Handpicking and raking is the only way to get rid of the trash. Leveling the soil will really help to conserve water, as it will prevent it from running downhill. Invest in a $6 "line level" that you will attach to a nylon string. Rake or move all the rocks to the low end of the plot. Use your line level (on a stretched out string) to find out how much you will have to build up the low end of your plot. Anchor one end of the string/level with a large rock on the high end of the plot, and stretch it across the plot, raising the string on the low end of the plot and see how much higher the low end needs to be to make the bubble in the level centered, and pile your row of rocks that high. Then either move some soil from the high end to the low end to make it level, or bring in additional topsoil/compost to bring the low end up to the same height as the top of the rocks. If you're bringing in compost, it would be best if you leveled the soil, then added the compost in an even layer. Plastic mulch isn't going to do anything to improve the soil, so I would advise plant mulch, as it will help keep moisture in the soil as well as keeping the weeds down and the soil cooler. A compost pile in one corner would be a helpful thing to have, whatever size it turns out to be. The smaller the debris is that is added, the faster it will break down. I know many people advocate putting sticks on the bottom, but I don't think it does much good, but it sure drives you crazy when you try to turn the compost and keep hitting that junk with your fork. BTW, invest in a spading fork, you'll never regret it, good for digging and for turning compost. Fencing: The plastic stuff is pretty fragile, as I have discovered -- raccoons climbing it will tear it down. The cheapest, most useful fencing would be 100 feet of 36" tall welded wire fencing (2x4" holes) and 7 heavy-duty pound-in metal posts (try to borrow a fencepost-pounder, a metal tube with handles). Put a post in each corner, and one in the middle of each long side. Put the last post 3 or 4 feet from a corner, where your 'gate' will be. Be sure to make the gate wide enough for the widest thing you will be bringing in there (like a wheelbarrow or rototiller). Start wrapping the fencing around the plot, starting at one of your gate posts (this is easier with at least two people) and come around back to the other gatepost -- don't cover the gate opening! Fasten the fencing to the second gatepost and cut the wire with wirecutters. (Clips should come with the fenceposts-- ASK!) Now cut a piece for the gate, as wide as the opening plus one more row of holes, so it's just a little wider than the opening. Use 3 or 4 black cable ties (also called 'zip ties' -- black is more resistant to sunlight) as hinges to fasten the gate to one of the posts, but not too tight, as they have to move a bit. The best thing for the fastener is a metal rod about 3/8" diameter and about 4 feet long. A hardware store or metal fabrication shop should have something that doesn't cost much -- have them make a right-angle bend in it about 41" from one end (if they can't/won't, find someone with a chainlink fence, remove one of the caps from the support pipes, stick the end of the rod in to where you marked the bend, and bend it). And you'll need one regular red brick. Weave the long end of the metal rod down through the gate holes so it's close to the post (if you need to keep it in place, use a few more of those black cable ties). It should stick out at the bottom about 4" or so and stick into the ground to keep the gate closed. Dig a hole for the brick so it's on the gate-side of the rod (to hold it in place), and so the top of the brick is level with the ground. Cut a piece of any kind of rope for the gate fastener about a foot long. Make a loop that just fits over the rod (between the bend and the top of the gate mesh wire, and reaches easily over to the fence post. To close the gate, jam the bottom of the rod into the ground by the gatepost and on the far side of the brick, loop the rope over the top of the fencepost and swing the L toward the hinge side so an animal can't push in. To open the gate, swing the bent rod toward the fence and lift the rope off the fencepost, and lift the rod out of the ground. With the leftover fencing, you'll make a barrier to keep rabbits and groundhogs from digging under your fence. Use your wirecutters to split it right down the middle lengthwise (right in the middle of the mesh squares so you have prongs sticking out on each edge) so you have two long pieces. Lay each length on the ground just outside your finished fence (long sides first) with the freshly-cut prongs pointing at the fence. Make sure the long lengths of cut mesh extend past the standing fence corners by at least 18" on all four ends for overlap, then cut off the excess. Use the excess to do the same on the shorter ends of your fence, again with the prongs facing toward the plot, again with an extra 18" sticking off the ends. All the corners should be overlapping. It would be best to lay them down so the curve of the mesh is downward, or the ends may stick up and trip people. Now push the flat pieces right up against your standing fence, sliding the prongs under the fence, and bend the prongs up and around the bottom wire of the standing fence. You can do all of them if you want, or just every 6" or so, and cut off the extra prongs. Do this all the way around, including the section right in front of the gate. Fix the soil before you install the fence, it will be easier. Your fence can also be a trellis.

There isn't really an organic post-emergent herbicide. Corn gluten meal has a pre-emergent control on some weeds. The really organic post-ermergent means of weed control are hand-pulling or treatments with things like vinegar. The biggest adjustment going to organic from synthetic fertilizer is getting used to the lag time. My father-in-law hoses his yard with miracle-gro and the grass is growing like the dickens within a couple days. When you apply grains as fertilizer, you need to expect to wait about 3 weeks to start seeing a difference. I started with the organic fertilizing last year, but still am working against many years of neglect from the previous homeowner. I think it just takes patience. This is my first spring and now all the dormant wild onion bulbs that I hadn't seen last fall woke up and have tufts all over the yard. I'll probably need to do some targeted nuking with herbicide. I'll stay with the organic fertilizing and hopefully next year there will be few enough onions that I can hand pull them. By then my grass will be stronger too. A strong dense stand of grass is the best defense against weeds! Good luck!

It sounds silly but the answer to 'how often' is 'as often as possible'. As kimmsr says, regular patrolling and removing the odd seedling as soon as you spot it will save a lot of time and effort in the long run. Weeding is an integral part of gardening and some of us quite enjoy it. It is very relaxing just sitting or kneeling in the garden weeding and musing. It is also a way of getting to know your plants intimately and recognise them in all the growth stages. Anyone who weeds regularly soon stops pulling up desirables by mistake. Weeding is also an opportunity to spot pests before they become a problem.

Those humongous beetle grubs really do help break down organic matter into compost! When I opened one plastic bag of leaves, which I had been saving since spring, I was surprised to find nothing but pure black evenly moist compost. What???? When I emptied the bag I found about about 18 huge rhinoceros beetle grubs in it . Evidently a mama beetle had laid her eggs in the leaves, rain water had leaked in to provide moisture and those guys went to work making wonderful rich compost. The 18 grubs went into my compost pile to finish their life cycle and the compost into the hole where I am transplanting some yellow cestrum ... :-) Isn't nature amazing! Oh, and I had enough leaves to thickly cover the barely emerging weeds, which will be enough to smother them.