SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

As you've pointed out, the "problem" is the mixing of plants that need different watering schedules.

That said, it's still do-able, and not look like a hack job, but once you have things set up it will be difficult to change things. Here's what I mean... what you'll need to do to account for the watering schedules is to determine how much water the plants are going to need in a week, and compare that to your weekly watering schedule. Then you place the appropriate size and number of drip emmitters to get the desired amount of water to the plant during the time the lawn is watered. Of course if and when you ever change the schedule, the size/count of emmitters might need to change as well.

Otherwise, the key things you need to go to drip are a pressure regulator and a filter. One plan would be to tap into your existing line, run the tap to a valve box somewhere, then place the required regulator and filter in the valve box. Then run some more pipe from the valve box to a point above ground. The way I like to do that is run 1/2" copper from the valve box to the surface, and possibly up the sides of any pots... basically use copper anywere a week wacker is likely to ever be. Then terminate the copper with a copper female, and find a drip hose connector with a PIPE Threaded male like these (http://www.lowes.com/pd_88290-1029-MLA-P2P_4294821977_44?productId=1103275) you can find at Lowe's. The thing to keep in mind is that the Drip Kits you see are usually designed to work with a garden house, and the threads on a garden hose and spickot are different that threads for pipe. As such, you would need to get filters and pressure regulators from an irrigation supply house rather than any sort of drip kit you'll find at a big box retail store. You need filters and regulators designed to go on pipe and pipe threaded connections, not garden hose threaded connections.

Drip irrigation requires fine-mesh filtration, even on city water.

If you want to go the way of true "drip irrigation", here's an example of a pressure regulator...
http://www.sprinklerwarehouse.com/18-030-Preset-Pressure-Regulator-p/18-030.htm
... but you would need a seperate filter.

They do have this kit...
http://www.sprinklerwarehouse.com/P40-075-Drip-Zone-Assembly-p/p40-075.htm
... that has the regulator and filter together, but you also have the unneeded valve (but that can be tossed). These can be purchased seperately, but I don't see where this site's sponsor sells THIS filter seperately. The filters they do have look like they are more designed for hose bibb applications that in an underground valve box.

As for the adapter you pointed out, it does have a filter in it, but it's listed as 120 mesh. Drip irrigation where you use emmitters usually require 150 mesh (higher the number the finer the mesh).

Otherwise, to combine drip irrigation with controlability, use something like these...
http://www.sprinklerwarehouse.com/06-012-Adjustable-Drip-Emitters-Stake-p/06-012.htm
You twist the cap to change the flow rate... and they are better when you don't have the fine filtration like WetBoots pointed out. They also make some that can go on drip tubing like the "standard" drip irrigation emmitters. The difference is while finer drip emmitters put out .5 to 2 gph, these are more like 2 to 10 gph, and throw the water a few feet.

But basically, once you tap into an existing line, add a regulator and fine mesh filter, you then have all sorts of drip irrigation options, from those available on this sponsor's site to local big box supply houses.