Perhaps the best thing about growing marijuana indoors is that you have increased control over virtually every aspect of the growing process. While the seeds themselves won’t need light initially, they will certainly need some light when they produce visible sprouts. Light acts as their sustenance at this period of time and it can affect the plants later on in life if they are deprived of the valuable light they require. This assumes, of course, that the soil, nutrient quality, and watering regimen are all adequate as well.

At this delicate stage, the lights should be somewhat close to the marijuana plants. In fact, dropping them down to about four inches away from the soil is ideal is you use fluorescent lights. The light cycle should also be relatively rigid at around 16 to 18 hours of light per day. This will be the light cycle for a majority of the plant’s life, but it can be hard to maintain a reliable schedule. To remedy this, you can purchase an automatic timer which only costs about $8 and will let you focus on other things.

 

Lights close to plants Electronic Timer Small plants under fluorescents

 

Depending on the particular strain, some plants could stand to use a more intensive light regimen. Cannabis really tends to absorb light voraciously because it is a high-energy plant. Some marijuana growers have been known to expose their plants to a light cycle in which the plants received a full 24 hours of light. Most growers won’t have to go to those extremes, but you may need to increase the light cycle to over 18 hours at some point if you want to improve growth. Of course, the automatic light timer can make this considerably easier, and some lights actually come installed with a timer. As the marijuana plant ages and starts to grow, the lights should still remain as close to the leaves as possible without causing damage to them. The instructions on the lights might tell you to keep them at a certain distance from the plants, but cannabis requires a lot of light energy to thrive. In fact, with lower output bulbs, you can place the lights about 2 to 4 inches away from the tops of the leaves. For higher output bulbs, you can place them about 4 to 6 inches from the top of the leaves.