Coastal gardening presents some big challenges. There is constant strong wind, sandy soil that doesn’t hold water well and is lean on nutrients, and the salt! Oh, the salt.
Of course, it has its benefits too. Nowhere else do you get such a sense of motion in the landscape, between the beauty of the waves and movement of the foliage in the wind. And if you can incorporate the ocean view into your garden design, working with your layout and plantings to make the view feel like it’s part of your garden rather than a far-off bit of scenery – then your landscaped areas can take on a sense of openness and grandeur that other gardens can’t touch.
Over the course of the month, in between other posts, I’m going to be talking about some of the plants that thrive in windy seacoast conditions, design tips to make the most of your space, and books that you’ll find helpful if you’re gardening on the coast.
To start, I want to talk about a few coastal gardening tips that might go counter to what you’ve learned about gardening elsewhere.
Design with mostly lower-growing plants
While in a regular garden it’s great to have varying heights for visual balance, in a coastal garden tree canopies and large shrubs tend to act as sails, which catch the wind and whip the poor plant around. I’ve seen 3” diameter tree trunks simply snap on a very windy day.
Obviously there are some places where you’ll want to create privacy or screening, or where you’ll need the visual weight of a tree or tall shrub. But on the whole, the taller the plant, the more grief you’ll have getting it established and keeping it healthy. Work with your surroundings, and when in doubt select a lower-growing plant.
Plant in masses
On a similar note, planting masses of the same plant and allowing them to grow together in a happy grouping has two benefits.
First, plants that are the same height tend to get less wind and salt burn because the wind just goes up and over the whole group. The wind seems to catch more on plantings of various heights, which means each plant tends to sustain more damage in highly mixed plantings.
The second reason is that plants growing together in a mass creates a visual echo of the ocean waves. That creates the subconscious sense that your garden fits with the surroundings.
Obviously, you’ll want to allow enough room for each plant to spread to mature size when you plant. Whenever possible, plan for their edges to just touch when they are mature. The constant airflow in a coastal garden helps prevent the fungal disease that can happen in normal gardens if plants are massed closely.
Buy bigger plants to start
While in most gardens, a one-gallon size pot is perfectly sufficient to make sure your plant will survive the shock of transplant, in really tough conditions, it can be better to start with plants in larger pots, particularly for woody shrubs.
Because the wind is constantly causing them to lose moisture, the larger the pot, the more root mass and foliage your plants will have to help them replace lost moisture and nutrients.
Just stake any plants that are in danger of blowing over (be sure to allow them to sway with the wind to encourage their trunks to develop “muscle”!), and select plants that look hardened-off – don’t pick the lushest, fluffiest plants at the nursery, that have been over-fertilized and babied.
Use overhead watering periodically
While most shrubs and perennials don’t appreciate their foliage being sprayed down regularly (I recommend drip irrigation for that reason), plants living in salty conditions actually benefit from being washed periodically.
If you’re on the front lines where your plants are constantly buffeted by salty wind, then washing your plants and thoroughly wetting your soil once a month can help prevent foliage burning from salt, and can rinse salt buildup from the soil.
This is the only time when I’d even consider using sprinkler heads or overhead watering for landscape plants, because usually plants develop fungal diseases or just fail to thrive when their foliage is constantly wet. But right on the ocean, the water left on the foliage dries up very quickly, and the health benefits of rinsing the salt off the leaves seems to outweigh the threat of fungus that comes from irrigating with sprinklers.
Lastly, treat your plants with extra care
You may have heard that you can plant things in fall, let them get established through winter, and then not water during the growing season. That works for some plants, in some gardens. That will probably not work for your garden – sorry to be the bearer of bad news, here! Coastal gardens put their plants through waaaay too much stress and moisture loss to expect them to look great without care.
When starting new planting beds, amend the top 10” of the soil with plenty of compost and manure to help the sandy soil hold moisture and nutrients. Use a thick layer of wood chip mulch after planting to hold moisture in.
Make sure you are watering regularly enough, and get out there and check the soil around your plants to be sure they are getting good coverage. Water is critical to success in a windy coastal garden.
Use organic fertilizers in your garden beds that will release slowly. Synthetic fertilizers like Miracle-Gro will wash straight through your sandy soil, providing a quick jolt of too much fertilizer, then stressing your plants through not enough. Organics tend to release at a more steady rate.
If you’re gardening on the coast, I hope you found these tips helpful! Want to read more? Check out these articles: