Uplighting fixtures come in a variety of sizes and wattages. As a rule of thumb, the larger the fixture the more wattage or brightness it gives off. Low voltage spotlights can be as bright as 50 watts and that is usually sufficient to high light a tree 30 feet tall. Low voltage fixtures require a transformer to convert the voltage down to 12 volts. Fixtures mount on a 6 inch stake and low voltage multi strand wire is used. The most common wire size is 12 gauge, with thicker wire being used for longer runs. We recommend leaving 2 feet of wire buried at each spot light so the fixture can be moved as the plant materials grow and mature. 120 volt spot lights are more permanent once installed and require a permapost when installing in the ground. Both of these fixtures should be placed within a plant bed so as to not be damaged by a lawn mower or weed whacker.