Hollyhock Chater's Double Mix Alcea Rosea is a hardy biennial flowering plant. Hollyhock Chater's Double Mix seeds can be started directly outdoors or indoors and in pots in a cold frame. Hollyhock Chater's Double Mix variety produces fully-double scarlet, pink, white, purple, brown and yellow flowers that are 3-5 inches across and densely clustered together on the sturdy flower spikes. Hollyhock flowers grow on rigid, towering spikes or spires which typically reach a height of 5-6 feet tall, and the foliage features large, heart-shaped, rough lower leaves which become progressively smaller toward the top of the spire. Alcea Rosea are base branching and bloom from May to October attracting hummingbirds and butterflies.