here's one website that can help and gives some tips and guidelines

http://www.mrdrip.com/moisturemaster.htm

and like the site says, burying it can make monitoring the watering difficult, so just some mulch over top is better.

but yes you can do it

Wow, great minds think alike. I have several underground hoses, because I hate rolling up the hose for my DH to mow. So --we rented a trencher for another project for a 12 volt elect line, and used it dig the 4" deep trench from the house to the first bed 90 feet away. At the house there is a 'Y' splitter. I installed a regular garden hose in the soil. There I have it connect to a above ground hose to water that 80 bed (just coil that hose on the ground). If I want to water the annuals, there is a 50 foot soaker hose just under the mulch, but remember it only wets the soil for about 8" wide, I use a quick connect to attach the soaker hose.
At the end of that bed is another underground hose of 50 feet, with a 'quick connect' to the second bed. In that bed, I used a box hose reel and use it as a chair when I'm tired over there. The 150 feet of hose on that reel, waters that whole bed and then must go over the grass to reach another bed in the yard installed recently (very seldom water it though). I don't even blow out the hose before winter, and they are dong fine after 4 years, I just disconnect it from the faucet and let gravity drain it. I have a similar set up up the other side of the house, but only have one bed to reach over there. We are on a well, and pushing that much water uphill gives me low pressure, but the system works great and the old hoses were free--salvaged and needed to just fix the ends. Yes I have cut the hoses in a different project and used the hose repair kits, even used those kits on soaker hoses too. I wish I had done this at other houses.
By the way, the end of the underground hoses are 2 feet from the bed edge with a rock/board over that area (or ran it through a salvaged piece of downspout-to protect it from the shovel and lawn mower.

Why don't you just run PVC add a female fitting put a hose bib and the run drip irrigation with micro sprinklers and emitters. Sorry if i'm throwing out strange gramer but i'm a irrigation pro.

Black poly pipe is a lot cheaper than garden hose. Our yard is 3 acres. A while ago I got tired of dragging hose back and forth, so I ran 500' of 3/4" line and put 5 hose bibs in the yard.
1/2" black poly is usually 5/8" and you can use standard repair fittings on the ends. Depending on how much you are going to put in, it may be worth going to a farm store to buy it. Here I can get a 1000 foot real for about $200.