Pressure wash the front of the foundation to remove dirt and dust. Once the foundation is clean, let it dry for 48 hours.
Cut a piece of diamond lath mesh to the length and width of the foundation front with metal cutters. Trim this one piece down into multiple pieces so each one is simple for you to maneuver. Attach the pieces of lath to the foundation with masonry fasteners so the front of the foundation is completely covered and none of the pieces overlap.
Place two plastic buckets on a flat surface near the foundation's front. Pour 1 part Portland cement into one bucket and 2 parts Portland cement in the other. Add 3 parts medium sand and 1/2 part hydrated lime to the bucket with 1 part Portland cement.
Add a little bit of water at a time to the bucket with the three different ingredients, and stir the mixture with a shovel until the consistency is similar to cake batter and uniform throughout. Do the same to the bucket that contains only Portland cement, but make sure this mixture is much thinner, like paint.
Work on a few feet of the foundation at a time. Dip a large paintbrush into the mixture of Portland cement and water. Apply it quickly and evenly to the first section of the foundation.
Scoop up some stucco, which is the multiple-ingredient mixture, on a masonry trowel. Apply a 1/4-inch-thick layer of stucco to the damp section of foundation. Spread the stucco evenly and smooth the surface with the flat of the trowel.
Continue applying the cement mixture and the stucco to the remainder of the length of the foundation front. Allow the stucco to dry for about five days; if the forecast calls for rain, create a lean-to covering over the foundation from plastic tarps. For the first three days, spray the foundation sparingly with water to prolong the cure and ensure the stucco dries very strong.