Adding stairs to your garden will make it easier for visitors to get around. You will lose some lawn or planting space when you put in stairs, but you will gain access to more areas on your property. Stairs help to define sections of your garden. For example, taking stairs to move from a rose garden to a tropical space reinforces the notion that you are entering a different space more effectively than walking up a slope.
Measure the area where you will place the stairs. Stand a straight piece of wood where you want to place the top of the stairs and one where the stairs will end. Mark on the wood pieces the height of top step and the bottom step. Position a third piece of wood so that it angles down from the top piece to the bottom piece. Measure the horizontal span and find the depth of the tread by dividing by the total number of steps you want.
Design your steps so the risers are no more than 6 inches high and the treads are at least 11 inches deep, as Black and Decker recommends for dimensions for all garden stairs. Extend your staircase design to accommodate the proper step size.
Compact the ground by tamping down the area manually or with rented machinery.
Pour a 6-inch thick concrete pad. Place ½-inch steel reinforcing bars in a grid pattern in the wet concrete. Space the bars 1 foot apart.
Wait at least 24 hours after you pour the concrete to place pre-purchased concrete blocks on the pad. Use blocks that are the same width, depth and tread height as your planned completed steps.
Check the blocks for level from side to side. Shape the treads until they slope downward and outward to prevent water from pooling on the steps. Create a tilt of 1/8th inch per 1 foot of fall to each tread, as recommended by builder Tim Carter of Ask the Builder, for good drainage.
Spread a mortar mixture of Portland cement and fine sand onto one side of a brick and on the concrete block. The exact proportions you use depend on your geographic location because of differences in freeze-thaw cycles. Work in small sections. Press each brick onto the block. Tap gently to secure the brick into mortar. Repeat this process until you have covered the tread of the step
Position a brick on its long, narrow face. Add ½-inch of mortar to the back, top and bottom of the brick to create the risers. Place the risers flush against the concrete at the back edge of the tread. Add enough bricks to complete the row of risers.
Add bricks to the top tread. Measure any overlap of the tread over the risers to ensure that they are even and not greater than 1 or 2 inches.