Glen Payne, Beaufort County Urban Horticulture Agent and Master Gardener Coordinator
Sunny summer weather is something that makes every day a little brighter than the one before. So, we take the rainy days with the sunshine, stillness with the pleasant breezes, dryness with lots of humidity that can help us with our skin complexion during the humid summer months along the coast of South Carolina. Plants are subject to the same outside conditions, and they thrive with the three things that plants need…sunlight, water, & air. Different species of plants need different amounts of sunlight while other plants prefer shade. One thing that is constant is that all plants do require sunlight to survive. Sunlight drives photosynthesis by converting light energy, water, & carbon dioxide into chemical energy for plant growth.
Long day plants such as cacti, vegetables and fruits require 12 – 16 hours of sunlight in order to flower and perform best doing the sunny days of summer. Certain plants even have direct sunlight requirements to perform their best, for example 6 hrs. of direct sunlight is required for tomatoes, peppers https://hgic.clemson.edu/factsheet/pepper/ , basil, & zinnias https://hgic.clemson.edu/factsheet/how-to-grow-zinnias-the-best-varieties-care-tips/. Keep in mind that the uninterrupted dark period (less than 10 hrs.) is critical and when plants period of darkness is interrupted will affect their flower production if light is introduced only for a few minutes. Plants like the sunflower and black- eyed Susans, fruits like peaches https://hgic.clemson.edu/peaches-the-story-of-south-carolinas-non-native-state-fruit/, blueberries, & blackberries may not yield as much fruit if their long period of light requirements are not met.
Short day plants require much less uninterrupted periods of sunlight and will perform at their peak with 8- 12 hours of bright sunlight. They do require periods of much longer uninterrupted darkness and typically in coastal South Carolina plants are the poinsettia https://www.poinsettclub.org/Club_Heritage/Joel_Poinsett , chrysanthemums, and Christmas cactus that are short day plants. Keep in mind that interrupted darkness with the introduction of a flashlight, small room light, or too long of sunlight exposure can interrupt the chemical signals for plant flowering. And with all that said sunlight is still required by plants in the winter months to perform at peak flower production.
So, know that even if the rain is coming down this summer, behind the clouds the sun still comes out and is shining bright and soon, we will be able to see it, feel it, grow wonderful plants in it, and enjoy the bountiful harvest that has been created thanks to it. The sunny side of summer is needed by people & plants and is here now to enjoy.
