Delphinium worms can cause quick and thorough damage to your delphinium.
These beauties were 8’ tall last year and I was a bit lazy in the fall, so I didn’t cut them down. I leave the vast majority of the perennials in the demo-garden standing. It adds winter interest and it provides some winter habitat for some biodiversity.
It allows insects to overwinter too, both the beneficial ones AND the rascals like these delphinium worms. That’s just the reality of wild spaces.
I should have cut them down to about 4-6” tall this spring when they sprouted and disposed of the clippings. But I was busy with other priorities so the worms enjoyed a couple months of smorgasbord and egg laying.
The larvae are clearly visible in the cut, hollow tube of the stem.
The plant is now trimmed and unlikely to regain its beauty this season but it will bounce back for next year.
That’s just the way it goes sometimes in a garden.