Shop our selection of heirloom and organic broccoli seeds. Broccoli is remarkably nutritious; containing many phytonutrients, including thiocyanates, indoles, sulforaphane, isothiocyanates, and flavonoid. Broccoli is a great source of vitamin C and vitamin K. Choose broccoli seed such as Waltham 29, De Ciccio and Spring Raab.