Take better pictures of plants
Like other photo subjects, the key is to put plants in the right “light.” Manipulating the natural light source—the sun—or even adding to it can make a big difference in accurately documenting the color and texture of a plant species. It can also increase the appeal of the finished photo.
General lighting techniques
Avoid “high noon” or mid-day light (a good rule to follow whether you’re shooting plants or people). With the sun directly overhead, you end up dealing with harsh, contrasting light that produces hard shadows and reflected hot spots.
A cloudy day is actually the best situation in which to shoot plants, because cloud cover diffuses the light. The resulting soft light might not be as dramatic, but the even light produces saturated color and an accurate rendition of the plant color and texture. That’s important for documentary work.
Shade the plant from harsh light, will allow you to shoot images on bright days as well. To diffuse the light without significantly reducing exposure, shade the plant with translucent material (rip-stop nylon, for example) stretched over a frame and placed above the plant. If the plant is small, the same effect can be achieved with a gallon-size plastic milk jug. Cut the bottom and one side out of the jug, place the jug over the plant, and shoot through the open side. The translucent plastic top and sides soften all the sunlight surrounding the plant.
Bring light to shadowed areas of the plant. It’s hard to see and even harder to photograph detail lost in the shadows. A white card often will reflect or bounce enough light to show the detail. The white card softens the reflected light, while a card covered with aluminum foil or a cookie sheet will reflect harder light but increase the light in deep shadows. If you don’t want to make your own, collapsible reflectors and diffusers are available commercially.
A strobe is another way to fill in the shadows. An off-camera flash allows more flexibility in controlling where and how much light to pump into the scene. Like the sun, a strobe aimed head-on without diffusing can cause harsh shadows, resulting in an unnatural look to the plant scene. It’s better to soften the flash or strobe light by bouncing it off a white card or covering it with a commercially available diffusing dome or filter.
When it comes to lighting, experimentation often produces the best results. So don't be afraid to try something new.