A T8 bulb is a florescent light bulb used for indoor growing of plants. Every florescent bulb is classified according to its diameter, which is measured in eighths of an inch. A T8 bulb is a common florescent bulb that is 8/8 of an inch (1 inch) across.
Choosing a Florescent Bulb
Plants that grow indoors need light. Florescent bulbs have long been used as an inexpensive and energy-efficient way to provide this light. Plants need adequate amounts of blue and red light in order to go through photosynthesis, the process that plants use to create food. A good indoor grow light will have enough lumens in the right color spectrum to provide a plant with the light it needs.
Light Levels of T8 Bulbs
The T8 or slimline florescent tube has now become popular, although the T12 is still the main florescent available. Slimline tubes are smaller and not quite as bright as the T12 tubes.
If you want to use the smaller T8 tube to grow plants, it is best to find a high output or very high output tube. This will ensure that the tube has the maximum amount of light for its size. Choose a 4-foot-long tube if possible, since this gives out the most light per watt of energy use.
Uses for T8 Bulbs
T8 bulbs provide adequate levels of light to start new seeds, as long as they are placed close to the seeds. If the light levels are low and the bulbs are too far away from the seeds, the seedlings will become leggy. This means that the stem will be too long and the seedlings will collapse when transplanted.
The T8 bulbs are not always adequate for larger household plants. If the plant requires very little light and does not acquire enough light from natural sources, the T8 bulb can be a good supplemental light source.