Fertilizing
This can get really complicated, if you read books, or real simple, if you just hang out at a nursery or two. Fertilizer can be ashes, bone meal, organic plant foods, compost, and even include some synthetic fertilizers. The real secret, of course, is all that soil preparation you just did -- the double digging, the mixing of mulch, and the overall sponginess of the soil. The fertilizers give you a nice jump start to your garden, but a lot of the soil fertility comes from, well, worms. If you don't have them, get them. They will be happy to aerate your soil and crap their micro-organic lunches into it, making it rich in humic acid, as in humus. As in, holds the soil nutrition and distributes it better.
But plants gotta eat, and when they do, fertilizer can make them fatter. A fish emulsion spray is good when the planting is fresh, BEFORE the leaves come up. After that, start looking around for a decent organic fertilizer, reading the directions before you buy it. Even if it has the word "Organic" on the front, the back may have phrases like "Do not use if...” Remember the motto of the lending industry: the big print giveth, but the small print taketh away.
The organic fertilizer movement has been with us a while, so some standards have come into play with respect to packaging notes. Some organic fertilizers now have fertilizer ratios written on the label. Others, like composted manures, are “soil conditioners;” they contain only trace amounts of nutrients, and don't guarantee them.
An organic fertilizer is typically high in either phosphorus, nitrogen, or potash, but not all three. Of course, you may only need one or two. And if you need all of them, there are a few fortified fertilizers that contain all three. But the real issue about organic fertilizers is how well they work in comparison to non-organics. The effectiveness of organic fertilizer is highly dependent on your soil preparation. This stuff ain't Miracle-gro. Because organics don't contain a boatload of modern chemicals, they don’t automatically distribute perfectly unless your soil is warm and well dug.
After your first harvest, all your gardening friends will come by and talk about "green manure." This is something gardeners do. They invent magical terms to describe perfectly commonplace ideas. All it means is that you leave the cover crop to rot for a couple of weeks after the harvest, then plow it under to put nutrients back into the soil. Duh. Composting becoming popular now, first because you can go out and buy cages and kits (or build them yourself), and second, because the actual formulas for container size, layers of organics, layers of soil are pretty much set. Not a lot of guesswork. And entering the world of French Intensive Gardening, you really want systems to do the work for you whenever possible. The more systematic your approach, the less you have to scramble around trying to fit compost timing into fertilizer timing into planting timing, etc.
Water
Water when the sun will not be directly on the plants, so that the little drops on the leaves don't turn into magnifying lenses that let the sun burn holes in your leaves. Water on a specific schedule when you can, and don't go off schedule. If you leave on weekends, get a timer. Some plants need more water than others. Tomatoes and lettuce will be greedy, onions and carrots not so much.