You must understand that choosing a variety is quite important when it comes to growing marijuana. The quantity and yields of the plants which are grown under those artificial lights would have to depend on the variety of the seed or if the plants are grown from the clones or seeds. Moreover, you may consider how many days to grow the plants are being put into flowering and optimization of the climatic conditions in the grow-room.
Surely, there has been an increase in the growing of cannabis indoors. If done right, such would produce fantastic quality that is often a lot better than being sold on the streets. You should also know that growing cannabis indoors really depend on using the powerful artificial lights to be able to replicate the effect of the sun. These lights would take hundreds of Watts of electricity to operate and are usually HPS lights but the other kinds of lights are also great when it comes to growing the marijuana buds.
The cannabis loves light and that successful indoor grower would try to deliver so much light too. You need to have 250 watts/m2 being the minimum starting point and aim for two to three times that level when you can. When there is more light, then there can be denser as well as bigger buds and you will get to enjoy bigger yields too. You have to keep in mind that the successful indoor grower should use high light to ensure that the plants get to close to the light maximizing the intensity to be able to reach the leaves as well as buds of the plants. For such personal recreational or medical grower, then such growing area of one to two square meters may have 600W or 400W HPS lamp.
The indoor cannabis grower has to be careful that the plant will not grow very near the hot light and cause damage to itself. Test the light at the back of your hand if it feels cools, since this would also be the same for the plants too. For such 400W lamp, growers may not want the plants to grow 40 to 50 cm of the bulb. Those cannabis plants may be bent over and tied when they get too tall. Some of those indoor growers would train the plants in this manner to get much of the plant close to that high intensity light.
Some strains would really respond better through pinching out the growing tip of such plant after the fourth or the fifth leaf pair. This would result to plants which are smaller and bushy with no dominant main growth stem and they are preferred for those smaller growrooms.