As the temperatures start to drop and winter approaches, it’s time to start thinking about how to prepare your ornamental grasses for the colder months ahead.
These tough and versatile plants are a popular choice for adding texture and interest to any landscape, but they do require some special care to ensure they survive the winter and come back strong in the spring.
In this article, we’ll explore some tips and tricks for preparing your ornamental grasses for winter, including when and how to cut them back, how much water they need, and how to protect their roots from the cold.
So grab a warm drink, bundle up, and let’s get started!
How To Prepare Ornamental Grasses For Winter
One of the most important things to keep in mind when preparing your ornamental grasses for winter is that most established grasses need little additional watering except in periods of drought. This means that you can water grasses in containers only occasionally, since containers dry out so much. In winter, they likely need no more than monthly watering because the grasses need to remain dormant.
When it comes to cutting back your ornamental grasses, it’s important to note that most grasses go dormant in winter; those planted in the ground will survive with typical snow or rain. However, you can cut them back during winter to about 6′′to 12′′ height. This helps keep a bit of interest in the landscape and provides protection for roots, and helps anchor new shoots in the spring.
The fuller the ornamental grass is, the messier it can be when cutting it down. To lessen the mess, start by bundling the stalks. Wear gloves—some grass blades can be quite sharp. Any wide tape will do, as long as it’s sticky enough to adhere to the grass. Biodegradable paper tape is recommended for an eco-friendly approach. As an alternative, many gardeners like to use reusable bungee cords stretched tightly around the grass. Depending on the height of the ornamental grass, you might need to wrap each bundle of grass in two or three spots along the length of the stems. And especially wide plants might need to have their stalks divided into two or more sections before bundling.
Cool-season grasses tend to look good even as the weather cools. Leave their foliage in place until spring and then as soon as the snow is gone cut them back. Leave about 1/3 of the plant in place. Trimming cool-season grasses too harshly can irreparably harm the plant.
It’s important to note that most ornamental grasses develop tall seed heads late in the summer that naturally persist through the winter. When temperatures start to drop, the plant will die back, leaving the dried foliage, stalks, and seed heads. The general rule is that you should cut back the grasses before the next growing season, so that the new year’s growth will be more vigorous and healthy.
When To Cut Back Ornamental Grasses
Knowing when to cut back your ornamental grasses is crucial for their health and appearance. The best time to cut back ornamental grasses is in late winter or early spring, before new growth begins. This will expose the crowns to sunlight, reduce the spread of seeds, and eliminate habitat for undesirable animals and insects.
For warm-season grasses, once they turn brown, you can trim them back at almost any time. If you live in an area where fire can be problematic, trim warm-season grasses so they are just a few inches tall. However, if you live in an area where fire generally isn’t a problem, you can leave the dried grasses and seed heads in your garden for winter interest.
Cool-season grasses should be cut back in very early spring. As soon as the snow clears, cut the grass back by two-thirds, leaving one-third in place. Pruning too drastically can harm the plant. Some examples of cool season grasses include fescues, blue oat grass (Helictotrichon), tufted air grass (Deschampsia), and autumn moor grass (Sesleria).
It’s also important to note that most flowering grasses, including Calamagrostis, Miscanthus, Panicum and Pennisetum, are deciduous. Simply cut all the old growth back to the base at the end of winter – in late February or early March. Use secateurs, removing each of last year’s stems individually, and being careful not to cut off the new shoots that are emerging at the base.
In areas where wildfires are a seasonal concern, it’s recommended to cut back grasses in fall to lessen the threat of fire. You’ll know it’s time to divide grasses when a ring of living grass surrounds a dead center. It’s easier to divide most grasses when they are still short from their post-winter haircut so there’s no foliage to get in the way. This is also the best time to divide grasses that flower in late summer and fall. Use a sharp spade or root saw and separate the living portion of the grass into smaller sections. Replant the sections, water well and enjoy through the seasons.
