Centaurea alba
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Centaurea alba

Pale knapweed

Tier 2 Difficulty: medium Water: low Light: full_sun
Temperature
5–35 °C
Soil pH
6–8
Hardiness
Zone 5–9
Click count
28
Observations
20

Description

Source: leafsnap

Centaurea alba is a species of Centaurea found in the Iberian Peninsula in southern and central Spain and in a small neighbouring area in the interior of Portugal. There are three recognised subspecies, and of one subspecies, the nominate, there are furthermore three varieties. It has been called pale knapweed in English. Vernacular names which have been recorded for this herb in Castilian Spanish are calcitrapa, cardo estrellado, centaura estrellada, garbanzos del cura, siempre nueva, siempre-nueva, and trapacaballos. Other local recorded names in Spanish are abreojos, abrepuños, amargosa, amargosilla, amargoso, ardolla, arzolla, cardo abrepuños, cardo de la arzolla, marbosilla, margosilla, piropo, planta para hemorroides and raíz de la arzolla. In the Catalan language it is known as raspallera in the Valencian dialect.

Care Guide

💧 Water
☀️ Light Full sun

Pale knapweed is a sun-loving, perennial herbaceous plant that occurs in open habitats and is often found in meadows and grasslands. It prefers full sun but can also tolerate partial sun.

Ideal: Full sun
🌡️ Temperature 5–35°C

Pale knapweed can tolerate a broad range of temperatures, but its distribution may still be restricted by different combinations of moisture and heat. It does best in warm summer climates with sufficient rainfall or watering. Long periods of cloudy, rainy weather, as well as extended high temperatures, can raise the probability of Pale knapweed dying. In winter, adequate protection from cold can increase the plant’s survival rate.

Ideal temperature: 5–35°C
💨 Humidity
Humidity:
🪴 Soil 6-8
Soil pH: 6-8
🌱 Fertilizer

For Pale knapweed, a single fertilizer application in spring is typically enough, although repeated feedings can boost growth. Fertilize every month to six weeks. Fertilization improves the appearance and function of the leaves, encouraging even color and a healthy texture. It also promotes root development and nutrient uptake for sustained plant health.

🪴 Pot & Repot
✂️ Pruning
🌿 Propagating
🐛 Diseases & pets
☠️ Toxicity

Characteristics

Plant Type
Herb
Life Cycle
Perennial
Genus
Centaurea
Family
Asteraceae
Hardiness Zone
5-9
Mature Height
30 cm to 76 cm
Mature Spread
20 cm to 40 cm
Leaf Color
Gray, Light Gray
Leaf Type
Deciduous
Flower Color
White
Flower Size
3.05 cm to 5.08 cm
Bloom Time
Summer
Planting Time
Autumn, Winter
Harvest Time
Late summer, Early fall, Mid fall

Tags (6)

Common Names (1)

en Pale knapweed