species name refers to the waxy, blue-grey coating on its leaves. 'Boulder Blue' is one of the compact, steel-blue forms selected for small, dry, sunny spaces.

Final Thoughts: Line a sunny path with a row of them and call it hardscaping. THE ONLY BOULDER YOU CAN LIFT WITH ONE HAND.