Great Globe Thistle

This is a glandular, woolly perennial herbaceous plant which reaches on average 50–100 centimetres (20–39 in) of height, with a maximum of two metres.
Its erect, branching, gray, slightly wrinkled and hairy stems bear the occasional large, soft, sharply toothed, sharp-lobed pointed green leaves. They are sticky hairy above, and white woolly below.
Atop each stem is an almost perfectly spherical inflorescence up to 6 cm in diameter, packed with white or blue-gray disc florets. It flowers from June until September. (Wikipedia)