The trend toward smaller spaces drives intensive use of perennials and grasses

The midcentury ranch house with the huge yard is a thing of the past. Replacing it is the tall house with a small yard — and that’s changing the shape of home landscaping.

Everywhere across the country, homebuilders are squeezing as many new homes as they can onto shrinking parcels — but one need look no further than the rapidly urbanizing hills near the southwest Portland, Oregon suburbs of Beaverton and Tigard.

Massive Mountainside High School opened its doors last fall, taking the place of sprawling apple orchards. Former agricultural land that once grew acres of blueberries, hazelnuts and azaleas is now filled with condominiums, three-story skinny homes and McMansions. Spaced less than two feet apart, they often lack backyards, and their ever-shrinking front yards are often managed by a homeowners’ association.

It’s the same story in other cities. Whether driven by rulemaking, land availability or other factors, developers are building homes taller and closer together, essentially changing the character of single-family neighborhoods and landscapes.

The typical approach to newly installed landscapes has been to leave spacing between shrubs, grasses and perennials. This results in expansive open areas where weeds can take hold. But for these densely packed homes, there’s a more logical approach: layering plants and filling up small spaces.

Landscape designer Vanessa Gardner Nagel, Seasons Garden Design owner and author of Understanding Garden Design: The Complete Handbook for Aspiring Designers, is based out of Vancouver, Washington. She has used the layering approach on several projects.

“By covering the ground with perennials, grasses, shrubs, and trees in dense plantings, (you can) minimize weeds,” she said.

Low maintenance and no maintenance

There are several ways to plant densely. One approach is to adopt the relatively new concept of “plant communities.” The idea falls somewhere between traditional landscaping — using plants available in the trade, and natural landscaping — that makes use of prescribed natives for a specific area.

A plant community makes use of plants that naturally live in harmony, but arranges them more formally than one would see in nature. Nagel expects to see this concept gain traction, as botanists learn more about how plants work together.

According to Nagel, more and more homeowners prefer landscapes mixing nativars and edibles with grasses and perennials. For example, she has used Pycnanthemum interspersed with broccoli and low groundcover sedge Carex siderosticha ‘Variegata’.

Designers and homeowners alike use grasses and perennials to remind them where bulbs are hiding. “Carex ‘Frosty Curls’ reminds me where my Eucomis ‘Sparkling Burgundy’ are situated,” Nagel said.

For her clients, Bouteloua gracilis ‘Blonde Ambition’ was wildly popular last year. She thinks Molinias and Seslerias are becoming more popular as low-growing groundcovers among perennials like hardy geraniums.

Containers for small spaces

In small yards, intensive container gardens are an appealing option. Dee Montpetit, outside sales manager at AW Pottery Northwest, recommends planting a single grass in a statement container. Uncinia rubra’ Firedance’, Red Head Fountain Grass (Pennisetum alopecuriodes), or Japanese Forest Grass (Hakonechloa macra ‘Beni Kaze’) were all listed in the Great Plant Picks Best Plants for Containers poster released at the 2018 Northwest Flower and Garden Festival in Seattle.

Also attending the festival was Butchart Gardens, the famous botanical destination in Victoria, B.C., Canada. They displayed stunning silver and chocolate combinations for containers or small landscape beds at its booth.

The garden’s landscape designer commingled Silver Leaf Astelia chathamica ‘Silver Shadow’, ruby-leaved evergreen shrub, Lophomytrus ralphii ‘Kathryn’, Helleborus x ballardiae and Heuchera d. ‘Black Ice’.

Nagel’s new favorite vessel combination includes Helleborus, Mahonia ‘Soft Caress’, Heuchera, Viola, Euphorbia ‘Ascot Rainbow’ and Carex ‘Everillo’. She adores commingling Hebe ‘Karo Golden Eck’, blue fescue grass, velvety gray-green Salvia pachphylla, with a skirt of black mondo grass and Epilobum latifolia ‘Calistoga’.

Bobbie Schwartz, is a perennial expert, designer, and author of the new book Garden Renovation: Transform Your Yard Into the Garden of Your Dreams. She loves blending Koeleria glauca ‘Tiny Tot’, a cultivar of blue hair grass known for short foliage with Sedum ‘Angelina’ and Sempervivums for drought-resistant container arrangements.

Hardiness matters

For a successful landscape in a small yard, every plant must earn its space, and that means testing and trialing is important for growers, designers and homeowners alike.

Phil Thornburg, the owner of design firm Winterbloom Inc. who has been featured in more than six regional and national magazines, tests plants for three years before using them in his clients’ landscapes. “We only use plants that last up to 10 years in our clients’ landscapes,” he said.

Schwartz agreed. “I am very reluctant to plant anything I’ve haven’t trialed,” she said. “When and if I do, I always let the client know that I’ve read about it but have not trialed it.”

Nagel also agreed. “As a designer and as an industry, it’s important for us to trial new plants thoroughly before putting them on the market or in clients’ gardens,” she said.

Designers become frustrated when breeders and wholesale nurseries push new varieties out and expect them, their clients, and the consumers to be the guinea pigs.

The most challenging plants for designers are the latest Heuchera varieties. Gushing over new colors and textures, most designers trial and test named varieties, seeking cultivars that can survive rough-and-tumble living in multi-use gardens.

“The more exotic colors and leaf patterned varieties look good and perform well in pots and baskets, but cannot handle living in the ground,” Thornburg said. “When planted during a mild winter, heucheras grow really big and push things out of their way. During a cold winter snap, they either disappear or end up severely damaged, resulting in our team needing to utilize several plants to replace one.”

