Light And Water Question

Given a 400w Metal Hallide light, 5 plants (2 Sour Diesel 3 Bubbleberry Kush) in separate 5 gallon containers filled with Fox Farm Ocean Forest soil, all plants having an average height of 6 inches, and all in vegetation; I have three questions:
1. How far away should the light be from the actual plants?
2. How often should one water the plants?
3. How much water should one give the plants while watering? (does the size of the container, amount of light or size the plant affect this amount)

Any help would be appreciated!

 

1. Depends on your light! Cool tubes and air cooled reflectors can get closer without too much heat. The only way to know for sure is to check by using your hand. Hold your hand out flat, at the top level of the plants. After about a minute you should feel warmth from the light, not high heat, just warmth. Adjust the lights till it feels right!

2. Whenever the soil dries out a bit! Sounds simple, but overwatering (and overfeeding) kill more plants for beginners than anything (except maybe lack of preperation). Cannabis likes to "dry out" a little in between waterings, so here's what you do. Slowly (a bit at a time) add water untill some comes out the drain holes. Now it is saturated - pick it up, feel how heavy it is - get used to the "heft" of a saturated plant. Check the weight daily. As a few days pass, the containers will get lighter. At some point the pots will become very light and the plants will show signs of wilting - get used to the "heft" of a wilted plant too, because that's when you know you have gone too far! The trick is to water them well before they wilt, but while the pot is light. You just have to get the feel of it!

3. Yes, all those things affect the amount of water, especially the size of the plant. A big plant, in the hottest part of summer, may need water almost everyday. But the method is always the same - feel the weight of the pot so you know it has dried out some. Add water slowly and evenly (a bit at a time) untill some trickles out the drain holes. Relative humidity and other factors make it impossible to say how much water is the "right" amount for your plants - you just have to get the feel of it!

 

Hey THCammo good info but I am confused on what you mean by wilting? IS that white discoloration of the leaves of just the leaves turning yellow or maybe neither? Also confused on more lingo- the word heft- I am not familiar with, sorry for the unclarity but if you could help it would sum up alot of things for me and my plants!@

 

Let me fill in here for my bud

Wilting - caused by lack of water - is when the plants leaves droop (almost lifeless) from the bottom of the plant and will progress upward.

Leaves yellowing, particularily from the bottom fan leaves progressing upwards, is generally due to a lack of nitrogen. However, without a picture it is a guess. Not sure about white discoloration - possibly powdery mildew (outside plants get this at times).