Tag Archives: ornamental grasses

Pruning Ornamental Grasses

Who doesn?t love a garden filled with the movement and beauty of ornamental grasses especially during the fall? But how do you take care of them after the show is over for the season?

lomandra
Lomandra and NZ flax in mixed planting

When I recently received an email asking what to do with an ornamental grass that had already turned that soft tawny color I figured it was time to brush up on how to care for them. To prune or not to prune? That is the question.

Grasses are distinguished from other plant families by their growth habit. They grow upward from the base of a leaf or shoot and can regrow from the crown when cut back. True grasses generally have extensive root systems which help control erosion. There are other grass-like plants like chondropetalum, New Zealand flax, kangaroo paw and lomandra that resemble grasses in their growth habits and are often some of the best companions for interplanting with grasses.

Most grasses require little care, minimal fertilizer and only occasional grooming. Some flourish with just enough water to meet their needs while others need regular irrigation. Diseases and insect pests are rare and they are not attractive to deer. They have succeeded because of their adaptability and have evolved to suit almost every environment and climate on earth.

japanese_blood_grass
Japanese Blood grass – small and goes dormant

Basically, grasses and grass-like plants fall into 4 different pruning types: Large or small types that go dormant and large or small types that stay evergreen.

Large grasses that go dormant such as miscanthus and calamagrostis are pruned yearly in late fall to late winter. It?s best to hold off on pruning as long as possible to preserve the winter interest and to provide food for birds. When they turn brown and start shedding it?s time to prune. Gather the blades together with a bungee cord or rope and cut down to 10 inches.

Small grasses that go dormant such as Japanese blood grass or fountain grass should be pruned yearly at the same time. Don?t cut them too close to the crown or you risk losing a few clumps. Cut those under 3 feet tall down to 3 inches and those that grow taller down to 6 inches.

guardsman_flax
The Guardsman- NZ flax large & stays evergreen

Large, evergreen grass-like flax and cordyline can be pruned anytime to cleanup and resize but rejuvenation should be done mid-spring. When pruning to freshen up the foliage, select the most damaged leaves and cut them out at the base. If your plant is overgrown or suffered winter damage, prune severely in mid-spring cutting off all the foliage at the base. Tall cordyline varieties can be cut off a few feet from the ground and they will re-sprout below the cut or from the base.

Lastly, small evergreen grasses like carex, acorus, blue oat grass and blue fescue grass can be cleaned up in spring by putting on rubber gloves and combing through the grass. If this kind of cleanup isn?t enough you can reduce the height by two-thirds and in a couple of months they will look good again.

Great Grasses for the Santa Cruz Mountains

Sawtooth Mtns
Sawtooth Mountains, Idaho

Recently I took a road trip to see some of our great country. The Sawtooth Mountains in Idaho and the Grand Tetons and Yellowstone in Wyoming have been on my bucket list for a long time. In addition to the amazing places I visited and the buffalo, elk and bald eagles I got to see up close and personal I was able to take a look at passing gardens of people who live in harsh climates and get some tips on plants that survive and thrive in these conditions. If you are looking for tougher plants for your own garden to add this fall planting season here are some ideas.

Some of these plants are old favorites and some are new. There?s a reason a plant is used over and over again. It?s reliable and trouble free. Plants that are have low water requirements are a must, too.

Throughout the small towns I passed through as well as larger ones like Jackson Hole, Wyoming I again and again

rudbeckia hirta
rudbeckia hirta

saw Karl Foerster feather reed grass planted in landscapes along with the Black-eyed Susan variety Goldsturm.

Feather reed grass tolerates heavy clay soil unlike many of the other ornamental grasses. Forming a clump only 2 feet wide it can fit in a smaller garden without overwhelming other plants. Even in light shade it blooms early in June with tight, vertical flower stalks of feathery, purplish-green flowers which turn golden as the sterile seeds mature in summer. Feather reed grass looks good throughout most of the winter providing interest until cut to the ground just before the new shoots appear.

Besides texture, grasses provide color for your garden, too. Who hasn’t admired the burgundy foliage of Red Fountain grass? it’s one of our most popular grasses with fox-tail like coppery flower heads. Eaton Canyon is a dwarf variety that is root hardy down to 20-25 degrees. Plant it in full sun and irrigate little to occasionally. Be sure to cut this grass back in late winter even if it hasn?t suffered much from frost. The new growth will look so much better for this treatment.

Another grass I?m hearing a lot of good things about is called Pink Crystals or Ruby grass. Melinis nerviglumis has pretty blue-green foliage that forms a one foot tall clump turning puplish-red in the fall. Very showy pink flowers rise above the foliage in the spring and summer. This grass will tolerate considerable dryness.

