Q: Other than using weedkiller, is there any way to get rid of scutch? It has gradually taken over a favourite flower bed filled with perennials, spring bulbs and flowering shrubs. Over the years I’ve tried digging it out, but it comes back again with a vengeance.
B Shanahan, Dublin
A: Also known as couch grass or twitch grass, scutch is a very widespread native perennial known for its vigour, resilience and ability to very quickly colonise new ground.
While it can and does reproduce via seed, the main way in which it spreads is via its wiry rhizomes, which stretch out horizontally underground from the parent plant, forever probing the soil in search of new territory.
RM Block
Left to its own devices, scutch will quickly take over, with the plant’s distinctive white rhizomes weaving themselves aggressively through the root systems of other rival plants. Fascinatingly, it also releases natural phytotoxins that suppress healthy growth of the latter.
For these reasons, it can be one of the most challenging of perennial weeds to manage. In previously uncultivated areas of the garden, covering the soil with black plastic for between 12 and 18 months before planting is generally effective. But in a mixed border like yours, the task is much more difficult.
In this case, it’s likely to have penetrated the root systems of some plants so thoroughly that you’ll need to temporarily dig these up and then meticulously remove every fragment of scutch concealed inside their root balls. In the worst-case scenario, it can sometimes infest a plant’s root ball so thoroughly that it’s better to discard it.
This sort of job is best done in late autumn, giving you the opportunity to work over the bed again several times in spring, digging out any remaining fragments of rhizome that may have resprouted underground.
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Alternatively, if your flower bed is horribly infested with scutch, consider digging up and temporarily transplanting its perennials and bulbs into another area of the garden (just make sure that you don’t accidentally bring any scutch with them when you do so). This would allow you to then repeatedly dig out any remaining stubborn patches of scutch from the bed over the course of a year, paying particular attention to areas around the root systems of established shrubs where it could be lurking.
Finally, bear in mind that scutch particularly likes a compacted, damp, heavy soil. Regular use of generous organic mulches will counter this, as well as making it easier to dig it out. Aerating the soil by forking it over will also counter compaction and help bring any remaining root systems and rhizomes to the surface, from where they should be meticulously removed to prevent them .
Best of luck.
