Q.Do I cut back spikes on popcorn cassia once it has finished blossoming
Do spikes continue to bloom or should I just trim them off
Regular dead-heading keeps many plants blooming, especially annuals. The goal of an annual plant is to set seed. If you frustrate that goal by trimming off spent bloom stems, no seed is formed and the plant sends up more flowers in another attempt. Toward the end of summer, you may wish to collect seed for next year. Remember that many hybrid flowers do not "come true from seed"; in other words, your plant from collected seed may have different characteristics than the current plant.