You would probably get more info if you go to the garden web forum page and then go to the irrigation forum. There is a soaker hose post there now. Since this is the grden JUNK forum questions like this should be put on the conversations side. Main garden junk page--Top of page has 'discussions' and to the side says 'switch to conversations'.

I have the same concerns as the original poster. I know I've heard that it isn't safe to grow edible crops inside old rubber tires (used as raised beds), so why should it be safe to water edible crops with hoses made from old rubber tires? The flat soaker hose that Veeta linked to above looks like a somewhat better bet, but a) the customer reviews say it works well only when laid in a more-or-less straight line (and I like to loop my soaker hoses around through my garden), and b) it's no longer available anyway. Too bad! It's been only a few years since drinking-water-safe hoses of any kind have been readily available, so maybe if we keep asking for DWS soaker hoses, someone will start providing them -- though spedigrees raises an interesting question, "...drinking water hoses I believe are rated as safe because they contain a liner, and poking holes through it would probably defeat the efficacy of the liner." If that's true, then manufacturing them might not be a simple matter, either.

sb, At least 1" with 1 inch manifold. Not much more expensive. 1 1/2 if you want. Larger the better. How many 25 ft hoses do you want to run at the same time from your manifold? Are you planning to run a one 9-zone controller or 2 4-zone controller? What is your water supply flow rate and pressure? Aloha

Drippers are too local, and you end up with a very wet tear drop blob of soil with the point of the tear under the dripper. More likely you want what are called spray stakes. Usually you will want two per tree, as many trees don't like to have water sprayed on their trunk on a regular basis. You can use 1 that has a notch in the spray pattern. This will work for young trees. The sprayer is mounted on a stake, ranging from 6 inches to 3 feet high. A chunk of quarter inch spaghetti tube runs from the stake to a distribution line. Typically a spray stake waters at 5 to 15 gallons per hour. 1/2" distribution line handles 300 gallons per hour, so unless your garden is very large, you can probably do it on a single line. You also need to put a decent water filter, typically 140 mesh, to keep the tiny orifices from clogging. Most systems are component. You can choose various bits. There is often a problem with algae in small systems, especially if they are used infrequently. About once a month, when you run the system do a walk through and verify that everthing is working. I like to do this on a hot afternoon, as I always get soaked taking apart sprayers and sprinklers to clean them while the system is pressurized.