as far as fertilizers go, it depends on what stage of plant life that you are in. there are 3 major (macro) nutrients needed by plants. they are nitrogen (N), phosphorus (P) and potassium (K). the three numbers you see on a box/bottle of fert are listed as such: N-P-K. this is the amounts of each in the product.

if you are in the vegatative phase then you need something high in nitrogen and potassium and low in phosphorus.

if you are in the flowering phase then you need something high in phosphorus and lower in nitrogen and potassium.

there are also calcium (Ca), sulphur (S) and magnesium (Mg). these are called micro nutrients. they usually are contained in most plant foods but check the label.

and then you have what are called trace elements, also usually found in the food of your choice but not always. the trace elements are boron (B), copper (Cu), molybdenum (Mo), zinc (Zn), iron (Fe) and maganese (Mn).

there you have it.

-shake