Of the survivors, 21 are moth mullein, one is another type of Verbascum and the last a variety of the Malva species that had not sprouted since 1899.
From the time.com
Watch for the black, yellow and white caterpillars of the mullein moth on your verbascums.
From the independent.co.uk
The worst are the progeny of the cabbage white butterfly and the similarly-coloured caterpillars of the mullein moth, at their busiest in June and July.