Category Archives: Pollination

How About A Hedgerow?

With fall planting season upon us, Jeanie Taylor encourages us to consider a hedgerow.

By Jeanie Taylor

Don’t say you don’t have room for a hedgerow! You can grow a hedgerow even on an urban lot—atop a rockery, along the fence line, or in your parking strip.

What is a hedgerow?

Hedgerows traditionally were used as fences between fields. A “laid hedge” in England contained thorny plants like hawthorn to act as a barrier. Each tree or shrub was cut through the lower trunk and laid over, each one crossing the next—this living fence was maintained by a hedger. The hedger would do this hand work during the winter, and it was an actual full time job in days gone by.

Man leaning over bare branches of hedge

Photo courtesy of the UK National Hedgelaying Society

When the plants put out new branches, they would form a prickly barrier to keep livestock in and presumably other people’s animals, or perhaps predators, out. Wildflowers and herbs would sprout up in and among the hedge. Birds that perched and dropped berries and seeds below aided this process, especially as they helpfully packaged the seeds in poop to provide nutrients.

Hedgerows provide ecosystem services

While hedgerows still can provide a good barrier, the great thing about them for native plant lovers is the diversity they provide. Pollinators, predatory insects, and lots of animals and plants can find refuge there. There are fringe benefits like clean air and water, pest control, fertile soil, and pollination when we offer wildlife a good home.

These benefits – ecosystem services – hold the world together. An example of an ecosystem service is clean water: as water is filtered through layers of leaf litter and soil, microbes in the soil remove pollutants, organic matter helps hold water and release it slowly to nearby streams and lakes and prevents flooding. A healthy soil contains roots, plants, and animals that feed these important microorganisms and keep the food web of the soil intact.

Hedgerows provide habitat

Not only good habitat, but connected habitat, is the key to survival for plants and animals. Wilderness and managed reserves are the highest quality wildlife habitat, but the space in between that we humans take up with cities, towns, and agricultural land is a much more common feature of the overall landscape.

Because our human spaces stretch across so many boundaries, it becomes essential to manage this matrix (a bit of jargon that neatly sums up the areas where humans build, farm, work and travel) to ensure the integrity of the safety net that keeps us alive.

This was the topic of a 2011 article by Jim Robbins in the New York Times that covered a research paper documenting the toll of habitat loss in matrix lands:

Every fall the calliope hummingbird, which weighs about as much as a penny, braves high winds and bad weather to migrate from Canada and the northern United States to as far south as Mexico, then back again in the spring—a total of 4,000 to 5,000 miles.

The journey is one of several dozen “spectacular migrations”—in the air and on land —that are chronicled in a new report by the Wildlife Conservation Society…But the report warns that these migrations are in peril.

As migration routes are disrupted, other species can be affected too—including humans. Take the case of migratory songbirds, whose numbers are down across North America.

In the spring, these birds eat 3,000 to 10,000 tons of insects each day as they travel. “It’s a legitimate concern,” said Dr. Wilcove, of Princeton. “Presumably with the decline of songbirds, insect damage to crops and forests could be worse.”

From:  For Many Species, Moving Day Has Added Stress, by Jim Robbins

Clearly, we can and must pay attention to how we live with nature, which is not “out there”, but here where we are.

Blue-gray bird perching on tree trunk

Red-breasted Nuthatch (Sitta canadensis)
Photo courtesy of Kelly McAllister/WDFW

What’s needed? The best case is that there will be some connected places everywhere that afford essentials for wildlife:

  • food
  • water
  • shelter and resting places
  • places for homes

Hedgerows are ideal habitat to give insects, birds, and other beneficial wildlife places to find all these things. They create balance in the landscape and give you a chance to enjoy the diversity of life on earth.

Hedgerows make a difference

Planting hedgerows is something we can all do to make a difference. If you link yours with your neighbor’s you have an even larger habitat that is more than the sum of its parts. And hedgerows can be any size—even a few shrubs will improve things.

  • Hedgerows can be groomed or left to grow on their own.
  • The best ones contain a diversity of plants native to your local area, of varying heights, and with different bloom times.
  • Evergreens are exceptionally useful to wildlife and help prevent erosion and excess runoff year-round.
  • By choosing the right plants for the space, you will not need to control the growth of your hedgerow unless you want to. Depending on plant choice, they can be wild or groomed.

