Centaurea Ragusina

Centaurea ragusina is a silvery, low-growing mound that has adapted to heat, drought, and poor soils.

If you’re looking for a filler plant that can be planted alongside agaves and cacti in xeriscape and Mediterranean gardens, this would be a great choice.

Botanical name: Centaurea ragusina

Other names: Knapweed, ragusina knapweed, silver knapweed

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Centaurea ragusina is a low-growing evergreen groundcover that reaches about 1-2 feet in height and 1-2 feet in width, with a mounding growth habit.

The beautiful, silvery, light green leaves are covered in tiny white hairs. The velvety leaves have multiple lobes that create distinct geometric patterns.

Centaurea ragusina is part of the sunflower family. From spring to summer, it blooms showy, bright yellow flowers that contrast with the muted-colored leaves.

Centaurea ragusina, often called “silver knapweed,” is a low-maintenance perennial that performs well in areas that get cold winters and very hot summers. Can tolerate temperatures from 10 degrees to 120 degrees.

Tolerant of saltwater in coastal areas.

Tolerant of nutrient-devoid soils and drought. It can be planted alongside desert plants such as cacti.

Compact growth that fills out the area it was planted in. It can be used as a filler plant or border edging.

Silvery-green leaves are evergreen. The spring-to-summer bloom season adds a pop of yellow to the scenery.

Centaurea ragusina is from coastal rocky areas in Croatia.

Soil: Loose, well-draining soil. Does not require fertilizer.

Temperature: Can withstand temperatures down to 10 degrees to 120 degrees for a short period of time.

Water: Occasional, deep watering. Allow the soil to completely dry out between waterings. Either use a moisture meter or stick your finger through the soil to gauge the moisture level. It’s better to err on the side of underwatering than overwatering.

Sun: Full sun. Partial shade in the Palm Springs region is ok.

Pests: Centaurea ragusina has minimal pests. Fungal diseases include root rot, dry rot, and harsh weather conditions.

Signs of overwatering: Drooping, squishy texture, browning leaves

Signs of too little water: Shriveled leaves, leaf fall, browning leaves

Signs of too much sun: Burning, fading leaves

Signs of too little sun: Etiolation, discoloration

To propagate Centaurea ragusina, divide up the clumps and relocate them.

How much does a Centaurea Ragusina cost?

At our nursery, Centaurea ragusina costs $25 for a 5-gallon container.

Prices are subject to change. Please contact us for the most up-to-date information on pricing. We may have larger sizes available. We provide installation services locally at a separate cost.

Should I plan Centaurea ragusina in full or partial sun?

In temperate regions such as in San Diego or Santa Barbara, plant in full sun. For hot desert regions such as Palm Springs or Phoenix, partial sun is best.

Is centaurea ragusina drought tolerant?

Yes. Its velvety hairs on its leaves help it to retain moisture and its light minty color help it from absorbing too much sun.