Three-cornered garlic, montbretia and Spanish bluebell: the minor invasives that bother gardeners most
Not on Schedule 9, not catastrophic — but they take over and they are surprisingly hard to remove.
These three species are not on Schedule 9 of the Wildlife and Countryside Act, but they take over a domestic garden faster than almost anything else and they are not easy to remove once established.
Three-cornered garlic (Allium triquetrum)
Triangular-stemmed white-flowered allium that spreads by bulb division and seed. Dig every bulb out — leaving any behind guarantees re-establishment. Bulbs go in the general waste, not the compost.
Montbretia (Crocosmia x crocosmiiflora)
Cheerful orange flowers in late summer, but the corm chains run for metres and produce a dozen new plants from a single dropped corm. Sieve the soil.
Spanish bluebell (Hyacinthoides hispanica)
The big-leafed, upright, scentless garden bluebell that hybridises with our native species and is now the dominant bluebell across most of urban Britain. If you have native bluebells in nearby woodland, removing your Spanish bluebell helps.
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Reviews the technical, legal and lender statements in this article.
What this page can't tell you
- Guidance is general. Identification, treatment choice and timescales can only be confirmed by a site visit — photographs alone are indicative.
- Lender and insurer requirements vary by institution and change over time. We state what is typically accepted, not what any named lender will accept on your case.
- Guarantee (IBG) eligibility depends on the plan chosen, the survey findings and the underwriter's acceptance. It is not automatic.
- Legal points summarise published law and guidance current at the review date. They are not legal advice.
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