Mammoth sunflowers, also known as Russian Mammoth sunflowers, are indeed a popular variety of sunflowers known for their impressive height and large flower heads. When it comes to their blooming behavior, most Russian Mammoth sunflowers typically produce only one main bloom per plant.
Once the sunflower plant has reached its full maturity and the flower head has fully bloomed, the petals of the flower will eventually start to wither and die back. This is a natural process and an indication that the plant has completed its flowering stage. At this point, you have a couple of options on what to do with the plant.
If you are growing the sunflowers for their seeds, you can leave the plant standing to allow the flower head to fully mature and dry out. As the petals die back, the center of the flower head will start to turn brown and become more prominent. This is where the sunflower seeds are located. Once the flower head has dried completely and the seeds have fully developed, you can harvest them for various purposes, such as eating, bird food, or planting for future growth.
On the other hand, if you are growing the sunflowers primarily for their ornamental value and do not have an interest in harvesting the seeds, you can remove the plant after the petals start to die back. This is a personal choice and can be done for aesthetic reasons or to make room for other plants in your garden.
When removing the plant, it is recommended to cut it at the base using gardening shears or a sharp knife. Be careful not to damage any surrounding plants or disturb the soil too much. After removing the sunflower plant, you can dispose of it in your compost pile or green waste bin.
It’s important to note that while most Russian Mammoth sunflowers only produce one main bloom, there can be instances where secondary or smaller blooms may appear on the same plant. These secondary blooms are not as large or significant as the main bloom but can still add some additional beauty to the plant.
Mammoth sunflowers typically only bloom once, with the main flower head being the most prominent and significant bloom. After the petals start to die back, you can choose to either harvest the seeds or remove the plant depending on your preferences and purposes for growing the sunflowers.