With their fluffy, cream or silver-pink flowers standing tall, pampas grass makes a striking addition to any garden
Few plants create such a striking presence as the mighty pampas grass.
Reaching anywhere between five and fifteen feet depending on the climate, this towering ornamental grass adds an arresting, dramatic beauty to any landscape and is often used to provide an organic alternative to fences and walls as a garden border.
Yet that’s not the only reason that so many people have been successfully growing pampas grass on their properties.
Along with its unmistakable, distinctive appearance, the plant (also known by its Latin name Cortaderia Selloana) is incredibly easy to grow.
Below, we’ll reveal just how easy it is with sixteen quick and simple tips to help you add pampas’ fluffy, feathery plumes to your outdoor space, but before we do, a quick word of warning:
Unlike some plants which require very little maintenance, Cortaderia requires a lot of work to take care of. It is an invasive plant that spreads rampantly and can be so difficult to contain that it is actually outlawed in places like Hawaii, California, and Australia.
Convinced that you’ve got the time and energy to invest in growing this remarkable plant?
Then let’s dive into everything you need to know to safely and successfully make pampas a part of your garden.
1: Be Prepared for a Long-Term Commitment
Pampas grass requires regular yearly maintenance and is very hard to get rid of once planted, so the decision to grow it isn’t one that should be taken lightly.
While it’s certainly true that pampas grass can make a beautiful addition to your garden, the decision to plant it isn’t one you should take lightly.
If you’re determined to sew those seeds, be prepared to have pampas as a prominent feature of your garden for many years ahead.
If you grow it and then decide six months later that you don’t like the look of it, you’ll find it incredibly difficult -if not impossible- to get rid of and may end up with a life-long battle with this notoriously persistent plant ahead of you.
In making your decision, there’s another important question you need to ask yourself:
Are you prepared for all the work you’ll need to do year in, year out in keeping your pampas under control?
If you neglect it, it will soon run rampant across your garden, overwhelming your other plants and destroying the beautiful aesthetic you’ve worked so hard to create.
In other words, your relationship with your pampas grass will not be fleeting. It’s a long-term commitment that certainly shouldn’t be taken lightly.
2: Understand the Difference Between Cortaderia Selloana and Cortaderia Jubata
Tall and sharp, Cortaderia Jubata combines all of the drawbacks of growing pampas with none of the benefits and should be avoided at all costs.
There’s another reason to be very careful when deciding to grow pampas grass:
Picking the wrong type can spell disaster.
Like all plants, pampas can be found in different cultivars, and one, in particular, is well known as the worst of the worst.
Cortaderia jubata is a sharp, dun-colored weed which, rather than adding that sense of dramatic beauty, leaves your garden looking overrun, neglected and ugly.
Each plume produces up to 100,000 seeds that can spread over distances as far as 20-miles, making jubata practically impossible to manage and earning it a top ranking on the California Invasive Plant Council’s list of the most notorious weeds.
If you do come across jubata grass seeds in a nursery, avoid them at all costs and opt instead for Cortaderia selloana.
Though still technically an invasive species, Cortaderia selloana can be controlled with some effort and is the one variety that offers those gorgeously fluffy plumes and handsome charm.
3: Choose Colors to Match Your Garden Design
Though typically known for its soft, creamy flowers, pampas grass also grows in a gorgeous silver-pink color.
It’s no secret pampas grass is famous for its white plumes, but you should know that also Cortaderia selloana can also be grown in a gentle pink color, creating a unique look to your space.
With that in mind, consider whether you want the pink variety to add a dash of color or the famously fluffy white plumes that add that wild and windswept look.
4: Give Your Grass Plenty of Room
If you’re planning to grow multiple pampas plants, then a small garden really isn’t the place to do it.
Because they grow so abundantly, it’s best to plant each one roughly six to eight feet apart from one another to give it plenty of room to grow properly.
