How to Grow Pampas Grass in Your Garden

Welcome to our essential guide to growing and caring for Pampas Grass. With its pinnate flowering plumes, Cortaderia selloana can be the feather in your garden’s hat! Just be sure to plant a variety that has been cultivated not to self-spread, as this fancy ornamental grass is a known invasive plant species. Here, I’ll take you through everything you need to know to grow Pampas Grass at home, including planting, soil considerations, light preferences, feeding, pruning, and over-winter care.

Pampas Grass Plant Care Essentials:

Botanical Name:	Cortaderia selloana
Also Known As:	Pampas grass
Hardiness Zones:	USDA 6 to 10
Flowering Months:	Late summer to mid-winter
Growing Difficulty:	Easy to grow
Type of Plant:	Ornamental, perennial, evergreen, flowering grass
Light Requirements:	Full sun to partial shade
Temp & Humidity:	Thrives in ambient temperatures ranging from 65°F to 90°F and tolerates low to high humidity
Watering Needs:	Low to moderate water needs: water once to twice a week and more frequently in hotter, drier climates
Soil Preferences:	Well-draining, sandy, loamy soil of any pH
Feeding:	Little to no fertilizer is needed
Growth Expectations:	4 to 10 feet tall and about equally wide, depending on the variety
Toxicity:	Non-toxic to humans and pets

How to Grow Pampas Grass

Where to Plant

Although they can tolerate some shade, the best places to plant pampas grass are garden locations that receive at least 6 hours of full sun daily. Choosing an area with moist but well-draining soil is also essential.

Be sure you pick a location and a variety of pampas grass that are of a suitable size. Remember that the largest of these plants will achieve a 10-foot diameter at maturity.

Pampas grass plants are tolerant of drought, salt sprays, and wind. These plants are the perfect choice for coastal gardens, windbreaking garden edges, screens, hedgerows, and fences. More compact varieties are also suitable for beds and containers.

The Best Time of Year to Plant

If planting from seed, you can either sow them mid-winter indoors and plant the seedlings outside after the final frost has passed, or you can sow the seeds outdoors in spring.

If planting nursery plants, they are best put into the ground in springtime.

Growing From Seeds vs. Planting Nursery Plants

Although they are relatively fast growers, pampas grass plants still need 2 to 4 years to reach their mature size.

While the plants can be grown from seeds, you’ll get a headstart in growth if you purchase and plant nursery plants instead.

What to Do Before Planting

Before planting, choose a suitable location that offers your pampas grass enough room to grow, enough sunlight, and well-draining soil.

Then, gather some supplies. Depending on the size of your pampas grass plant, you’ll need sand or perlite to mix into your soil and a trowel or shovel. Additionally, you’ll want to wear some sturdy gardening gloves and long sleeves to protect yourself from the plant’s sharp stalks.

The Best Soil

When it comes to soil, pampas grass is not picky. The two most important qualities your soil should have are to hold some moisture while being well-draining.

Pampas grass grows best in sandy or loamy soils that drain well and can tolerate a range of pH levels from acidic to neutral to alkaline.

How to Plant

Once you’ve found a suitable location and are ready to plant your pampas grass, start digging a hole large enough to contain your plant’s root ball, but that is no deeper than the container your plant is in.

When in the ground, you want the base of the plant’s stalks and its clump of foliage to be level with the ground or the top of the soil in your container.

At this time, test your soil’s drainage by pouring some water into the hole in the ground. If your soil seems soggy or overly moist, mix a bit of sand or perlite into the dirt to improve drainage before planting and filling in around your plant’s roots.

Next, place your plant in the hole and fill in around its roots with your potting mix. Pat the dirt down gently and add more, if necessary.

Water thoroughly and continue watering your new plant at least once or twice a week until it is well-established.

Light Preferences

Pampas grass plants can tolerate some shade. However, they must receive at least 6 hours of full sun daily.

Temperature and Humidity Preferences

Pampas grass tolerates a wide range of temperatures and humidity levels. They thrive in ambient temperatures ranging from 65°F to 90°F and low to high humidity conditions.

They’re winter hardy down to zone 7, where brief temperatures range from 0°F to 10°F. However, these cool temperatures can harm the plants – especially if the soil is particularly wet.

In zone 6, pampas grass plants should be grown in containers and brought inside for winter.

How to Care for Pampas Grass

Watering

Pampas grass is highly adaptive to various moisture conditions but fares far better in drier conditions than in soggy, wet soil.

Water your plant once a week or twice in particularly hot, dry conditions for the first year. Depending on how much moisture you receive in your location, well-established plants might not require supplemental watering. If your climate is hot and dry, water once every two to three weeks.

Do not water pampas grass during its winter dormancy period.

Fertilizing

A light feeder, pampas grass, usually does require regular fertilization. However, to promote growth, you can apply a layer of compost or a balanced slow-release fertilizer once a year in early spring.

Pruning, Cutting Back, and Deadheading

Pampas grass flowers do not require deadheading, but the whole plant needs to be cut back every year to make room for new growth. This is best done at the end of the winter before new foliage begins to sprout.

Basic pruning shears or hedge cutters aren’t strong enough to stand up to the massive stalks of pampas grass. You’ll need long-handled loppers or a chainsaw to get the job done.

Before you begin, use a stick to poke around in the clumps of grass at the base of the plant to scare away any small creatures.

To cut back, lop everything off, leaving only about 6 to 8 inches of stubs at the base of the plant. This will encourage new growth and keep your plant healthy at the beginning of the growing season.

Propagation

While pampas grass can be propagated by seed, most varieties you acquire for your garden will be cultivated not to produce seeds to prevent the plant’s unintentional, invasive spread.

You can, however, propagate the plants through root division in the spring. To do so, dig up your plant, divide the roots and stalks into equal parts, separate them, and replant each with ample room to grow.

Overwintering

In hardiness zones 7 to 10, where pampas grass is evergreen, no special care is required for overwintering pampas grass. In zone 6, your plant’s foliage will likely die off over the winter. You can add a layer of 1 to 2 inches of mulch to protect the root system.

Container plants grown in these zones and below should be moved indoors to a warmer location.

Repotting

Due to their sheer size, pampas grass plants will likely require repotting annually. At this time, you can follow the same guidelines for planting as above and either divide the plants or move them into larger containers (about 5 to 6 inches larger).

Common Problems and How to Treat Them

Signs and Symptoms of Problems

• Browning Grass Tips – If your pampas grass’s foliage turns brown, it might need a bit of supplemental water.
• Yellow, Drooping, Slimy, or Wilted Grass Tips – Your pampas grass is overwatered. Reduce your watering frequency.

Common Pests and Diseases

One of the reasons pampas grass is so easy to grow and has become an invasive species in so many locations is that no pests or diseases seem to affect it.

This plant is not only hardy in the winters down to zone 7, but it’s also tough when it comes to staving off common garden pests and plant diseases.

Essential Tools

• Protective gloves and clothing
• Shovel
• Sand or perlite
• Long-handled loppers or a chainsaw
• Balanced fertilizer

A Feathery Fortune for Your Garden

While pampas grass has its negative traits (invasive tendencies), it can be a real showstopper in the garden with its attractive grass and silvery, feather-like flowers. Just be sure to grow it responsibly!