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How to Thin Out Ornamental Grass

Ornamental grass serves as a hardy perennial in the landscape. These plants require very little maintenance except when the grass exhibits one or two annoying habits. Extremely tall grass can flop over and disturb the graceful clumping nature of these ornamental plants. These grasses also have the tendency to increase substantially in size to the point of overwhelming the garden plot. There are a couple of ways to lighten the foliage load to promote a healthier and more attractive plant.

Thinning to Remove Foliage

Put on protective clothing to limit scratches and cuts from sharp grass blades. Wear a pair of thick gardening gloves to protect your hands.

Run your fingers through the leaves of the ornamental grass just like you would run your hands through hair. Each pass will untangle grass blades and remove blades that are dying near the base. Set the dead blades aside and continue running your hands through the grass to remove more foliage.

Select the widest grass blades that exhibit some tearing or damage to the tips. Clip these blades close to the ground to thin out the plant. Select blades in various locations throughout the plant to evenly disperse the pruning. This method opens up the plant to allow light into the center of the ornamental grass.

Thinning by Transplant

Schedule this type of thinning in the spring just after new growth appears. Prune the grass to a length of 6 to 8 inches from the ground to make removal easier.

Dig 3 to 6 inches deep into the soil around the outside of the clump of grass. Thinning for transplant requires the removal of the entire grass plant. Loosen the soil with the shovel first and then slip the shovel beneath the center of the plant to free stubborn roots.

Gently wiggle the soil to pull the ornamental grass free from the ground. Avoid tugging the pruned stalks to limit damage to the plant. Keep working the shovel around the plant, gradually sliding the shovel under the grass clump to remove the entire plant from the ground.

Lift the clump onto a flat area of the garden bed. Place a shovel into the center of the root ball and step down sharply to cut the clump in half. If you prefer, chop these two clumps into smaller sections for transplant to a new location.

Replant one section of the ornamental grass in the original location. Fill in completely around the roots and press firmly down on the soil to improve stability. Transplant the separated clumps in other areas. Water the original plant and all divisions regularly to keep soil evenly moist as the plants adjust to their new location.

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