While the most common planting process for ornamental grass is to place small grass plants directly into the ground to establish plantings, many types of ornamental grass also propagate easily by seed. When you plant ornamental grasses by seed propagation, you can create dense growth or lighter growth, according to the amount of seeds you sow. Choose your ornamental grass variety and plant the grass seeds to grow a lively stand of tall grass.
Select a planting area that receives at least six hours of daily sunlight. Prepare the area for planting in the spring after the final spring frost. Cultivate the soil with the garden spade down to a depth of 3 to 4 inches. Add 1 to 2 inches of compost over the top of the soil and work this in thoroughly with the garden spade.
Spread ornamental grass seeds evenly over the planting area. Broadcasting the seeds in small groupings is an effective way to create separate stands of grass. Another option is to broadcast the seeds evenly over the entire planting area to create one large stand of ornamental grass. Sow the seeds as thickly or as thinly as you desire, according to the finished effect you want.
Cover the seeds with approximately ¼-inch of soil. Spray the soil evenly with a light sprinkling of water to saturate the planting area.
Keep the soil evenly moist while the ornamental grass seeds germinate. Water the soil once or twice each day to ensure the soil stays moist.
Fertilize the ornamental grass for the first time when the grass reaches 6 to 8 inches in height. Mix the fertilizer with water according to package recommendations, and pour the fertilizer carefully over the soil. Fertilize the grass once per month during the growing season.
Allow the grass to stand throughout the autumn and winter. This achieves two purposes. Leaving the grass standing will provide a winter focal point in your landscape, and the standing grass will also drop seeds onto the soil for self-sowing (if the ornamental grass is an annual variety).
Cut the ornamental grass down with pruning shears to just above the soil level the following spring in preparation for new grass growth in the planting area.