The 'right next to each other' bit might be a problem. It is generally considered a good idea to group plants that take the same conditions. You usually can't water one plant with a funnel and the one beside it with an eyedropper.

Another consideration is your water -- does it have a lot of minerals? Minerals tend to clog many drip systems after a while.

Do your homework before you invest your money.

I have drip tape in my garden with 1/2" header line made out of pvc and valves installed on each of the outlets. I have corn, tomatoes, watermelons, squash, canteloupes, onions, beans, peppers and cucumbers all in the same garden on the same system. When it gets dry i just water them all the same (takes about 2 hours to water good) but you might be able to adjust the valve to adjust water flow to one row. It supposed to take at least 4psi to open the emitter and 12psi is the max. This system has a 12psi regulator and a filter on it too. Dont know where you live but i bought all this at my local TN Farmers Coop.

You can organize your plants into "zones" that are watered on different schedules. Dripworks is a very good supplier who will help you design your system.

That said, simplicity is good. You're probably better off watering everything on the same schedule. You won't kill your lettuce by giving it as much water as your tomatoes.

I've used 1/4" dripline to keep a garden watered while away for up to several weeks at a time. It's a great labor-saver, and has the bonus of keeping water away from plant leaves, reducing the risk of disease.

Agree that a zone organization is the best way to go - difficult to do after planting so best done before.

Different plants have very different watering needs as you already pointed out so with drip irrigation, once it is in place, it is the system that determines the planting zones, not the other way around.

To set up a system AFTER planting is 'possible' using spider arms off the main system but requires more parts - extra "Y" and interim shut offs - say where your lettuce ends and the tomatoes begin for example - but that also has the advantage of helping you avoid log runs of tubing that will deliver water unevenly to the emitters.

Also keep in mind when building it for this year that things like lettuce will soon be finished if not already so they can be replaced with plants that will let that row run all at the same time.

Hope this helps.

Dave

PS: another vote for Dripworks as a good source

I got my stuff from Dripworks but I still had to buy adapters locally. Lots of valves, and zoning the vegetables in groups with similar water intake, as others have said, is the way to go. FYI, I tend to group large brassicas together, (cardoon and celery), (tomato, pepper and eggplants), (and squash and beans). Under the tomatoes you can plant chicory, but lettuce may not be ideal. It is quite an exercise to get them to fit together. I suggest you keep a log.

Zoning will be difficult as i plant in small blocks down the rows and each block may host four or five different crops in a year's time. And i like to try to rotate families to keep the soil bugs from getting out of hand.

I think i like Dave's idea, if i'm understanding it correctly. Black 1/2" tubing down the rows as supply lines with different emitter types plugged in. Tomatoes might like big bubblers cranked all the way up, maybe with a manual in-line shut-off valve just after the tee so they could be turned on just once a week. Lettuce might want some of that 1/4" line with the built-in emitters. Might need to stock up on goof plugs, tho ; ))

I'm curious about the micro spray emitters. Anyone have experience with them?

I love drip systems, they keep the plants watered with out "wasting" water like so with spraying the water. Depending on the size of your garden though will determine what might work better. I did a main head with lines to each plant ,35 plants, and a lot of work. like this though you also can buy different water emitters, some to flow like 1 gallon per hour or some that will do like 3 gallons a hour. They choices are endless and you can even set the watering cycle on a timer and not have to worry about watering at all once you have it set up right. Its a lot of work to set up and can get pricey.

This season I have been using the regular black water hose that water seeps out of with good results, its easier for me and works just as good IMO. The hose is like 10 dollars for a 50' run and again you can get creative and add more or less line. The route the hose through the garden around your plants. Try and move them further away from the plants you dont want to get a lot of water, but organization of the plants is best. I have my garden about 200' from the house so I routed regular water hoses along the fence line to the garden and then hooked it the soaker hoses. Once a week try and spray the plants with water. I like to do this to knock any pest of the plants. Also put you plants that like a lot of water on the front of the line and plants that like less water in the end of the line, you will lose some pressure in water as you get to the end of the line.
Grab a glass of tea and sit in your chair and relax looking at your garden while its being watered with soaker hoses 20 dollar timer.

maui, there are a lot of different types of spray emitters. There are also misting emitters that you can use to keep a seedbed moist. I've tried out many of them and, in my experience, they all work very well. It just depends on your application. You can buy an inexpensive "sampler" to try out a dozen or so types before you decide.

I found that the water from the ones that spray a fine mist straight upwards is often moved by the wind before it lands. That might not matter much for a farm field or very large bed, but it made those unsuitable for my narrow rows.

Last year, I made the mistake of misting seedbeds near tomato plantings. That splashed water up on the tomato plants and probably contributed to fungal diseases like Septoria.

Expect some experimentation at first and you'll find a setup that works great for your garden and style.