A drip edge is a trench filled with gravel that prevents mud from splashing against your home. You install it where water drips off the roof. I also use a drip edge when the grade next to the house is the same level as the siding.
Install the drip edge one foot from the siding when controlling a grade and a little outside the drip line of a home when controlling splashing water.
If your grade is level with the siding install a drip edge level with the mulch. Leave a 1-2″ gap from the top of the edging to keep mulch from touching the siding.
Use commercial grade metal edging for drip edges. No rolled plastic from a box store. It comes in 1/8″ and 3/16″ widths that are 4″ tall and 10′ or 16′ long. This is heavy-duty stuff. If you have tight curves go with the thinner metal. There are fitting available for the edging for corners and splices to make the job look more professional.
Fill your trench with a minimum of 1″ diameter gravel. Gravel smaller than 1″ blows out of the trench when cleaning up leaves. The gravel also blocks sunlight and preventing weeds.
I use gravel with earthy tones that blends with the landscape. A river stone with rounded edges works nicely too. The choice is yours.
I don’t use weed fabric under the gravel. Weed fabric traps sediment and the gravel will soon be sprouting weeds. Not using fabric also makes the stone easier to remove should the need arise.
Apply black spray paint where you cut the edging to prevent rust. I use a Milwaukee Portaband to cut edging. A hacksaw, some elbow grease and a lot of patience works just as well.
Time spent installing a drip edge will keep you from having to replace siding, or worse, down the road.