Patio plants | Canva
Containers: Who, What, and Why?
What kind of containers should you get? Terra cotta? Glazed clay? Plastic? Fiberstone? Wood? Metal? The answer is: yes! You can use any of these, but my observation after years of working with containers is that high-fired glazed clay is the strongest and will last the life of the garden. No surprise, it’s the most expensive. It comes in many different colors and shapes and is especially great for large shrubs or trees grown in containers. Fiberstone (a mixture of fiberglass and cement) is a nice option for a lightweight but strong, elegant container. Using terra cotta outdoors in winter is tricky as it will chip and crack. Best to reserve it for temporary crops like herbs, annuals, and some vegetables or indoor plants. Plastic can be problematic too – it stiffens over the years and cracks. Large metal troughs have become very popular recently. My experience with them is positive, although managing summer irrigation is essential, given the heat radiating from metal if it’s in direct sun.
Selection of glazed pots at a nursery | Canva
Speaking of irrigation, water supply must be considered when planning your bird-friendly container garden. At the height of summer, you may need to irrigate pots daily. Is there room for a hose? If yes, choose one that’s lightweight and strong; 25-50 feet should do. Will you be lugging water through your home? If so, converting your sink with an adaptor for a hose is an option. How many pots do you have? Is it feasible to set up a small drip system? Planning for irrigating needs now will save time and frustration later.
The Fun Stuff
Now we’re getting to the good stuff: physically creating a bird-friendly space. Birds love having different levels in the garden—places to fly to and perch, safe from the dangers of cats or other creatures. See if you can use surrounding trees or shrubs as part of your design. Street trees nearby can provide nesting and resting places for birds. You can also achieve this by planting small trees or shrubs in large pots. As they grow, birds will recognize them as places to perch, and if you’re lucky, nest. If there isn’t room for a large pot, consider adding a trellis secured to a railing as a bird perch. Clematis grown on a trellis gives nice shelter and height for birds, and its spring and summer flowers will feed pollinators. You can even use a discarded branch from a neighbor’s pruning job as a perching place—just secure the branch to a railing or pole. Fresh water is important to have for birds, and birdbaths are a great solution for that. I use a medium-sized terra cotta tray filled with water on a sturdy wooden crate. The birds visit it regularly—I just have to remember to keep it filled. Bird feeders also attract birds to your garden. There are lots to choose from including hanging, free-standing, and those with suction cups to attach to windows. Try to get one that doesn’t allow squirrels, rats, or racoons to rummage in the feeder.
Clematis trellis for height and attract pollinators | Pschoenfelder | Canva
Dark-eyed Junco in pot base bird bath | Bird Image, Canva
Plants, Plants, and More Plants
And finally, what about plants? You’ve got lot of choices. Native plants are adapted to the unique climate and soil conditions of the Pacific Northwest, so require less water and other soil amendments. Most nurseries will carry a selection of native plants, as well as other options. The best container gardens have a mix of annuals, perennials, shrubs and trees.
These complete their life cycle in one year and will generally turn to mush over the winter. But they deliver nonstop seasonal blooms that grow well in containers and attract pollinators.
These will come back year after year and can grow quite happily in containers. Flowering time is more limited than annuals, but using perennials goes a long way to filling out your containers.
I encourage you to use a tree in your container scheme. The size and impact of a tree can’t be beaten. Use a large pot, at least 20” wide and deep. The main challenge is ensuring you don’t forget about watering. Doing so stunts a tree’s growth and makes it susceptible to pests and diseases.
But How Do I Make It Look Nice?
‘Right plant, right place’ is my design philosophy. It’s important to know what conditions the plant needs before you place it. For example, no matter how much you want an overflowing container of riotous petunias, if you don’t have a sunny spot, no amount of care is going to help. One great thing about containers is that they can be moved. Use a hand truck for the big ones. Want to grow those petunias? Move the pot to the sunniest spot on your balcony. Moving pots in and out of the sun is a great advantage, allowing you to change your design seasonally. Another fun design challenge is container placement. I’ve found that grouping containers together is visually pleasing. Sometimes a solitary container can look lonely and slightly out of place.
Questions I ask myself:
How do my containers relate to the space? Can you move easily around them? Are they easy to access for watering and cleaning?
Group pots in odd numbers to give a natural look and feel. I’ve seen lovely groupings in the same color family as well as mismatched—it’s a personal choice.
Caring for Your Garden
You’re all planted up, and now you’re ready to care for your plants, in turn caring for wild habitat.