When pampas grass is planted too close together, it tends to grow in a knotted mess that serves as an ugly blight in your otherwise gorgeous garden.
5: Plant Your Pampas Grass in the Sunniest Part of Your garden
Pampas grows best when it recieves lots of direct sunlight.
Pampas grass is an incredibly tough plant that adapts well to most environments, but it definitely prefers bright, sunny spots.
As such, experts recommend that you choose a spot in your garden that gets at least six hours of direct sunlight per day.
Sure, your plant will still grow in partial shade, but it won’t grow as well and will become more susceptible to disease.
So, as a general rule, the more sunlight your grass gets, the better.
6: Plant Your Grass Away from Fire and Neighbours Gardens
Finding a sunny spot will certainly benefit your grass, but there are other important factors that you’ll also need to consider when it comes to choosing the right location for your new pampas.
This is a highly flammable plant we’re dealing with, so growing it in an area where you also keep your grill, barbeque or firepit is ill-advised.
Likewise, keep in mind that if your pampas does set alight, the fire will spread pretty quickly, so it’s best to keep it away from structures such as bird tables and patio furniture that could also catch fire.
On a different note, consider the self-sewing nature of pampas grass. Wind can carry pampas seeds for miles and they’ll grow -or at least attempt to grow- wherever they land.
As such, reduce the risk of your neighbors’ gardens becoming overrun with pampas by growing it as far away from them as possible.
7: Plant Seeds in the Spring for Best Results
Cortaderia selloana thrives in warmer climates and does best in the United States Department of Agriculture’s plant hardiness zones seven to eleven.
With that in mind, you’ll find that early spring is the best time to plant pampas grass seeds in a garden.
As the temperature rises, the grass begins to flourish, producing those tall, 10 – 13ft plumes within a few months so that you can enjoy the full effect of your ornamental grass by the summer.
Before then, you can add preparing the seedlings onto your list of gardening tasks for the winter months.
Potting the seeds in your greenhouse gives them ample opportunity to germinate and develop into hardy seedlings which will produce better results once transferred to your garden.
8: Pampas Grass Prefers Well-draining Soil
Getting the right kind of soil is vital to successfully growing pampas grass. Chose a well-draining option for best results.
It may sound obvious to some, but so many inexperienced gardeners underestimate what a big difference the right kind of soil can make to the long-term health of plants.
Some plants flourish in different types of soil than others so, while you may be able to get away with planting your pampas in whatever ground you happen to have in your garden, you’ll have a better chance of success if you prepare the ground properly first.
Pampas grass prefers well-drained, fertile soil like Burpee’s Natural Organic Premium Growing Mix, though it’s certainly possible to add other ingredients to your existing soil to create a fertile ground in which your grass to grow.
With damp, heavy soil, try adding some lightweight compost mix. If you have dry, thin soil in your garden, mix it with plenty of substantially rotted organic matter such as bark mulch.
9: Use Quartz Sand to Prevent Water-Logging
Another excellent ingredient to consider adding to your soil is quartz sand.
We prefer the natural, chemical-free sand from FairmountSantrol, though any natural quartz sand will suffice.
If you live in a region that receives a lot of rainfall, this inexpensive mineral will prove invaluable in preventing water-logging which would otherwise damage your pampas.
10: Water Immediately After Planting
Use a hose to spray your grass with plenty of water immediately after growing.
There are some types of plants that require almost no watering once planted in the soil. Pampas grass is not one of them.
Once the seeds have been sewn, reach for your hose pipe and water deeply straight away.
Though you won’t have to water your plant often, giving it plenty of water to begin with will certainly aid growth.
11: Cut Back on Watering as Your Plant Grows
Pampas grass is incredibly drought-resistant. As such, some gardeners will tell you that there’s no need to ever go near it again with that hose pipe after the initial watering.
Offering a counter-argument, others insist that it is best to water your grass every few weeks for the first few months to ensure that the soil is evenly moist.
