Species Spotted - Diffuse Hybrid Knapweed
purple-pink flower with green leaves and stem

Spotted - Diffuse Hybrid Knapweed

Centaurea x psammogena

Spotted-Diffuse Hybrid Knapweed (Centaurea x psammogena) is an erect biennial plant that grows approximately 1.5m in height. Its bright yellow flower heads with dark, purplish-black spots, emerge on top of long stems with small, lance-shaped leaves. This plant is native to Europe and requires full sun and well-drained soils. It has a prostrate taproot system and is commonly found in abandoned fields, roadside areas, pastures, and meadows with semi-arid nourishment. Its ability to remain persistent in dry soils is due to the presence of an extensive root system that can reach deep into the ground. Hybrid Knapweed is an aggressive invader and can outcompete other species. Managing this plant is essential to maintaining a healthy ecosystem.

Watering:

Average

Hardiness Zone:

Flowers:

Purple|Pink Flowers

Sun:

Sun, Partial Shade

Soil:

Clay, Sand, Loam

Fruits:

brown,black Fruits Ready In Summer

Leaf:

Yes

Leaf Color:

green

Growth Rate:

High

Salt Tolerant:

Yes

Invasive:

Yes

Care Level:

Medium

watering

Spotted Knapweed should be watered thoroughly every 10-14 days. To properly water, the soil should be saturated, until water begins to drain from the pot. Allow the soil to dry out in between waterings until it begins to feel dry when touched. During the summer months, it is recommended to water more frequently, as the temperatures are warmer and the plant will need more hydration. During the winter, water the plant slightly less often, but take care to ensure that the soil does not become dry and crusty. In general, err on the side of underwatering rather than overwatering.

sunlight

Spotted Knapweed (Centaurea stoebe subsp. micranthos) needs full sun in order to thrive. It grows best in well-drained soils with at least 6 hours of direct sunlight each day. During the summer months, providing plants with 8 to 12 hours of direct sunlight per day is ideal. In the winter, provide 4 to 6 hours of direct sunlight, when available. If plants are grown in part shade (under 4 hours of direct sunlight), there is a risk of stunted growth or poor flowering.

pruning

Spotted Knapweed (Centaurea stoebe subsp. micranthos) should be pruned late in the season, which is usually in the late Autumn, or early in the Spring. Prune off any dead and diseased stems or shoots first, and then remove any branches that are over-crowding the plant. Cut off any stems that are weak, crossing or growing vertically. This will allow air to circulate, encourage healthy new growth, and allow sunlight to reach the base of the plant. Pruning should be done when the plant is semi-dormant and the weather is cool and frost-free. Prune sparingly and keep any remaining cuts clean and precise.

⚠️ Perenual and its members cannot be held liable for any health issues that may arise from the information provided on the website or from using any of the plants found on the site. The information provided is intended to be used as general guidelines only.