Sheet mulching is my favourite way to suppress grass and weeds and start a new bed. My approach is: first, a layer of cardboard, overlapping such that there is nowhere for grass to penetrate; next a layer of well-rotted manure; then a layer of straw--NOT HAY, (you'd be amazed how many people mistakenly use hay, as opposed to straw!); finally a layer of good topsoil, or my favourite, SeaSoil. You can then plant directly into this top layer. Not only do you avoid all the work of tilling, but you promote a much healthier soil ecology, and subsequently better plants. Be careful of your topsoil sources--I have seen a lot of properties unwittingly import horsetail, morning glory, and other nasty beasts by purchasing cheap material. That will leave you longing for bermuda grass! There is a lot of info on the web about sheet mulching, or 'lasagne gardening', as it sometimes called. A soil test is always a good idea. It will inform you of any deficient or toxic mineral levels, and if you need to adjust your soil pH. Personally, I think you will never make a better investment in your garden. I would mention that using pressure treated lumber for a vegetable garden is not advisable. I would replace it with rough cedar, which is relatively cheap, and will last years.

15 years??? Some seeds???? The reason the lawn is thin near the pavement is the pavement holds the heat from the sun and dries the soil out all day and all night. You might consider something different or plan to water a little extra near the concrete. What time of day are you watering? How long do you water? You should be watering about an inch at a time (measure with cat food or tuna cans). And you should only be watering once a month this time of year. And this would be a good place to mention that it would be much more helpful to tell us the town you live in. Zone 10 CA is not helpful at all. I'm guessing San Diego, but it could easily be Calexico where conditions are much different. The close up pic is of bermuda grass. It does not look like the rest of the yard is bermuda. Bermuda likes different care from most other grasses. It really likes to be mowed at your mower's lowest setting. Fescue, your likely other grass type, likes to be mowed at the mower's highest setting. You can decide now which one you like more and just set your mower for that height. It will take care of itself for the most part. Fescue, however, will need to be reseeded in the fall if you want to thicken it up. It does not spread like bermuda grass. If you are near the coast (really need to know) then Kentucky bluegrass makes an incredible lawn. You would have to start over but that is not that difficult. You would have all summer to think about that. I'll attach a pic of a KBG lawn near Long Beach. Nothing will grow on the south side of the hedge you have out front. If you are going to leave that in, you should plant flowers or something on the north side of that. The reason your back yard is bumpy is that someone in the past has rototilled the soil. They might have had a garden once. You can level that by adding sand to the holes. If you want to dig up the high spots, that becomes a lot more work. Thank you thank you thank you for posting pictures. Now tell us where you live! Here is some general lawn care best practices. These are not mine. In fact when I first started doing this, I disagreed with all of it, but by reading here over the years, these really (REALLY) do work. They are in order of importance. 1. Water deeply and infrequently. As I described above, water all at one time but not very often. Monthly in the cool months working your way up to every 7 days if you really get HOT. Don't fall for the plan of watering a little bit every day - even if your neighbors all do that. It is a recipe for disease and weeds. 2. Mulch mow at the mower's highest setting unless you have bermuda, bentgrass (you don't) or centipede (you don't). 3. If you are going to use chemical fertilizers, do the first app any time after you mow real grass for the second time in the spring. Fertilizing before that is a waste of fertilizer because your roots are not ready. A good starting schedule is Memorial Day, Labor Day, and Thanksgiving. If you are going to use organic fertilizer (look for the Organic Lawn Care FAQ on the FAQs of the GardenWeb Organic Gardening Forum), then you can fertilize any day of the year, or every day of the year, almost as much as you can afford. It is very hard to overdo organic fertilizer. If you decide to go with bermuda, it can use chemical fertilizer every month. Bermuda is a nitrogen hog. Other grasses cannot tolerate chemical ferts in the summer. KBG lawn in Huntington Beach. All he does is water infrequently, mow high, and occasionally fertilize with used coffee grounds.

Lou, I agree about the sharp sand but I'm not going to be a stickler about it...yet. I'm just having a hard time arguing with the OP's results, and he used river sand. I would offer it as an alternative and suggest the pros and cons, as you did, but with these results I am backing off on my former insistence on sharp sand. For example what if sharp sand packed down on top of the grass and slowed the regrowth of the bermuda? Round sand won't do that and could actually be the reason why this method works. Like I said in my first reply to this, I've seen bermuda killed by applying this much sand. Oh, and the OP did core aerate as part of his project. I think I agree with the importance of that. I may be changing several of my opinions based on this topic. For example 1. Rounded (river) sand may not be as bad as we have been thinking. 2. Core aeration may not always be a complete and utter waste of time, energy, and money. 3. Smothering bermuda with sand may not kill it if you prepare it right and provide proper follow on care. I don't know if the OP accidentally stumbled on a method that works or he read it somewhere or what. But hey, it really did work. In all the years of reading this forum, this is the first time I've seen real solution to this frequently asked question. I think the ideas need to be captured and saved as a FAQ. I'm willing to write it up and give the OP full credit. Unfortunately iVillage doesn't want pictures in their FAQs. Too bad because I would not have believed it if I had not seen the pix. So I have something else in mind besides a FAQ here.

BTW, do you know if centipede will generally choke out weeds and BAHAIA grass if it's maintained? Any secrets? Proper mowing and watering practices are going to be your best defense against weeds and Bahia grass. For example: Bahia prefers to be cut high 4+" where centipede should be mowed low at 1-2". Cutting low will help your lawn become dense and spread outward, and should choke out some of the Bahia over time. MOWING: Mow at 1 to 1-1/2 inches. Mulch mow with sharp blades, and mow often enough so only 1/3 of the plant height is removed. High and infrequent mowing tends to encourage thatch development, which can lead to chlorosis, drought stress and winter injury. However, during periods of drought the mowing height should be raised about 1/2 inch. WATERING: No more than once a week, but the best way is to Let Your Lawn Tell You When it Needs Water. As the soil begins to dry out, the lawn will show a lack of available moisture by wilted leaf blades. This condition is evidenced by a lengthwise folding or rolling of the blades, caused by a loss of turgor or water pressure within the plant. Also Footprints remain visible on a drought-stressed lawn long after having been made. Unless rain is forecast in the next 24 hours, lawns should be irrigated when 30 to 50 percent of the lawn shows signs of wilt/stress. Irrigate in the early morning hours between 2-6am Your objective when irrigating is to get the maximum amount of water to the root zone without over-irrigating. In clay soils,(which Im assuming you have) is somewhere between 1/2 to 3/4 inch of water. This will target the majority of the root system and encourage more rooting at lower depths. So, how do you know how to apply this amount of water? An easy method of measuring the amount of water applied by your irrigation system is to set out several straight-sided, same-size cans (tuna cans work best) at random in each irrigation zone. Monitor how much water is applied if you run your irrigation system for fifteen minutes by measuring the amounts in the cans. If, for example, you have 1/4 inch after that time, your system should run for thirty minutes to apply 1/2 inch of water.