perform the most photosynthesis. I think this because even though the blue light is a very high energy light, after a certain point the plant will not be able to. Plants need light energy to make the chemical energy needed to create carbohydrates. Increasing the light intensity will boost the speed of photosynthesis. Photosynthetic Efficiencies of LEDs: Results of Short Term Exposure to LED Lights. when testing the black light for its effect on photosynthesis. Photosynthesis is a process in which light energy is used to produce sugar and other organic compounds. Pigments for Photosynthesis Photosynthesis in plants is dependent upon capturing light energy in the pigment chlorophyll, and in particular chlorophyll a. Lab 2: Photosynthesis (The Light Reactions) 127 4. After 15 minutes open the light boxes and carefully place 300 µl of Terbicel in each tube. The Effect of Black Light on Plants. Chlorophyll and other photosynthetic pigments (called phytopigments) have distinct spectra that show what wavelengths of light. Black Light & Plant Growth. Plants need light to grow. Light can be measured on the light scale that ranges from red to blue. Young plants need lights in the blue. Effect of Different Colored Lights on Photosynthesis. Anastasia Rodionova. All these pigments absorb light and possibly utilize the light energy in photosynthesis. Why are Leaves not Black? Light must be absorbed for nutrients to be created by Photosynthesis. So why reflect the green and waste the whole middle part of the spectrum?.