Successful Gardening in a Coastal Environment
August 18, 2016 12:00 am
We often get asked what plants do well in a coastal situation. Having just returned from a week on the southern Oregon coast, I had the time and opportunity to see for myself, and am happy to share some good options. Here in western Oregon we have what is usually referred to as a Mediterranean climate, meaning mild winters and warm, dry summers. As any gardener here knows, the possibilities to grow interesting, unique, and fabulous plants here are nearly endless. On the coast, there are three additional important factors to keep in mind, that might make coastal gardening challenging. To my mind, these factors renders coastal conditions even truer Mediterranean than our more forgiving inland version.
The three factors of the coastal challenge:High and frequent winds
- High and frequent winds
- Often sandy, fast-draining soils
- Salt – both in the air, and often in the groundwater
Because of the less extreme temperature fluctuations near large bodies of water, you can also often push your boundaries a little more than you can farther inland, which is always fun! 🙂 As a result of this, you will, for example, see Phormiums of a size you hardly ever see in Portland. And, I bet coastal gardeners have never even heard of a “Phormium winter”, like we experience here, from time to time, when all our lovingly tended New Zealand flax dies.
This Phormium is in bloom, which is another feature we don’t often see in Portland. And, it is of an entirely different proportion than their inland brothers and sisters.
The windy coastal conditions creates a need for screening. Here, the evergreen density of Escallonia is put to work to create shelter from the howling gales and breezy barrages so often experienced on seaside properties.
Climbing roses, Bergenia, Agapanthus, Sedums, Zauschneria, Cistus and ornamental grasses accompany the dark foliage of the ornamental cherries anchoring this coastal cottage garden.
There is a decidedly California flair over this seaside, streetside garden – Leucadendron, Parahebe perfoliata, Phormium, ornamental grasses, Ilex, etc. The large Rhododendrons in the background give a nod to a more traditional Oregon plant palette.
Hebes is a great, popular alternative – here seen with a wind whipped Pine. The general rule of thumb when it comes to Hebe varieties is that the smaller the leaf, the hardier they are.
And, since you can push the envelope in milder coastal climates, you can get away with using the showier, larger-leaved varieties. Hebes are evergreen and bloom for a long time, with white, pink, or purple blossoms.
Erigeron is a tough, pretty, mounding plant that blooms for a long time with small, daisy-like flowers. Here placed in front of a row of Agapanthus.
Succulents are a fantastic option! Agaves, Sedum, and Sempervivum all perform fantastically. Here is the hot pink Delosperma planted with pink Seathrift (Armeria) that has mostly finished blooming.
These incredibly exposed wild succulents were growing on a vertical rock face out in the ocean. I snapped the photo during low tide. I wouldn’t have been able to go near it otherwise. I’m guessing they are a mix of some kind of Sedums and Sempervivums.
Eucalyptus offers a perfect, evergreen tree for fast-draining soils. The leaves might turn red when heat stressed.
Conifers often do well on the coast. Junipers, Pines and Cypresses are common. Here is the free-form silhouette of a conifer paired with a more formally clipped broadleaf evergreen shrub, and the sky blue rounds of the Agapanthus.
These exposed Pines put up a constant battle against the Western winds of the Pacific Ocean. As you can see, wind is a major factor in seaside gardens. Use the lee side of your house to your advantage, to cultivate your less sturdy plants.
The dramatic foliage of an Echium is a great attribute to any garden, but be sure to put it in a less windy spot, to ensure its towering flowers do not collapse.
Rosemary does phenomenally well on the coast. After all, it is a Mediterranean plant in a very Mediterranean climate.
Hydrangeas do great on the coast. This one is on the lee side of a building with an eastern exposure, bu. Normally this would be a great spot for a Hydrangea, but this one is looking rather sad. Hydrangeas are thirsty plants, and love ample moisture. If you plant them in fast draining soils, you need to provide them enough water to look their best. You can see from the crispy mopheads that it’s not entirely happy. 🙁
You can tell that these photos are from the southern Oregon coast, as some of the plants are decidedly Californian in stature. Here are a couple of mature Cordyline australis – the likes of which you may not readily see on the northern coast. Yuccas might be a good alternative in those colder areas.
Roses, Crocosmias, Agastache, Ceanothus, Achillea, Salal, Lavender, Santolina, Cannas, Poppies, … the list of tough, excellent, salt-tolerant plants is a long one. You can find an excellent list here. Hopefully this post will get you some ideas of what might work where you are. And, we are of course always available to answer more questions. Just stop by our Showroom on 5645 SW Scholls Ferry Road in Portland, OR.
A little past their prime, but still lovely, tough-as-nails California poppies adorn the seaside landscape. It doesn’t get much better than that!