When to Trim Pampas Grass

Pampas grass is a large perennial plant that can reach heights of up to 10 feet and spread as wide as 6 feet. It is important to trim the plant properly to keep it looking its best in your landscape. Silvery or pinkish-white plumes rise from the stalks in the center of the plant during the late summer months.

Trim the pampas grass during the late winter months. Pruning it before the next growing season ensures that the plant maintains a pleasing shape and height for the next season. The grass holds no particular interest during the winter, therefore pruning it at this time is not detrimental to the appearance.

Green, grass-like blades surround the bottom of this plant. The leaf blades are sharply serrated, so wear a long-sleeved shirt and heavy-duty works gloves to protect your skin from nicks, scrapes and irritations. Prune yellow or brown leaves as they appear to keep the pampas grass looking attractive and healthy.

Use power pruners, hedge or lopping shears to prune the grass and stalks. Use a complete fertilizer, such as 8-8-8 or 10-10-10 after pruning. The application helps stimulate new growth. Pampas grass grows quickly and quite large, therefore it is not suitable for all lawns. Cut it back to a height of 2 to 4 inches if it needs a drastic pruning.

Once the plumes fully emerge, you can cut them off to use in flower arrangements. It is important to do this before they mature and start to shed. Spray the plumes with a light coat of hair spray to use in fresh arrangements and to prevent shedding. Young plants often don't develop the attractive plumes for two or three years. If you are growing pampas grass mainly for its plumes, avoid over-watering or fertilizing it too heavily. This stimulates growth, not plumes. To dry the plumes, cut them off and tie a rubber band around the stalks. Hang them upside down in a cool, well-ventilated area, such as a basement or garage. They dry within a couple of weeks.