Nutrient availability is one of the factors that can encourage growth in sunflowers, Seiler says. Plus the giant gray stripe variety, which is what the Andersons planted, is one that can grow ...

Question: I planted sunflowers with my children this past ... single-flower bearing varieties such as 'Mammoth Russian' and 'Giant Grey Stripe.' The seed packets sold in the spring for planting ...

The mammoth grey stripe sunflowers – among the largest of the sunflower varieties – started blooming July 6, the day the arboretum on the north side of the Cal State Fullerton campus opened ...