Alcea rosea. Sow Indian Spring hollyhocks seeds in full sun. This is a selection of our most popular Hollyhocks seeds, blended for planting en masse to create a beautiful cottage garden. Tall spires grow to 2m (6′) or more, with single, double, and ruffled flowers that fill in empty garden spaces with blooms in rose, pink, white, chocolate, purple, and lavender. This blend looks sensational from late spring to frost. Hollyhocks are both tall and drought tolerant, so they are a nice choice for xeriscaping. Avoid overhead watering with hollyhocks in order to delay foliar diseases, including rust and powdery mildew. These are not uncommon problems for hollyhocks, but rarely make much impact.