Zum „Tag des Unkrauts“ am 28. März werben Fachleute aus deutschen und österreichischen Einrichtungen für einen grundsätzlichen Wandel im Umgang mit Wildpflanzen. Sie verweisen darauf, dass viele beliebte Zierpflanzen ökologisch wenig beitragen, während sogenannte Unkräuter für Insekten, Vögel und andere Tiere wichtig sind.

Wildpflanzen sind für Tiere entscheidend

Fachleute betonen, dass Brennnesseln, Klee, Löwenzahn und Beifuß wichtige Nahrungs- und Lebensräume bieten.

Zierpflanzen liefern oft kaum Nahrung

Hortensien, Forsythien und Kirschlorbeer gelten nach Einschätzung der Experten als ökologisch weitgehend wertlos.

Pflege im Herbst kann Insekten schaden

Wer verblühte Stängel abschneidet und entsorgt, zerstört nach Angaben der Experten auch Puppen und Überwinterungsorte.

On „Weed Day,“ marked annually on March 28, experts from German and Austrian institutions called for a fundamental rethink of how gardeners perceive and treat wild plants, arguing that common ornamental garden plants are ecologically worthless while so-called weeds are vital to the survival of insects, birds, and other wildlife. Bettina de la Chevallerie, managing director of the Deutsche Gartenbau-Gesellschaft 1822 (DGG 1822), told reporters that cultivated ornamental perennials and exotic shrubs frequently offer little or no food for native insects. She pointed to hydrangeas, forsythias, and cherry laurel as plants that may appear attractive but are, in her words, ecologically completely worthless because they provide little or no nectar or pollen. The mass planting of such species in private gardens creates what experts described as a hunger problem for insects. Margarita Hartlieb from the University of Vienna added that the derogatory label "weed" misleads gardeners into treating ecologically essential plants as dispensable nuisances.

Brennnesseln und Löwenzahn halten Schmetterlingsarten am Leben Wild plants including nettles, clover, dandelion, and mugwort, routinely pulled from gardens as unwanted growth, are in fact critical food and habitat sources for a wide range of species. Butterflies such as the peacock butterfly, small tortoiseshell, map butterfly, and red admiral lay their eggs exclusively on nettles, because their caterpillars feed solely on nettle leaves. Without nettles in gardens, these species cannot complete their life cycle. De la Chevallerie proposed replacing the word "weed" with "wildflowers" or "companion plants" to shift public perception toward the ecological role these plants play. „Auf jeden Fall sollte das Wort Unkraut gestrichen werden” — Bettina de la Chevallerie via Der Tagesspiegel The timing of garden maintenance also matters: removing and discarding faded plant stems in autumn destroys the pupae of butterflies attached to those stems, eliminating the next spring generation before it can hatch. Wild bees and other insects similarly rely on withered plant stems as overwintering sites, meaning autumn tidying can eliminate entire local populations.

Gepflegte Rasenflächen als fast tote Ökosysteme beschrieben Sophie Lokatis, a nature and species conservation expert at the Deutsche Wildtier Stiftung, described neatly trimmed lawns as environments that offer almost no ecological value. Many gardeners invest heavily in bird feeders and birdhouses during winter, but Lokatis argued that garden design is far more consequential for wildlife than supplementary feeding. „Solche Flächen sind fast tot” — Sophie Lokatis via DIE WELT She noted that the number and diversity of songbirds have declined in parallel with the decline in insects over recent decades, with many bird species depending on insects as food, particularly when raising chicks. A further trend compounding the problem is the growing fashion for so-called grid-mesh fences with woven plastic slats, which Lokatis said offer neither nesting sites nor food in the form of berries or insects, while also releasing environmental toxins as the plastics degrade. Hedgehogs, increasingly rare in rural areas due to intensified agriculture, are now concentrated in gardens and urban green spaces, where they too depend on insects and shrubs for food and shelter.

Experten raten, Stängel über den Winter stehen zu lassen The experts' collective message on Weed Day centered on a shift away from the aesthetic ideal of the perfectly ordered garden toward designs that support biodiversity. Leaving wild plants to grow, allowing plant stems to remain standing through winter, and replacing ecologically barren ornamental shrubs with native species were all presented as practical steps available to individual gardeners. Weed Day provided a platform for conservationists and horticultural organizations to reach hobby gardeners who may be unaware that their planting choices affect local insect and bird populations. The framing of the debate around language — specifically the loaded term "weed" — reflected a broader argument that cultural attitudes toward tidiness and order in gardens carry measurable ecological consequences. Hartlieb's observation that the word "weed" implies dispensability was echoed by de la Chevallerie's call for a linguistic and conceptual shift in how gardeners relate to the plants growing uninvited in their plots.

The decline of insect populations in Central Europe has been documented over several decades and is widely linked to changes in land use, including agricultural intensification and the spread of ecologically simplified private gardens. Wild bee diversity is a particular concern: according to the Deutsche Wildtier Stiftung, 604 wild bee species are currently recorded in Germany. Research involving Sophie Lokatis, conducted in collaboration with the Freie Universität Berlin, found up to forty times more wild bees, beetles, and other winged insects in areas with meadow grasses and flowers compared to short-mown lawns.

Mentioned People

  • Bettina de la Chevallerie — Dyrektorka zarządzająca Niemieckiego Towarzystwa Ogrodniczego 1822 (DGG 1822)
  • Sophie Lokatis — Ekspertka ds. ochrony przyrody i gatunków w Niemieckiej Fundacji Ochrony Dzikich Zwierząt
  • Margarita Hartlieb — Ekspertka z Uniwersytetu Wiedeńskiego

Sources: 4 articles