Color is the single most important aspect to consider when photographing landscapes. A strong color such as red helps to create great images that stand out to a viewer. Subtle color harmonies can also yield great pictures, such as cool hues from a foggy seascape.
Clouds make the difference when photographing landscapes, preferably ones that are near the horizon and above your main target. During the prime lighting of sunrise and sunset clouds turn an array of different colors creating a more dramatic and dynamic image. Clouds can also help make photographing at midday possible by diffusing light from the sun.
Calm atmospheres are great for capturing detail. The slow shutter speed used for landscapes makes shooting difficult in windy situations, creating blurry images. Still moments allow you to capture all the detail of the surrounding area such as wildflowers, grasses, pools of water, etc. The best time of day to find these ideal conditions is 30 minutes before and after sunrise.
Falling snow, fog, mist and haze give landscapes a moody energy and give added features to the landscape.
North and south camera angles at sunrise or sunset, depending on your location, will yield a wonderful side lighting upon your landscape. This brings out detail and color more effectively than other lighting angles.
When you find your target landscape check the eastern and western horizons to make sure they are clear of light-obstructing landforms. The time of day is important here, if the eastern horizon is clear take photos in the early morning. If the western horizon is open shoot at sunset.
When photographing landscapes don't forget the small details. Utilize features like rock formations or plants and place them in the foreground, this adds depth and gives scale to the scene.
Knowing when the moon will be present in the sky can add an extra element to your landscape. Capturing the sun in an image creates problems with contrast and will require a lot of editing to create a satisfying image.
Still waters can create amazing images by allowing you to reflect landscapes onto water. Capturing these reflections requires you to have the right angle and sometimes means getting into the water, so be prepared with waders or a swimsuit.
Shooting landscapes with animals is a rarity. It is best to concentrate on the landscape and pray an animal waltzes into your scene. The best opportunities arise when you are shooting wildlife. Take a moment and a few steps back to capture the whole scene.
The final thing to remember is to keep human artifacts out of the image. These features can ruin a beautiful scene, but shooting in national parks and forests can limit this problem since they have less human influence than most places.