It’s easy to plant a hedgerow. When I gardened in Seattle, I planted one by putting in ‘way more vine maples (Acer circinatum) and red flowering currant (Ribes sanguineum) than necessary. Also lots of bleeding heart (Dicentra formosa) and other herbaceous plants and ferns (Polystichum munitum, Polystichum braunii, Asplenium trichomanes, Penstemon sp., etc).

I pruned it for shape, but not much else. The birds loved it, insects galore, and it made a nice wall to an outdoor room in the backyard.

Favorite hedgerow plants

Here are my favorite hedgerow plants. The five-star ones for urban areas are visually pleasing at during two or more seasons, evergreen, produce flowers and fruit for wildlife, don’t need a lot of pruning; when they do, it’s a quick job of selective cuts and you don’t have to constantly shear them to keep them around 6-8 feet tall. However many can be sheared with impunity if that’s your thing. If you use hand tools and compost the trimmings, that can be sustainable.

Four favorite hedgerow plants – all evergreen

  1. California wax myrtle (Morella californica). It’s only native from mid-coast south in Oregon, but it transplants beautifully to many parts of the northwest.
  2. Silk tassel tree (Garrya elliptica). Native to central and southern Oregon, it transplants well anyplace west of the Cascades. Can get very wide and tall, so best in a spot with lots of room.
  3. Evergreen huckleberry (Vaccinium ovatum). This shrub is slow growing, but exceptionally nice. Hummingbirds will like it!
  4. Tall Oregon grape (Berberis aquifolium). Yellow flowers provide great late winter/early spring nectar for pollinators and fruit for birds (and jelly!).

Trees and large shrubs

Depending on your available space, trees make a nice over-story component. Most native evergreen trees grow very tall, and for this reason may not be the best choice for a city hedgerow. Smaller deciduous trees and large deciduous shrubs (10–30 feet tall) that provide flowers and fruit can be mixed in among evergreens for diversity. Here are a few:

  • Vine maple (Acer circinatum). This deciduous favorite tolerates a good bit of sun or shade and provides some of our most reliable fall color. (See the Botanical Rambles profile of vine maple)

    Tall shrub with red berries

    Red elderberry (Sambucus racemosa). Photo by Ben Legler; all rights reserved

  • Red or Blue elderberry (Sambucus racemosa or S. caerulea). The elderberries need some care with pruning, as they will sprout aggressively at the cut. However, you can cut them to the ground in late winter and have a nice shrub the following year. Best in sun, but red ones can take part shade.
  • Viburnum (Viburnum edule, V. opulus, V. ellipticum) Also likely to sprout aggressively at a cut, so be cautious pruning these shrubs. Cut low and to a main branch if at all. Prune after all leaves are fully expanded, or if cutting to the ground, late winter. You will then need to choose which of the many sprouting stems to keep so they grow straight and strong.
  • Red-twig dogwood (Cornus sericea). This shrubby dogwood sports red twigs in winter, white flowerheads in spring, and clusters of berries (for birds, not people) in summer. See pruning info for elderberry and viburnum.
  • Silk tassel (Garrya elliptica). As mentioned above, silk tassel could qualify as a small tree because of its height. Be cautious when pruning, although as a hedge plant its tendency to put out many resprouts could be a benefit.
  • Black hawthorn (Crataegus douglasii). English hawthorns were one of the original English hedge plants. Here, those are a weedy species to avoid, but our native Crataegus douglasii is very nice. You can’t hurt them and they can be cut any which way, although you should hew to good pruning technique to avoid too much shrubby growth.
  • Serviceberry (Amelanchier alnifolia) Serviceberry is a deciduous, easy, shrubby tree that is loved by birds for the berries and insects for flowers. You could shear it, but a lower maintenance option is to let it grow, or cut it down to the ground every few years and let it resprout. (See the Botanical Rambles profile of serviceberry)

Slightly shorter (6-8+ feet) deciduous shrubs:

For shade: Goatsbeard (Aruncus dioicus), Indian plum (Oemleria cerasiformis). These are best mixed with other plants, as they disappear after blooming or become rather ragged as summer wears on. Outstanding pollinator plants.

For sun/part shade and a wetter spot: Hardhack (Spiraea douglasii), salmonberry (Rubus spectabilis), black twinberry (Lonicera involucrata), ninebark (Physocarpus capitatus), redtwig dogwood (Cornus sericea).

These are all plants that grow in ditches and along streams. Thus they tend to be in thickets, or to form thickets which are natural hedges, but if you have limited space, experiment gradually with them to see if they are for you. You may have to dig out runners or pull seedlings to keep them within bounds.

