Coastal Landscaping Ideas for Shoreside Gardens

May 7th, 2009 · No Comments

Coastal Landscaping

While coastal climates vary greatly – from the rocky, windy coasts of Scotland, to the Florida
tropics, or to the warm and dry Mediterranean — most coastal areas do share common characteristics that can make landscaping a challenge.

Coastal landscaping problems

Along a shoreline, the forces of nature can be extremely harsh. High winds,
poor sandy soil, salt spray, and even salt water
overwash all affect the types of plants that will flourish in coastal landscapes.
Fortunately, there remains a wide selection to create a
beautiful landscape with and plants are one of the best methods of controlling
erosion caused by coastal forces.
Landscaping requires not only the use of tough plants, but also means creating a shelter for yourself, as well.

Plants for coastal landscaping: go native

The best way to get an idea of what will grow in your area is to look around local gardens and wildlands. This will not only tell you
what kind of plants will survive, but give you information about the conditions in general. If only a few hardy plants can be
found, such as American beach grass (Ammophila breviligulata), beach plum (Prunus maritima), bayberry and red cedar, then you know conditions are fairly harsh. On other sites with more shelter and better soils, even along the water, a varied mixture of healthy plants will reflect the larger
number of choices available.

Weeping lovegrass (Eragrostis curvula) is a bunch type perennial grass that can be seeded in sandy areas that are not
subject to blowing sand. Hardy to zone 7, it is adapted to poor, drought-prone soils and has an extensive fibrous root system that
stabilizes sand. In sterile dune areas or in areas with blowing sand, American beach grass is the best plant to use in
initial plantings. Beach grass can be planted in late fall and through the winter up until mid April. Shrubs such as bayberry
and rugosa rose can be used further back in the dunes once the beach grass has become established, since the beach grass
will protect the shrub stems from sand abrasion.

Plants that do well in most coastal area include Blolly (Guapira discolor), Chrsitmasberry (Lycium carolinianum),
Crabwood (Gymnanthes lucida), Golden creeper (Ernodea littoralis), Necklace pod (Sophora tomentosa),
Paradise tree (Simarouba glauca), Blackbead (Pithecellobium guadalupense), Maidenbush (Savia bahamensis),
Biscayne prickly ash (Zanthoxylum coriaceum), Beach cocoplm (Chrysobalanus icaco), Seven-year apple (Genipa clusiifolia)

Improving sandy soil

A dry, permeable, sandy soil condition is one of the biggest problems coastal landscaping presents. This applies not only to
direct waterfront gardens but also to inland areas next to the coast. Sandy soils are typically dry and lacking in nutrients and
organic matter, so a generous amount of organic material should be added when preparing soil for planting. Compost, composted
manure or peat moss will make sandy soil better able to hold both water and nutrients. A minimum of a 3-inch layer of organic
material should be worked into the entire planting area — and the more would be better.
Plant trees and shrubs according

to the correct procedures: planting holes three to five times the diameter of the root ball
and no deeper than the distance measured from the trunk flare to the bottom of the root ball.

Defence from the elements: plant screens

Because wind and salt-spray are such constant features of the coastal landscape, plants must be tough to survive. When selecting plants for coastal
landscapes, keep in mind that few plants can survive the rugged conditions of full and direct exposure to the ocean. Careful planning can reduce exposure to these conditions. Plant screens can be grown to provide shelter for less tolerant plants. These living screens generally start with the low materials on the windward side and increase in height away from the wind. For example, rugosa rose (Rosa rugosa) and bayberry (Myrica pensylvanica) can be used to form a low, tough outer defense in areas other than the seaward side of the front dunes. Behind this, a staggered double row of evergreens, such as Japanese white pine (Pinus parviflora) or Eastern red cedar (Juniperus virginiana) will enhance the effect.

Once this screen is in place, it will shelter more sensitive plants while they become established. Remember to tie back
creepers to protect them from wind damage.

Landscaping on a sandy slope

Stabalizing any slope is hard enough, but when that slope is composed of shifting sand the
job can seem nearly impossible.
Even if the entire face of the bank has established plant growth on it, ground water seepage
can cause whole sections of the
bank to erode or slump. To control erosion, any bare spots on the slope should be filled with plants as soon as possible to
provide a coverage. Grasses, with their fibrous root systems, tend to be better as stabilizing plants then shrubs. However,
because shrubs can provide a canopy to intercept heavy rainfall, thus reducing erosion,
they work will in combination with
grasses. American beach grass can be used to stabilize the base of many slopes but can
only be used to the tide line.
Biodegradable fiber rolls (bio-logs), with clumps of beach grass planted in them, can be used to stabilize the toe of a bank,
allowing the upper bank vegetation to become established. In sheltered locations, salt marsh grass (Spartina patens) can be
used in the area between mean high and spring high tide lines. Saltwater cordgrass (Spartina alterniflora) can be used in
the intertidal zone. For barren banks, placing mulches, netting or erosion control blankets over seed grasses will stabilize
the young grass until it becomes established.

If the bottom of the slope is not stabilized, erosion of the bank will continue. When sections of a slope are broken down by winter storms, waves, heavy rains or wind damage, they must be repaired before additional damage occurs.

It’s usually futile to plant trees on the bank face as erosion or high winds will only pull them out again. Those trees that
are there should be pruned back to protect them from wind damage. Also avoid piling brush or debris on a bank.
Piled debris will not only not protect the slope from erosion and, in some cases, but can prevent stabilizing plants
from growing.

Buffer strips for coastline homes

For homes bordering the coast or a wildland area, maintaining a planted buffer strip between the property and the wild
area can control erosion from run-off coming over the top of and down a landscaped area. It will also provide wildlife
habitat and reduce human impact on the wild area or waterfront. A narrow vegetated buffer strip of five to ten feet wide,
planted along the edge of a resource area will reduce the effects fertilizer, insecticides, and other garden chemicals —
trapping pollutants and nutrients moving before they reach the water. Whenever possible, use native species when planting
buffer strips. No only do they blend better with the wild are, they also require less care.

Coastal lawn care

The same coastal forces that affect trees and shrubs will also impact the health of a lawn. In poor, sandy soils, a minimum
of six inches of topsoil should be applied before adding seeds or sodd. Choose seed
mixes that contain more turf grasses such as
chewing fescue, hard fescue and creeping fescue than Kentucky bluegrass in any seed mix or sod blend. These types of
grass will have a higher tolerance for dry conditions and a lower requirement for nitrogen fertilization than bluegrass.
Little bluestem (Schizachyrium scoparium), found in New England coastal areas, is available mixed with fine fescues,
as well as with tufted hairgrass (Deschampsia flexuosa) and Pennsylvania sedge (Carex pensylvanica).

Choosing garden furniture and decor

With the high winds and heavy rainfall in most coastal areas, any garden furniture and accessories used in a coastal
landscape has to be able to weather a storm. The more storm-sensitive things you put in your garden, more trouble
you’ll have bringing them in when the wind picks up. Stone benches will weather better than concrete an. If you prefer
wood, teak the most durable, best-weathering variety available. This wood weathers from its original honey brown to a
silver-grey. Teak furniture can be restored even after years of neglect.

Lighter items like trash cans should be well
secured or chained down. Those delicate windchimes that sound lovely in a gentle breeze could be torn apart by the
next storm. Consider giving yourself a place to be outdoors protected from wind and rain, such as an enclosed gazebo.
Storm shutters or latticework can be placed on the windows to protect them from strong winds. The sunlight magnified
through the glass will warm up interior to a pleasant temperature, even when the wind makes
it too chilly to sit outside. Take advantage of the wind with windmills and windsocks.