Here's a BASIC organic soil recipe that will produce damn fine results. Props to MoHo for originally posting...beginners give this a whirl if the "supersoils" seem intimidating or too expensive etc...
Base Mix:50% good potting soil (Black Gold,
OF, Roots Organics, etc.)
30% perlite (or rice hulls, if you can find them)
20% worm castings or quality compost
To that you can add all kinds of goodies, OR you can keep it simple as hell and just add:
1-2 TBSP dolomite lime per gallon of soil and
A dry fertilizer product (like Happy Frog 5-5-5 or Peace of Mind 5-5-5, or the Espoma Organic Traditions All-Purpose one, or Earth Juice's "Rainbow Mix", etc.)
Most of those dry fert brands ^ are like $7-15 per bag and you can just follow the application rates on the packages. It's usually like 1/4 cup per container. And yes, you can get all the way through flower with an "all-purpose" balanced fertilizer. In organic soil, you supply the soil with all the nutrients a plant needs, then feed the microbes and fungi in the soil with compost tea, and watch as the plants and the soil microbes "communicate" with one another... the plant will "ask" (via root exudates) the soil microbes for exactly what it needs, when it needs it... and will leave the rest behind in the soil. This is what most people don't get about organic soil growing. There is no need for manipulating N-P-K ratios to any significant degree. You aren't force-feeding your plants; you are just sliding their stool over to the buffet table and letting them choose.
I personally recommend watering with teas...not necessarily the entire time, but at least every third watering...adding fish emulsion etc during veg, and high P bat guano during flower...molasses molasses molasses...