For the lower level of the hedge

  • Low Oregon grape (Berberis nervosa). Good for filling in, it’s height maxes out at around two feet tall
  • Sword fern (Polystichum munitum). Also good for infilling between shrubs, sword fern tolerates sun or shade. If you cut back old fronds in late winter as the new ones just start showing, they look tidier and fresher, but you don’t have to.
  • Deer fern (Blechnum spicant). If grown in shade and humusy, evenly moist soil, these ferns will reward an attentive gardener with smooth, evergreen foliage and interesting fertile fronds that look different from the sterile ones at the base.
  • Scouler’s polypody (Polypodium scouleri). This is another evergreen fern that is quite tough. It’s native to the outer coast, growing near salt water, clinging to cliffs. It makes a fine garden plant that’s small in stature and good for nooks and crannies. Somewhat sun tolerant.
  • Strawberries. Various strawberries can be sprinkled throughout a hedge. If you really want a solid mat, Fragaria chiloensis is your plant. Some of us gardeners find that it is over-used by landscape designers and a bit of a bully, as it spreads enthusiastically. In a hedgerow, or in a difficult, hot, sandy spot it would be an acceptable evergreen groundcover. Our other strawberries (F. vesca or F. virginiana) are less aggressive but may die down in winter depending on the temperature. (and see Botanical Rambles previous post on strawberries)
  • Fringecup (Tellima grandlflora). This plant is semi-evergreen, although you may not see much of it in the winter. It is a tough and endearing small herbaceous plant that will reward you in spring with cheerful flowers. Dragonflies will perch on the stalks after it has gone to seed if planted in the open, and it will re-seed itself generously. Somewhat sun-and drought-tolerant, but better with a little summer water or shade.
    Oregon sunshine (Eriophyllum lanatum) Photo by Ben Legler; all rights reserved

    Oregon sunshine (Eriophyllum lanatum)
    Photo by Ben Legler; all rights reserved

  • Kinnikinnick (Arctostaphylos uva-ursi). An evergreen groundcover that needs good drainage and a lot of light to thrive. Susceptible to fungus problems in damp, shady locations. If you see small swellings on the leaves, they are galls caused by insects and nothing to worry about. Plant galls are part of the ecosystem!
  • Oregon sunshine (Eriophyllum lanatum). A low-growing herbaceous plant native to grasslands, rocky cliffs, and open areas, this plant is attractive and cheerful. Foliage is a nice silvery grey. Needs lots of sun and good drainage. Can be cut back after flowering if it looks untidy (as can most other perennials). However leave a few seed heads for the wildlife.
  • Native grasses and sedges. Depending on the amount of sun and moisture available, there are native bunch grasses and sedges that will grow in open areas, light shade, and full sun.

Planting your hedge

Make a list of plants you want; try to have something blooming from late winter to late fall. Mixing in non-natives is perfectly fine!

Hedge plants can be planted more closely than when used as specimens in a landscape. You can jam shrubs together every 3–5 feet because the idea is to form a wall of foliage. You can repeat a pattern (3 of each species, 2-1-2, or whatever you think will look best).

Grouping plants of the same species together is good for pollinators because they can forage more efficiently and will be attracted to a massed group of one kind of flower.

Be mindful of sun exposure and make sure plants have the appropriate amount of sun or shade, especially if you are crowding them together.

You will need to water and weed them, mulch with compost, and take special care for at least 3 years. Once they are maturing and established, they will need less water and may only need an occasional deep soak every couple of weeks during the hottest months.

If something dies, that’s a chance to replace it with another plant that has done well for you. We have all killed plants in the trial and error process of learning what works. But remember that some plants (Indian plum for example) bloom very early, fruit, and spend the hot dry mid-late summer mostly dormant, so don’t mistake that survival strategy for death.

Lastly, you will find that when birds and other animals use your hedge, they will bring the noxious and invasive plants they eat elsewhere with them and deposit the seeds while perching in your hedge. Weed early and weed often for blackberries, English ivy, English holly, cotoneaster, spurge laurel and other nasty invasive plants. Find photos here.

For more on hedgerows, see Valerie Easton’s 2009 article in the Seattle Times: Hedgerows offer variety and shelter to urban gardens, Russell Link’s 1999 book, Landscaping for Wildlife in the Pacific Northwest, or check out the United Kingdom’s National Hedgelaying Society.

You can read more from Jeanie on her blog, Gopher Valley Journal. She has a chart of Pacific Northwest plants with information on size and characteristics at TaylorGardensNW.com.