The silky, feathery plumes of pampas grass add a nice texture to the home landscape. The plant flowers for a long time in late summer and fall, then as a bonus the plumes can be cut and dried for use indoors.
Relatively easy to grow, this is a permanent plant that provides color and interest for many years.
The large grass-like leaves also add interest to the garden. They provide textural variety in the landscape and can also be used in floral arrangements.
It is important to provide ample space for pampas grass to grow. Because once the clumps become established they can become quite large. The average garden usually has enough space for only one plant, but in the large garden a grouping of three or four plants will provide a massive display.
The most popular and common type grown is the white one, but there is also a pink variety. I think the pink is a bit washed-out in color, and therefore one I usually do not recommend.
It's not unusual for the plumes of pampas grass to attain a height of 5 to 8 feet or more at maturity, so low growing shrubs or perennials often are planted around the base for additional color. One of the most attractive planting combinations I have seen in recent years, was the use of red and yellow celosia planted at the base of the white pampas grass. Blue and red flowering plants are also attractive, with the grass foliage and white plumes of pampas grass.
Pampas grass grows well in the northwest with little or no care. (It is a pest in California, because of its rampant spreading, and cannot be grown there.) Its basic requirement is that the soil must be well drained, especially during the fall and winter rainy season. A sandy loam type soil is ideal, but not essential. In fact, it grows exceptionally well along the coast in almost pure sand.
We have ours planted in full sun, but in the northwest it will even do well in partial sun and shade. When problems develop it is usually because the clumps were planted too deeply, mulched too deeply or because the planting soil is poorly drained.
So take time to prepare the planting soil, being certain it is well drained and that you add organic humus in the form of compost, peat moss or processed manure. Dig the planting hole about 12 to 18 inches deep and about 15 to 18 inches wide, for the average size plant, grown in a gallon container. Don't be disappointed if your young plant does not have plumes for the first two or three years.
When established plants do not form plume, it is usually because they have been over watered or fed too heavily with a nitrogen-type fertilizer, which would tend to stimulate foliage growth instead of plumes.
If you have an established clump in your garden and want to get additional starts, the best time to dig and divide the clumps is in March or early April. (Although it can also be done in the late autumn.) At either of those times simply dig the clump, and take divisions from the side shoots.
The best time to cut the long flower stems for use in winter arrangements is in October. It should be done before the plumes become water-soaked. To dry them you can hang them upside-down in a cool, well-ventilated basement of garage and let them dry for a couple of weeks. Or you can simply, stand them upright in a tall (waterless) vase. Once the stems have dried do not put them in water again. As this will cause them to begin to deteriorate.
Should yellow or brown leaves spoil the appearance of your pampas grass, simply prune them as they appear. By all means wear gloves and long sleeves, or the blades of the grass-like foliage are apt to cut your hands or arms. If the foliage really looks bad, and the plants are in need of drastic pruning, it can be done in the late fall or earliest spring. If needed, you can cut it back to within just 2 to 4 inches high.
First, pampas is suited to warmer climates and is recommended for US zones 7 to 11. Pampas grass prefers a sunny spot, but will tolerate a certain amount of shade. It needs well-drained soil and will not grow in soggy ground. You don't need any fancy soil amendments to grow pampas grass -- any old garden soil will do fine. (Low-maintenance gardening: don't you love it?!)
Second, the end of your driveway is not a good spot because pampas grass grows so big it will inevitably obstruct your view of the road...and other drivers' view of you as you leave your driveway.
Third, another size-related caution: be sure the location you choose allows plenty of room for your pampas grass to spread out. It needs a space about 10x10 feet in order to reach maturity without crowding out other plants.
If those last two concerns are a problem for you, never fear: a miniature variety of pampas grass is readily available. Or consider another, smaller, species of ornamental grass, such as maiden grass or fountain grass.
Choose your planting site carefully and measure the spot just to be double-sure it is roomy enough. Let me repeat: this plant grows big and wide! Next, start digging. Now, as is always the case when planting trees, shrubs or ornamental grasses, dig a nice wide hole. Aim for a hole about three times wider than the plant's root ball.
Depth is less important. You will know the hole is deep enough when the ground is level with the crown of the plant. Break up large chunks of soil as you go. There is no need to add organic material or fertilizer.
Next, prepare the plant. Water it well, then gently slide it from the pot. Examine the roots. Ornamental grasses tend to have tough, tightly-woven roots. You will want to loosen them to speed the growth process. Pry the roots loose with a blade, cutting through when necessary. Then spread the roots outwards.
Place your plant in the ground and examine it from all angles. Make sure it is sitting straight and that it is facing forward. Check the roots a final time, then water thoroughly. Now it's time to fill in the hole with soil. When you're done, tamp down the loose dirt so the plant is nice and secure in its new home. Water again, then mulch well.
That's it! You're done. Now just wait and see how your pampas grass takes to its new location. Don't forget to water it regularly for the first few weeks. Over the next few months, water it whenever there is a long dry spell. Do this to help it along until the roots are fully established. After that, it should need no human help whatsoever.
Dangerous Sharp Leaves
And problems don't stop there. Pampas's leaves are notoriously sharp. If you must plant pampas grass, avoid planting near walkways where blades will cut the innocent passers-by. And be warned: sometimes its dense impenetrable bushes provide habitat for rats and mice.
With all that required caution, the pampas grass fix seems hardly worth the trouble. In fact, if you search for pampas grass on the Internet, one of the first sites that pops up is the National Park Service web page, encouraging you not to grow it.