How To Cut Back Ornamental Grasses
Cutting back ornamental grasses is a simple process that can be done with the right equipment. You can use handheld or powered hedging shears, a battery powered reciprocating saw, electric hedge shears, hedge trimmers, or even a chain saw to cut back your grasses. However, it’s important to wear gloves and long-sleeved shirts to protect your skin from any sharp edges.
To begin, start by wrapping a piece of rope around the outside of the grass and tie it into a tight column of foliage. This way, the grass will stay bundled as you prune and not explode into pieces everywhere. Once your grass is tied up, use your chosen equipment to cut the entire grass to about 10 inches tall. If you’re using powered hedging shears, it’s helpful to have a friend hold up the grass so it doesn’t fall on you as you cut.
It’s important to note that you should wait until the plants go fully brown before pruning, as long as you do so before they start growing again in spring. This preserves winter interest and provides food for birds. The grasses themselves will give you your cue. Maiden grasses start shedding soon after the new year, so as soon as you notice them making a mess, it’s time to prune.
Once you’ve finished pruning, plan to put down a fresh layer of mulch after you’re done pruning. This covers any tiny bits of grass that won’t rake up and provides nutrients to the soil, helps retain moisture, and prevents weeds from growing. It’s important to note that burning off the dead foliage is not recommended as it can cause damage or kill the plants.
Watering Ornamental Grasses In The Winter
When it comes to watering your ornamental grasses during winter, it’s important to remember that most established grasses need little additional watering except in periods of drought. This means that you can water grasses in containers only occasionally, since containers tend to dry out more quickly. In fact, most ornamental grasses won’t need extra water once they’ve become established, and after they’ve been in the ground for a year, you shouldn’t need to water them unless your area hasn’t had rain for more than 3 weeks.
However, if you live in an area that experiences prolonged periods of dry weather during the winter, it may be necessary to give your ornamental grasses some supplemental watering. The amount of water needed will depend on the grass species, the site, and on the quality, size and growth rate desired. If you do need to water your ornamental grasses during the winter months, be sure to do so sparingly and only when absolutely necessary.
It’s also important to note that if you are overwintering an ornamental grass in a pot, you should water those that are dormant sparingly. The plant needs its winter rest, so be careful not to overwater it. On the other hand, if you want to grow an ornamental grass as a houseplant during the winter months, you should water it regularly but not heavily.
In general, it’s best to avoid overwatering your ornamental grasses during fall and winter. Cut back on drip watering during rainy periods, and be sure to let the soil dry out between waterings. Most ornamental grasses go dormant in winter and will survive with typical snow or rain, so it’s important not to disrupt their natural growth cycle by overwatering them. By following these simple tips for watering your ornamental grasses during the winter months, you can help ensure that they stay healthy and vibrant throughout the year.
Protecting Ornamental Grass Roots From The Cold
During winter, it’s important to protect the roots of your ornamental grasses from the cold. If you live in an area with harsh winters, it’s best to move tender grasses in containers indoors if temperatures will dip below their threshold. For grasses planted in the ground, it’s best not to disturb the soil around the roots during winter. This will help protect the roots from damage caused by freezing and thawing.
One common mistake gardeners make is trying to force most perennial ornamental grasses to green up with frequent watering during winter. However, this can harm the plant and prevent it from properly resting during its dormant period. Instead, it’s best to let the grasses rest and avoid watering them too frequently.
If you have chosen a grass that can tolerate your average low temperature, it should come back in spring. However, if you notice any signs of damage or disease, it’s best to consult a professional for advice on how to care for your ornamental grass.
In most cases, you don’t need to cut back ornamental grass in fall; leave the dried blades on until late winter/early spring. This will help protect the roots and provide shelter for wildlife during the colder months. Once spring arrives, you can cut back the old growth and make way for new shoots to emerge.
In summary, protecting ornamental grass roots from the cold is an important part of preparing your grasses for winter. By avoiding excessive watering and leaving the dried blades on until late winter/early spring, you can help protect the roots and ensure that your grasses come back healthy and strong in the spring.