Devon, United Kingdom

What has laid its eggs on my Sweet Rocket? It now has tiny caterpillars encased in silky thread on every flower bud - or it did have until I spotted them today. This is one of my favourite plants and now looks quite damaged, which is so disappointing. I should have kept a closer watch but it hasn't happened before. i did get three more of them but the leaves are purpley coloured and oval, whereas the old one has longer light green leaves, so I'm not sure what they will be like or whether they will be as gorgeous.
Is there anything I can use to make sure the little critters have all gone? Chemicals are a no no here but on this occasion I'm prepared to use them. Sorry no photo as my camera needs fixing.

• 10 Apr, 2010