Once your plant fully establishes itself and starts to take off, you put that hose away and let the natural rainfall give your grass all the moisture it needs.
In cases of extended periods of severe drought, feel free to go back to watering so that your grass remains healthy.
12: Create a Plan for Managing Your Pampas Grass Growth
Though it may be beautiful, pampas grass requires a lot of work, so create a workable plan to maintain it.
Just in case we hadn’t hammered this point home enough, here it is again:
Pampas grass takes a lot of work to manage.
With that in mind, it pays to think ahead about how you’ll take care of your grass once it starts to take over your garden.
Mark out time in your gardening calendar to trim the grass back and prevent it from getting too out of control.
Should your grass grow in abundance, you may find it helpful to recruit a friend to help you with the trimming and pruning process.
13: Prune Every Year to Keep Grass Under Control
Pampas grass grows rapidly and excessively so, when it comes to maintenance, a quick five minutes with your favorite pair of hand shears isn’t going to cut it.
Instead, break out a pair of good-quality hedge shears and cut the plant grass down all the way to the ground.
In our experience, mid-February to late-March is usually the best time to do this, but there’s no reason why you have to leave it until then if your grass is clearly getting beyond control.
Technically, it is possible to burn the plant all the way down to the ground, but given how flammable it is, this is only recommended if you’re certain you can keep the fire contained.
14: Take Extra Care When Pruning
On a similar, safety-related note, beware that the grass has sharp foliage which can cause some pretty nasty cuts and scrapes.
When it’s time to prune, keep your skin protected by a long-sleeved shirt and a pair of thick gardening gloves.
15: Propagate in Late-Winter/Early Spring
After around five years, Cortaderia selloana’s center begins to slowly die out, resulting in minimal new growth and plenty of ugly, dried out leaves.
To keep it fresh and alive, the grass can be propagated as early as September, though you’ll get better results if you wait until the early part of the following year as the end of winter transitions into the start of spring.
A period after the last forecasted frost but before new plants start to grow is the optimum time to ensure that your grass has an entire season to recover from propagation and re-establish its roots.
To propagate, cut the grass all the way back so that you can see the base.
You’ll see that the central clump of grass will be dying out (or may already be dead), but that it will be surrounded by baby shoots which are still healthy.
Using a sharp spade, cut into the clump to separate these healthy shoots from the dead clump, then discard the clump.
Replant the younger growth at the same depth that they were at when they were attached to the main plant.
Then, just as if you were growing pampas for the first time, feed it a decent amount of water and continue to ensure that the soil is evenly moist until the new plant is established.
15: Combine With Other Grasses and Shrubs for a Stunning Garden Design
Red Twig Dogwood like this makes a perfect companion plant to pampas grass.
We all know how striking Cortaderia selloana looks on its own, but its aesthetic qualities can be greatly enhanced by mixing it with other ornamental grasses and shrubs.
The contrast between the soft, gentle whites of pampas and the bold colors of Red Twig Dogwood, for example, can create some truly eye-catching results.
Other recommended companion plants for pampas grass include Tall Verbena, Autumn Joy, Fountain Grass, and Forest Pansy.
Pampas Grass Frequently Asked Questions
Pampas grass like this can grow to over 10 ft in height, usually taking between 2 – 4 years to reach full maturity.
How Fast Does Pampas Grass Grow?
Cortaderia selloana does not take long to grow. From seed, the plant reaches full maturity within two to four years and generally lasts for around fifteen years.
A perennial, pampas grass germinates during the spring months and produces bulbs within the first year. Once winter comes, the plant tends to become dormant before starting to grow again the following spring.
After just one growing season, the center clump will begin to die, but the plant itself will expand as younger, healthy shoots emerge.
It’s at this point that you should consider propagating your plant to keep it healthy and promote growth.
How Tall Does Pampas Grass Grow?
Pampas grass is renowned for its height, though how tall it actually grows will depend largely on its environment.
