Hydrangeas: Beautiful and easy to maintain plants for the coastal garden

Gardening near the ocean has its challenges, but fortunately there are many varieties of hydrangea that perform well in the coastal environment. One of the biggest issues for hydrangeas are hot, dry summers, but this is rarely an issue on the Northern Oregon Coast. Unlike in the Willamette Valley, coastal hydrangeas often appreciate being sited in full sun, where, with adequate water and composted soil, they will bloom profusely.

The mophead hydrangea (H. macrophylla) is considered the modern classic hydrangea with its bold, green foliage and even bolder blooms. These hydrangeas are found in hues of pink, purple, blue, and white, but most will change color over time due to soil pH. Even the boldest pink or blue mopheads can eventually fade to a soft purple due to our acidic Pacific Northwest soils. Maintaining or changing the flower color is a matter of two things; Firstly, being certain that you have a variety that will respond to the attempt, and secondly, changing the soil pH through the use of lime (to lessen acidity for more pink hues) or elemental sulfur (to increase the acidity for more true blue hues). In both cases, changing soil acidity takes time and is not permanent, so you must be patient and persistent.

Love hydrangeas but changing soil’s pH isn’t up your alley? Oakleaf Hydrangeas (H. quercifolia) are another beautiful addition to the coastal garden. Generally white-flowered, Oakleaf Hydrangeas boast remarkable fall colors from gold to red to purple. The colorful leaves remain looking lovely and provide interest well into the colder months. On the Oregon Coast, plant Oakleaf Hydrangeas in full sun and add compost to help retain moisture.

Oakleaf

Fall color, interesting foliage

If you’re a fan of the unusual, there are plenty of new and exciting hydrangea varieties popping up every year. ‘Wedding Gown’ is a stunning white lacecap with double blooming flowers that look like a wedding bouquet in and of themselves. ‘Miss Saori’ is another double-bloomer with unique pink and white variegated petals that contrast beautifully with its dark foliage.

‘Wedding Gown’

Each flower it’s own bridal bouquet

‘Miss Saori’

Chelsea flower show medalist—amazing!

Small garden? The Cityline Series boasts a number of dwarf cultivars including ‘Pia’, ‘Vienna’, and ‘Rio’. These shrubs should stay around 3’ x 3’ and remain dense, so they don’t require the pruning that some other varieties do.

Speaking of pruning, beginning and experienced gardeners alike can make mistakes when pruning hydrangeas. Depending on variety, hydrangeas bloom on different ages of wood, referred to as “new” or “old” wood. This simply means that the flower buds are found on either last year’s stems (old wood), or on this years stems (new wood). This means that if you significantly cut back a hydrangea that blooms on old wood, like H. macrophylla or H. quercifolia, you may be inadvertently cutting of many of the dormant flower buds, sacrificing the coming bloom. The simplest approach? Cut off spent flower stems only as far back as the first set of leaves. This will guarantee that immature flower buds remain. If you find that your hydrangea is getting too large for its space and needs to be re-shaped, go ahead and cut it back by up to one-third in the fall. You will likely sacrifice the blooms for the coming year on some varieties, but the plant will be better for it in the long run.

Cityline ‘Vienna’

Check out cityline series for more compact shrubs

Cityline ‘Mars’

Compact and “Otherwordly”

If you think you’re prone to worrying about pruning, consider the ‘Endless Summer’ varieties, which bloom on both new AND old wood, or choose a dwarf variety that won’t ever require significant pruning.

Sandy Planting

A colorful border only one block in from the Pacific Ocean on Breakers Blvd. in Neskowin, OR. We did import some topsoil and this garden also has drip irrigation. Plants featured include: Sedum ‘Autumn Joy’, Mexican Feather Grass (Nasella tenuissima), Gaura ‘Whirling Butterflies’, Salvia ‘Cardadonna’, Coreopsis ‘Moonbeam’, Halimium species, Lobelia tupa, Purple Smoketree ‘Grace’, Alyssum (from seed), Cardoon, Achillea ‘Moonshine’.

Kinnickinnick - Arctostaphylos uva-ursi It's native so why not? True, but if you plant it in an area that get composted, watered or mulched it gets easily diseased. Often it will come out of winter with mostly brown foliage that must be pruned off. However if you have dry, sandy, full sun location it's an excellent choice.

Evergreen Huckleberry - Vaccinium ovatum One of my very favorite plants. Native, evergreen, and edible, requires very little maintenance after establishment.

Shorepine - Pinus contorta var. contorta Our native shorepine does best when planted in Nov-Jan and not watered in summer.

Pacific Wax Myrtle - Myrica californica My go-to plant for a screening hedge. Evergreen, native, drought tolerant.

Escallonia var.'s Try 'Red Elf' or 'Compacta' for dwarfer versions of it's very large parent.

Grevilleas 'Marshall Olbricht', 'Canberra Gem', & others These beauties prefer poor soil or sandy as they are adverse to phosphorous. A hot site with protection from wind for the larger varieties is best. Be sure to choose a hardy variety as many are not. Excellent hummingbird nectar source in early winter.

Grevillea ‘Canberra Gem’, Tulip ‘Peppermint Stick, amidst fern-like silver foliage of Achillea ‘Moonshine’

Guitar Plant Lomatia tinctoria Another unique addition from the Protea family that abhors phosphorous and so keep compost and fertilizer away. Thrives in sand. Native to Tasmania.

Leptospernum 'Squiggly'

Brachyglottis 'Crispa'

Sedum 'Cape Blanco' & others

Manzanita

Madrone

Ceanothus varieties

Coyote Bush - Baccharis pilularis

Seawatch - Angelica lucida

Halimiums and Cistus

Salvias

Rosemary & Lavender

Thyme groundcovers - Thymus pseudolanginosus and others

Penstemons

Beach Lupine Collect from seed in mid-summer. Be sure to wait until the pods are dried, brown, and beginning to open on their own. Spread in the area you hope to sow and keep your eye open for seedlings which may not germinate until fall or following spring

Plants not to plant

Some plants do well, and then they take over the garden, end up in the neighbor's yard, and won't even die in the compost pile. Many of these are on the invasive list for Oregon and should not be planted. There are many other low maintenance plants that will thrive and not spill over into our native ecosystem.

Plants I beg you not to plant, and please don’t ask me to plant them for you…I hate telling clients no.

• Mt. Bretia, Crocosmia, Lucifer's Red I know you love the blooms, so plant them in a pots and cut the flowers off an bring them in before they go to seed, but please don't plant them in your yard. The deer tend to eat most of blossoms anyhow. We call Mt. Bretia our most expensive plant as we've had clients spend more money on removing this plant than any other. It spreads by running underground and by seed. It also cannot be burned and should not go into any compost pile as it will come back.

• English Ivy Sure, you know not to plant it, but don't even plant it in a pot. I can't tell you how many times as I've climbed through a rat-infested ivy jungle I find a single cracked rotted container that was once home to a potted arrangement with a 4" start of ivy. At the end of summer, the container got dumped in the woods where it plotted revenge and 10 years later is an army ready to consume the neighborhood. Yes, even the cute variegated varietal can revert and become regular tenacious ivy.

• Lamium, Spotted Dead Nettle, Yellow Archangel, Lamiastrum galeobdolon

• Vinca, Periwinkle

• Euphorbia, Mole Plant (not all varieties are bad)

• Linaria, Toad Flax

• Mint, Chocolate Mint

• Lemonbalm

• Stipa gigantea, Giant Feather Grass

• Pampas Grass

• Phalaris arundinacea, Variegated Ribbon Grass—it's a variegated form of the super invasive Reed Canary Grass, need I say more?

• Bamboo

• Blood Grass—it reverts and turns green here anyway

• Arum Root

• Calla Lilly

• Phygelius, Cape Fuchsia

• Comfrey - It will swallow plants whole and return from the tiniest piece of easily broken root.

• Aegopodium podagraria, Variegated Bishop's Weed, Variegated Gout Weed

• Butterfly Bush

• Galium odoratum, Sweet Woodruff

Healthy Lawns by the Sea

We often get calls from frustrated homeowners who can't seem to get their lawn looking they way they want it to look. Organic lawn care is really just good gardening. The goal is make the lawn so happy and healthy that the problems go away without the need to remedy a particular issue such as weeds or pests. Grass is a nitrogen hungry little plant that needs to be fed regularly to be able to out-compete weeds and be ready for the Fourth of July picnic. Here is what we do to maintain gorgeously deep green lawns that you'll feel safe allowing your children and pets to play on.

Mowing
Mow high and often--this can be as often as every 5 days in warm spring weather. This is a very common mistake--never remove more than 1/3 of the grass blade! A longer blade length (1.5”) will feed the roots better allowing the roots to grow deeper and stronger which will provide better drought resistance in July and August. Longer grass also discourages weeds and moss. Leave clippings on lawn whenever possible, even if you don’t have a “mulching mower”. A biologically active healthy lawn will devour clippings in no time. Sometimes in the spring the clippings are too long and wet and need to be raked removed. Anytime you remove clippings from the lawn you should fertilize to replace the nutrients you removed by feeding (fertilizing).

Compost (is magic!)
Fall or early spring is a good time to apply 1/2” of light screened compost. Devil’s Lake Rock Co. has a good fine compost available. Especially important to do if your lawn is on sand. Best to do this annually, but once every other year at the minimum. You can over-seed at the same time if necessary. It will look like you've destroyed your lawn after you've down this, but just wait, you'll be shocked at the beauty in less than a month!