OLYMPUS DIGITAL CAMERA
Pheasant Tail grass

Grasses are survivors and are good choices for sunny spots that get little irrigation. Good drainage is a must for these plants so amend the soil with plenty of organic matter before planting. Combine drought tolerant grasses with companion plants and a few accent rocks to complete your dry theme. Good combinations for these areas are Pheasant Tail Grass with the sky blue flowers of Russian sage. Giant Feather grass looks great with the purple flowers of penstemon ‘Midnight’. If you like blue foliage, try ‘Elijah Blue’ fescue grass with Amazing Red flax for a show stopping combination. Pink Muhly grass will stop traffic when in bloom.

phormium_Guardsman
Phormium

Grasses are distinguished from other plant families by their growth habit. They grow upward from the base of a leaf or shoot and can regrow from the crown when cut back. True grasses generally have extensive root systems which help control erosion. There are other grasslike plants that resemble grasses in their growth habits and are often some of the best companions for interplanting with grasses. These include New Zealand flax, carex family sedges, chondropetalum, kangaroo paw and lomandra ?Breeze?.

Most grasses require little care, minimal fertilizer, only occasional grooming and just enough water to meet their needs. Diseases and insect pests are rare and they are not attractive to deer. They have succeeded because of their adaptability and have evolved to suit almost every environment and climate on earth.

Caring for Ornamental Grasses

rolling_hillsI’ve lived in California my entire life and have traveled on many a back road enjoying the scenery, the trees, the flowers, the birds. Discovering a new road, the road less traveled, is half the fun of any journey. It was close to sunset recently when I found myself on one of those roads. Actually I kinda got lost on my way to Aunt Rosemary’s house and ended up on the back side of Mt. Diablo. Serendipity, the occurrence of events by chance in a happy or beneficial way, was on my side.

With the winter sun skimming the tops of the rolling hills and a meadowlark announcing his presence in the row of walnut trees growing along the road I was reminded of the seasons here in the mild winter areas of California. The setting sun filtered through the grasses tawny in late fall. These grasses are just one of the many ornamental grasses that grace our gardens. With winter coming on, some go dormant, some are evergreen and some are deciduous. How should you take care of the grasses in your garden?

If your grass is big like a miscanthus and now sports that beautiful wheat color as it goes dormant, you can enjoy the show to provide structure to the winter garden as well as seed and cover for wildlife. Come February or early March, before new growth starts from the base, tie the stems into a bundle with twine or a bungee cord and prune down to 10 inches using sharp hedge shears or electric hedge pruning shears.

But what about those other grasses and grass-like plants? How do you keep them neat looking and fresh throughout the year?

If it’s small and goes dormant, like Japanese forest grass, Japanese blood grass or Fountain grass, you hakonechloa_winter.1600can prune them anytime now until early spring. I like to leave them to provide winter interest through the holidays but there will come a day in January when the winter storms will start blowing the leaves everywhere. Then I’ll prune the stems down to 3″ for the shorter grasses or 6″ for the taller fountain grasses. If I prune too low there’s a danger of cutting into the crown of the plant. Moisture then tends to settle into the crown and can rot them out.

Then there are the spiky grasslike plants like New Zealand flax or Cordyline that stay evergreen but can look ratty after a long, hot summer or cold winter. Prune these anytime for cleanup or size reduction, midspring for rejuvenation.

Select the oldest or most damaged leaves and cut them from the base out one by one. To control size, cut out ton more than 2/3 of he tallest leaves at the base. If your plant has severe damage and needs total rejuvenation wait until midspring and cut down to 1 foot. It will regrow in about 4 months but may need retrimming as the leaves grow out.

carex_oshimensis_EvergoldLastly, there are those small grasses that stay evergreen such as Blue oat grass, Pheasant tail grass, Acorus, Mondo grass, Carex, Mexican feather grass and Liriope. Like the flaxes, clean up can be done anytime but pruning for rejuvenation should be done early to midspring.

If your grass is looking a bit disheveled, comb out the old stems. Rubber gloves work great for this as the spent foliage clings to the rubber and comes out easily. If you need to go for the big chop to bring it back to its former glory, wait until early spring and cut back by 2/3. Cutting back too much will allow moisture to gather in the crown and cause rot. Rejuvenation pruning shouldn’t be done more than every 2-3 years as small evergreen grasses have less vigor than grasses that go dormant. Mexican feather grass is the exception and can be pruned back hard anytime its needed.

So that’s all there is too it. Decide if your grass is large and goes dormant, small and goes dormant or large and stays evergreen and take it from there for beautiful ornamental grasses year round.