At a minimum, expect your grass to grow to around five feet tall, though it’s much more likely that, at full maturity, it will reach somewhere between 10 and 15 feet.
Is Pampas Grass Toxic?
The American Society for the Prevention of Cruelty to Animals states that Cortaderia selloana is non-toxic to dogs, cats, and horses, but what about humans?
Research shows that pampas grass is relatively harmless, though most experts do warn that ingesting any plant can potentially lead to adverse effects such as allergic reactions.
So, while it’s a safe plant for gardener owners with children or animals, it’s still wise to ensure that children especially understand that your pampas aren’t a snack.
Does Pampas Grass Need Fertilizer?
Pampas grass doesn’t require fertilizer and grows perfectly well without it. However, some gardeners choose to use a balanced fertilizer like Grow More’s All-Season’s Plant Food to encourage regrowth after pruning.
How Can I Get Rid of Pampas Grass?
Killing pampas grass once and for all takes some work, but it can be done.
The easiest method is to use a post-emergent herbicide. The popular Weed & Grass Killer Concentrate Plus from Roundup is particularly effective, though any brand you can find that contains Glyphosate and Haloxyfop will do the trick.
Before applying the herbicide, you’ll need to trim your grass right back. Again, be sure to wear protective clothing such as long-sleeved shirts and gloves to prevent nasty cuts, then use a pair of heavy-duty shears or, better yet, a good quality weed eater, and hack the grass right down to the route.
This has two benefits:
1: It allows you to use less herbicide, which is better for the environment.
2: When the grass is cut, it begins absorbing nutrients from the ground in order to regrow. This increases the amount of herbicide it will absorb.
Once cut, follow the instructions on the bottle to ensure you have the right water-to-chemical ratio and apply it.
Larger plants will likely take two or three applications before they properly die.
Once done, you can either leave the grass where it is to rot, or pull it up and dispose of it.
What are Some Non-Chemical Alternatives to Killing Pampas Grass?
Digging up the roots can be a natural way to remove pampas grass without using chemicals.
If you don’t like the idea of using herbicides, there are some natural methods of pampas grass control that you can use.
One simple yet time-consuming method is to use a tarp. Cut the plant down to the ground then cover it up with a thick tarp. This prevents any light or moisture from getting to the plant, meaning it will eventually wither and die.
Be warned though, this is not a quick-fix method. It will likely take weeks, perhaps even months, before your grass actually dies.
Cortaderia selloana is fairly resistant to salt, but if you apply enough of it, say between five and ten pounds, then it will kill off your plant.
Some people recommend burning as a quick and easy method of removing pampas grass, but there’s one problem with that:
The burning only encourages future growth, and your grass will be back, taller than stronger than ever, the following year.
Instead, a much more thorough, though labor-intensive, method is to break out your shovel and dig out all those roots. It’s hard work, but it guarantees that your grass will be gone once and for all.
Pampas Grass: Is the Effort Worth it?
As you can see, getting rid of pampas grass isn’t exactly an effortless undertaking. So, if you do decide to plant it, you really only have two choices:
1: Be in it for the long-haul and have pampas grass growing in your garden for years to come
2: Put in some serious work to get rid of it and risk damaging your garden.
After all, if you decide to kill off your plant using herbicide then you run the risk that the chemicals will spread to other plants that you want to keep and ultimately kill them off as well. If you go the natural route and use salt, then that salt can stay in the ground even after you’ve removed the pampas roots and make the soil unsuitable for planting anything else in the future.
With that in mind, taking care of the annual pruning process, though still hard work, is generally the easier option.
But is it worth it?
In our estimation, yes, absolutely.
Despite the hard work involved, no other type of ornamental grass creates the same sense of dramatic beauty as pampas grass. With tall, feathery plumes blowing gently in the breeze, Cortaderia selloana really does make a splendid addition to any garden, especially when used as a border or to add form to a larger space.