The spur flower (Centranthus), with its mainly white, red and pink subspecies, has become native to many Central European gardens due to its rather undemanding care. The plant, which is actually quite winter-hardy, can also die in some locations without freezing temperatures or after a certain lifespan.
Is the spur flower hardy?
The spur flower (Centranthus) is hardy and can withstand temperatures down to minus 20 degrees Celsius. It grows perennially, but is rather short-lived. However, through self-sowing, the plant population in the garden can constantly rejuvenate.
Sun-hungry flowering plant with Mediterranean origin
The various subspecies of the spur flower actually come from areas in the Mediterranean regions, but were already cultivated in many gardens of monasteries and castles in the Middle Ages. The plant, which often grows in barren rock crevices in its area of origin, is generally hardy even in Central Europe without winter protection. Specialist retailers usually state that cultivated varieties have winter hardiness down to minus 20 degrees, as the plants overwinter in the ground anyway and sprout again every year. However, the perennial plant is rather short-lived, which is why individual specimens may die after a few years of life.
Self-sowing ensures regularly rejuvenated plants in the garden
Since the subspecies of the Centranthus genus generally self-seed relatively strongly, the short lifespan of some specimens is actually not a problem. Depending on the time of sowing (with Centranthus, two flowering phases are possible by cutting after the first flowering), the seeds germinate either in autumn or in spring. If you allow plants to self-sow in the garden, you will not only benefit from the permanent rejuvenation of the plant population. It can also be quite attractive in cottage gardens and natural perennial beds if the spur flower specimens find a suitable location themselves.
Don't choose the time for sowing too late
If the seeds are specifically sown for a first flower in the following year, the spur flower should be sown in September at the latest. Then the young plants can overwinter sufficiently strengthened and start the new garden season already strengthened. If possible, sow the seeds directly in the bed, as plants grown in pots may otherwise require frost protection due to their exposure to the winter cold.
Tip
If the plant of the Centranthus genus in your garden has difficulty getting through the winter or not at all, even without very pronounced sub-zero temperatures, you should take a closer look at the soil at the location. Since the spur flower can only grow well on well-drained soil, compacted, clayey soil and waterlogging are often the reason for stunted growth or death over the winter.