I've been reading up about Bonsai trees lately because I've become fascinated by the art of Bonsai. I was at the nursery looking at supplies for weed and found a few books, some trees, seeds, etc... I purchased a book to begin with hehe. So anyways, I'm finding that there is a TON of useful information in here that can apply to growing marijuana. I didn't know what those numbers by fertilizers and everything were when I first started my research on growing marijuana, and couldn't find anything on them, because I didn't know what to search for. Maybe I'm just dumb or slow, or even both, but this is for those of you who don't know what it means. There's a big section on feeding in my book and it goes in detail about the NPK ratios. In case you're wondering, the title of the book is "Pocket Bonsai" by David Prescott. It's a great book to read if you're interested in Bonsai or just want to learn more about how trees function. Bonsai is a delicate art that requires a pretty extensive knowledge of how to alter plants, and where to cut them and everything... well that's my understanding so far... only up to page 30. Back to the feeding though. On most fertilizers they will have three numbers separated by dashes in between them somewhere in the description. These numbers are ratios for Nitrogen, Phosphorous, and Potassium, or NPK. Why is Potassium a K in this group of numbers you ask? Potassium's symbol on the periodic table of elements is K. Simple as that. A very basic rule of this scale is that the higher the number is, the more concentrated that nutrient is. These numbers are on a percentage ratio, so if you see for example, (4-10-2) which are randomized numbers by the way, it means there is 4% Nitrogen, 10% Phosphorous, and 2% Potassium. The Nutrients - In Depth Nitrogen: Nitrogen is responsible for shoot development and foliage production, in short, for growth above ground. If you do not use enough Nitrogen, it can result in a plant failing to thrive, and it will have small messed up leaves and basically look like shit. If there is no Nitrogen at all, the plant may die very quickly. If too much Nitrogen is in your plants food or soil, it will cause the opposite effect; the plant will grow very rapidly with large leaves and plump shoots that are full of water and consequently, easy to snap. With just the right amount of Nitrogen, your plant will be growing quickly and vegetation time is reduced. Phosphorous: Phosphorous is essential for the development and proper functioning of a plants' roots. It is commonly used in high concentration for newly potted stock plants and commercial root crops (ginseng for example?). Phosphorous encourages the fattening of trunks (tree book) and branches which in turn prepares your plant for the heavy buds that may appear. It basically helps to establish appropriate conditions for a plant to bud. Weak growth and a pale color may be the result of an oversupply, or even lack of Phosphorous. Potassium: Potassium is probably the most important nutrient, as it aids in so many parts that are essential to a healthy plant. My book doesn't have much info about Potassium that applies to marijuana in it so I google searched it and got some nice results. Here is a quote from lkdj2003, an administrator on thctalk.com... "Having good amounts of potassium in your plants helps in having sturdy and thick stems, disease-resistance, water respiration, as well aids in photosynthesis. Potassium is also found in the whole plant. It is necessary for all activities having to do with water transportation. Potassium is necessary for all stages of growth, especially important in the development of Buds." Too little Potassium causes shitty growth; branches are weak and easily broken. The plants growth may slow down, especially during vegetation. Low amounts of Potassium means that your buds won't be as healthy or big as they could be, and they grow slower in general. Too much Potassium may cause root damage and calcium deficiencies. With just the right amount, you will have a very sturdy plant that can take any cold, dryness, or disease you throw at it. Conclusion It is very important that your plant has a balanced diet, because it is essential in proper growth, and understanding this will help you to grow healthier plants. I hope this has helped anyone reading it. Please leave some feedback if I have helped... or somehow pissed you off and failed on an epic level. Peace. P.S. I will probably come back and look at this later and realize I have made a mistake, like mixed something up or something else... I had to take a Benadryl to put myself to sleep tonight, so I'm really drowsy. If there are any errors please point them out so I can fix them, and please be mature about it. Thanks.