Pampas grass is quite unlike your average grass species as it creates giant clumps of foliage and massive colorful seed plumes that can reach a height of 10 feet or more. The plant is prized for its relatively low-maintenance nature, but you'll still have to carry out basic tending--bi-weekly waterings and an annual pruning, for example--to maximize the ornamental grass' beauty.
Water the pampas grass once every 1 to 2 weeks, providing approximately an inch of water per watering session. Too much water will cause this drought-tolerant plant to produce less of its ornamental seed heads, so space watering out as much as possible. Use the plant's appearance as an indicator--slight yellowing or wilting means water is needed.
Add an inch of mulch around the pampas grass clump. Keep a slight open space around the grass clump's base because constant contact with the mulch can cause the pampas grass to rot. This conserves soil moisture and lowers the plant's need for watering even more.
Cut off the pampas grass' seed plumes in the fall months of October or November. Hang the plumes in a cool and dry location for 3 to 5 weeks to preserve the plumes for dried flower arrangements.
Prune back the pampas grass in the spring as soon as the plant begins to emerge from winter dormancy. Use pruning shears and cut off all dead foliage and brown stalks as close to the grass clump's base as possible.
Rake the pampas grass with a hard-tined rake. Brush the pampas grass vigorously to tear out any loose, broken or dead foliage that's hanging on the edge of the clump. Collect all the raked and pruned foliage and discard it or throw it in your compost bin.
Fertilize the pampas grass once a year in the spring. Use a standard slow-release fertilizer with a nitrogen, phosphorous and potassium ratio of 4-1-2 or 3-1-2. Apply according to the fertilizer package's label, as potency varies by product.