Summer Drought (dormancy)
If you are not irrigating your lawn regularly you can expect it to “go dormant” the end of July and August. This does not hurt the lawn as it's part of it's natural cycle just like maples losing their leaves in the fall. It does mean you have to tolerate a brown lawn for a month or two in the summer. However, if it is exceptionally hot and dry, it is a good idea to give the lawn about 1/4” of water once a week to keep the crowns alive. This is historically not necessary at the coast due to ambient moisture, however, I'm seeing the need for this more and more. It is fine and even admirable to save water by letting your lawn go dormant, but if you start to water too much after your lawn has browned you may break it’s dormancy and so will need to continue to provide consistent water or it will be wasting energy. It isn’t good for the lawn to go in and out of dormancy more than once a year. This is all complicated further when going grass in sand and I would suggest adding topsoil if that is your lot in real estate and life : )

Fertilizer

There are many good organic options these days, however, not so many are locally available.  The best locally available option we've found is available at most Ace Hardware stores:

Milorganite - Organic Lawn Fertilizer
36# per 2,500 sq. ft.
5% nitrogen, 2% phophorous, 4% iron

Slow release organic fertilizer that only works when soil temperatures are between 55 and 85 degrees. For best results, apply 3-4 times per year, but spring and fall are most important times to fertilize. If you leave your grass clippings to mulch on the lawn, don’t bother with summer fertilizing. Each time you remove clippings from the lawn you will need to replace these nutrients somehow.

Dates to fertilize:
Memorial Day (or when soil temp is 55 degrees+)
Fourth of July
Labor Day
Thanksgiving

Iron--”Moss Out” or “Ironite”
Our soils are naturally deficient in iron.  Iron will help kill moss safety. Be sure the only active ingredient in the product is iron and not another toxic substance. Available as pellets or liquid to apply through a hose-end sprayer.  I use the pellets for ease of application.  Apply in late spring or early fall when lawn is wet, but temperature are in the 60’s or 70’s.  Milorganite contains iron, but sometimes more is needed as an initial moss treatment. Also good garden bed amendment for rhodies and most plants.

Lime
Pelletized or “prilled” is easiest to apply and doesn’t make such a mess.  Lime feeds the lawn and also reduces moss.  Apply in fall and/or spring.

Overseeding
Why not reseed any bare spots from pulling out a dandelion as they appear? Mix the seed with compost and keep watered. In fall or spring you can “overseed” the entire lawn with fresh seed. I use the lawn seed from TCCA farm store in Cloverdale as it is a good mix of grasses for the coast. If you applied iron to kill the moss--wait two wks, then rake out moss and sow grass seed.  Apply 1/2” compost if you can to over the seed.

Weeds
If you have a lot of weeds its because the culture isn’t calibrated correctly for growing grass. Is is too wet or dry? What kinds of weeds do you have and what sorts of deficiencies do they indicate? If you have a lot of dandelions you need iron & lime-- try hand pulling and overseeding. Next year there will be fewer dandelions--pull a few more and keep up the regime. In a couple of seasons, you won’t have dandelions. Why not leave the clover as it feeds the grass nitrogen, stays green, and flowers. Dutch white clover is an excellent low-growing choice for blending into a lawn.

Landscape Edibles

View fullsize

Non-galvanized Steel Fencing for elk protection

Growing Edibles in your Landscape

This is something that seems like a no-brainer that everyone can get excited about. As long as you are growing plants, why not grow something you can eat? For the most part that is true, however, at the coast it's so much easier said than done for two major reasons: deer and elk.  Most of the plants that we like to eat are also deer candy. This is especially true of apple and pear trees as they are in the rose family.  Every enthusiastic new coastal gardener has quickly learned the hard way that roses impossible to grow at the coast. Deer repellents do work for most plants when applied on a weekly regime, but not for roses.  Yes, for ruminants, anything in the Rosaceae family is tasty enough to still be worth eating even when doused in "putrified egg solids", castor oil, blood meal, and sprinkled with cayenne pepper. 

When a client is serious about growing food the first step is to put up a fence or deal with individually caged beds or trees. If this is not something desirable, either for aesthetic reasons, or for HOA code, then you can still grow artichokes and most herbs.  Deer won't touch artichokes, rosemary, thyme, savory, lovage, sage, and most other oily plants. Also, not all fencing and cages are ugly. Personally, I like the look of non-galvanized steel remesh as it ages to a lovely rusty patina that disappears into the surrounding landscape. It can also be installed in a way so that the fencing panels are removal and can be lifted out for access.

View fullsize

Alpine Strawberry 'Mignonette' growing in a stone wall in the Coast Range

View fullsize

Agribon Spun-row covers from Peaceful Valley Farm Supply

Salt air and wind are two other factors that can limit the success of fruit and veggies at the beach and on coastal headlands.  Cloches, cold frames, or agricultural spun row covers are an excellent means of protection against wind, excess rain, salt spray, and also many common pests.  

Edible Plants for Landscape Setting on the Coast...

Plants were selected based disease-resistance, ease of pruning, general good behavior, tidiness and beauty.

1. Artichoke 'Green Globe' and 'Violetto'*

2. Jostaberries

3. Alpine Strawberry 'Mignonnette'

4. Rhubarb*

5. Fig

6. Evergreen Huckleberry*

7. Rubus calycinoides 'Emerald Carpet'*

8. Chives*

9. Rosemary*

10. Thyme*

11. Ornamental Grape

12. Aronia

     * - deer resistant (usually)