“Tissue culture cultivars are fine,” Schwartz said. “With Heuchera, I tend to use only those cultivars that have villosa
in them because they are stronger than other species.”

Nagel and Thornburg agreed heucheras shine in containers. “I’ve had better success with heucherellas in the ground. If deer find them, they seem to like them as long as the leaves are young,” Nagel said.

Putting it all together

Homeowner preferences vary, even when they have a small space to work with. Some of them just want to “plant stuff and let it grow,” Thornburg said, while others are very specific.

“Today we are working with a client who wants 50 percent boxwoods,” he said.

Designers, on the other hand, have favorites. And when it comes to small spaces, those preferences are carefully chosen. “Grasses and perennials are probably 75 percent of the plants in my designs,” Schwartz said. “I spec 75 percent perennials and 25 percent grasses, always making sure that their cultural requirements are similar.”

“All of my designs contain grasses and perennials, occasionally as much as 80 percent of a design,” Nagel said. “They are a very important ecological component.”

Landscape designers work with contractors and plant brokers to find the best match for the project, client and design. “We do not push any particular kind of plant over others,” Thornburg said. “We avoid plants which are invasive or have death wishes.”

Blooming Nursery, a wholesale nursery in Cornelius, Oregon, sends hot sheets of plants that are looking great featuring weekly lists of what’s available. Their sales reps visit independent garden centers to showcase plants that may be a novel idea for their buyers.

Blooming recently launched a new mobile app for landscape designers and brokers who can quickly build quotes on demand. Grace Dinsdale, president of the nursery, invested in the software so their customers can scope out inventory and prices in real time.

Favorite combinations

Asking designers what their favorite perennial and grass combination is akin to asking a parent who their favorite child is.

Schwartz has a long list. For rain gardens, she leans towards Eragrostis spectabilis, Sesleria autumnalis, and Lobelia cardinalis. She saw this combination used in an Annapolis suburb rain garden where stormwater runoff is a huge problem. “Keeping it from draining into the Chesapeake Bay tributary on which this home is located was critical,” she said.

For vertical gardens, Schwartz loves the combination of Perovskia and Calamagrostis ‘Karl Foerster’ at the St. Louis World’s Fair Pavilion. “It is designed the traditional way with blocks of color, Schwartz said. “If it were being designed today, the plants would weave in and out of each other.”

Schwartz loves the inflorescence of Molinia caerulea ‘Skyracer’ in front of Rudbeckia subtomentosa ‘Henry Eilers’. “Although the Molinia is taller when in bloom, the foliage is only two feet high,” she said. She plants it at the front front of borders and Rudbeckia in the back as it crests five feet tall — even before it blooms.

For a partially physically impaired client who did not want to install irrigation, Schwartz co-mingled Helictotrichon, Perovskia, Pennisetum, Panicum ‘Northwind’, Ajania pacificum, and Sedum ‘Angelina’ for the perfect xeriscape design.

The favorite grass used by all three designers were an even tie between black mondo grass Ophiopogon ‘Nigrescens’ and EverColor Carex ‘Everillo’. It keeps its color even in heavy shade but can also take a fair amount of sun.

Thornburg relies on black mondo grass where a grassy texture is essential in the landscape. “It’s tough, likes wet winters and smiles at the cold,” he said.

Nagel agreed. “Black mondo grass is the James Bond plant-tuxedo refined,”

Thornburg is fond of any of the pseudo grasses, Carex in particular, mixed with euphorbias. Carex testaceae and Euphorbia rigida make a good combination.  Calamagrostis ‘Karl Forester’ goes well in a combination with any variety of Rudbeckia or Echinacea as a surrounding sweep.

In the landscape, Schwartz loves mixing blue switch grass Panicum virgatum ‘Northwind’ with Helenium ‘Mardi Gras’, Eupatorium fistulosum or E. purpureum, and Verbena bonariensis. “This is a late summer combination, although the Verbena will start blooming when it gets hot”, Schwartz said. “All varieties are tall, so I place them at the back of a border or as part of a stylized prairie/meadow design.”

Nagel prefers Bouteloua ‘Blonde Ambition’ and Yucca filamentosa ‘Bright Edge’ for sunny, dry sites. On the flipside, for sunny and moist sites, she combines Molinia caerulea ‘Variegata’, Sanguisorba ‘Korean Snow’ and Iris siberica. For moist and well-drained part shade combinations, she likes to feature Hakonechloa macra ‘Albo Striata’, Brunnera m. ‘Variegata’, Helleborus Winter Jewels ‘White Pearl’ and Fuchsia ‘Hawkshead’.

Designs of the future

As with any design, the regional and local conditions are important to consider. “It’s important to consider what works in the Pacific Northwest as opposed to Europe, East Coast, or Midwest prairie,” Nagel said. “What we see others doing doesn’t necessarily apply to us. Our approach should be an interpretation that suits our climate and growing conditions.”

Designers, breeders, wholesale and retail nurseries all need to apply their collective creativity with regards to homeowners and shrinking footprints. Intensive plantings mixing grasses, perennials, shrubs, edibles, mini-me trees and conifers are the wave of the garden future. Increased demands for xeriscape designs to avoid irrigation cost and awareness of the environment and rain will become more prevalent.

Dawn Hummel is the owner of BeeDazzled Media LLC, a firm specializing in marketing for small B2B horticulture and floriculture customers. Hummel has more than 20 years of experience in retail garden centers and wholesale nurseries. She can be reached at [email protected], (503) 784-0691 or www.beedazzlemedia.com.

Download a PDF of this article

 

---

Read the next Greenhouse Issue article:

An illuminating trend | Greenhouse Issue 2017 | Greenhouse Issue 2016