The two most basic things every plant needs are water and light. For the indoor grower it is very important to know what type of light to give their plant. Without knowledge in this area your harvest will be very disappointing. While hard to crack, once you gain understanding in lighting you will be on the fast track to growing success. In order to get there you are going to need to understand both old and new concepts.

When looking at indoor grow lighting the first area of understanding needed is of the Kelvin Scale. The Kelvin Scale (K) is used to rate the temperature of light. Cooler colors such as blue and white have a higher K of 5000+ while warmer colors such as orange and red have a lower K such as 2500-3500K. A cool 6500K is perfect for vegetative growth of a plant. As far as budding goes it is best to use 2700k, a much warmer frequency. Many growers suggest using a little 6500k while budding and a little 2700k while growing to cover the full spectrum.

The next bit of needed knowledge is in regards to Lumens. Lumens are used to measure the strength of light as viewed by the eye. Lumens are the best way way to measure the power and penetration of a bulb. Different bulbs have a pretty wide range of lumens. As far as compact fluorescent bulbs go a 100 watt equivalent will produce 1,500-1,900 lumens. A High Pressure Sodium bulb is much more powerful and can produce around 50,000 lumens with a 400 watt bulb. Lumens are very very important to your plant during flowering and will be a huge determining factor in the density of buds.

CFL bulbs have burst onto the scene and have many growers rethinking their light setup. CFL bulbs can be bought for very little money at almost any grocery store and use very little energy. A few 6500K CFL bulbs can be more than enough to get a plant through the vegetative cycle. However, though you can grow a large plant with CFLs, there are questions about their ability to produce bud. Many growers experience great vegetative growth with CFLs but are disappointed that the buds produced are often light and fluffy compared to the highly sought after dense buds which are more common when using a high pressure sodium bulb. The reason for this is thought to be that the lower lumens of the CFL bulbs lack the penetration required to produce dense buds.

Weather it is with CFL, high pressure sodium, or metal halide you should choose your bulbs carefully. Growing weed indoors requires that you do so.