- Watering is your number one task. How much do you water? Enough to saturate the soil—you should see water draining from the bottom. Less watering is necessary in winter and early spring, unless containers are placed under an eave that doesn’t allow rainwater to reach them. During May, I’ll spot water as necessary, and in June, I definitely increase my watering, guided by the weather to help guide my watering. As it warms up, plants start growing and their roots begin to fill pots. By July and August, I could be watering some pots daily, depending on placement—more sun, more water; less sun, less water. By September and October, the weather is cooler, and I can start to ease off on watering.
- Feeding is essential when growing in containers. Every square inch counts in pots, and making sure your plants are healthy is worth the effort. Use a good quality potting soil when planting (Cedar Grove potting soil or E.B. Stone potting) and throw in some dry organic all-purpose fertilizer to give it a good start. By mid to late June, start supplemental feeding with a liquid fertilizer—Miracle-Gro works well, or other comparable mixes. Liquid fertilizer provides immediate nutrients to plants, whereas dry fertilizer takes time to break down and release nutrients. I recommend avoiding bead-type fertilizer like Osmocote. It leaves tiny plastic waste in the garden.
- Cleaning and pruning are the other important tasks. Deadhead and clip back in summer for maximum blooms and neatness. Prune to keep pathways and sitting areas clear of branches. Every 3-5 years your shrubs and trees need a good root prune, ideally in February or March when they are dormant*. To do that, remove a plant from its pot, place on a tarp and start shaving off the roots. You can remove quite a bit and then replant it back in its pot. This helps keep the plant vigorous and prevents the roots from filling out the pot completely.
*Be sure to check for bird nests before pruning. Anna’s Hummingbirds start nesting as early as February.
Waiting and Watching
After all your effort and planning, now you can sit back on your favorite patio chair, pour a nice cup of coffee or tea, and take in the sights and sounds, always keeping a watchful eye for the birds that are bound to visit your little piece of heaven.
House Finch on balcony railing | Dohoax | Canva
Jose’s Top Picks for Container Gardening:
For Height and Structure
Japanese maples (Acer palmatum) are ideal for containers and provide shelter and height. I prefer to grow upright ones as the weeping varieties tend to take up a lot of real estate as they grow. Grow them in sun or part shade.
Try Cypress ‘Wilma Goldcrest’ for a nice, neat evergreen shrub. Its conical shape makes it easy to fit in, and bright green foliage brings a blast of color to our grey winter days.
Best for Bird Habitat
Arbutus unedo, the strawberry tree, love sun and forms a large, structured shrub that can handle dry conditions.
Ceanothus species (California wild lilac) can also tolerate dry conditions and are covered with intense blue blooms that bees love in spring.
Sarcococca varieties, known as the winter box or sweet box. White fragrant flowers in February will draw you outside, and thick foliage gives birds a place to rest.
Camellia sasanqua is an exceptional evergreen shrub for shade, happily growing in a container. They form small trees and grow according to pot size. That’s why it’s good to use large pots for shrubs or trees, so they can reach their full potential. Underplanting with annuals or perennials will give you variety and interest, as well as giving a place for birds to nestle, roost and search for food. Ask your nursery staff for best selections.
More on container gardening!
Jose Gonzales hosted a Nature of Your Neighborhood webinar with Seattle Audubon and Capitol Hill EcoDistrict in 2021.
Watch the recording and learn more!
About Jose Gonzales
Jose Gonzales (he/him) has been a garden professional for over 20 years. Growing up in the PNW, Jose has learned to appreciate our unique climate and how to care for our natural environment through plants and gardening. He worked at City People’s Garden Store for 20 years, as well as being one of the owners from 2017-2020. As a gardener, Jose’s passion for plants always shines through. He helps people design and maintain their garden areas, install above-ground drip irrigation, and solve all kinds of plant issues. He also finds great joy and satisfaction as the leader of the popular jazz trio, The Jose ‘Juicy’ Gonzales Trio.
Other articles in this issue of Earthcare Northwest
Take the Backyard Habitat Quiz
How does your outdoor space measure up? Have you minimized threats to birds? Are you offering food, water, and shelter options? Discover some obvious and subtle ways you can create a wildlife haven in your own backyard.
Tim-ber? … Not So Fast: The Important Role of Dead and Dying Trees
Trees are essential for birds, even when the tree is dead or dying. We hear from Stuart Niven, a professional arborist, about how snags and woody debris can remain in your yard safely, and provide excellent habitat and food resources for birds.
How can we improve access and connectivity for people and wildlife? Seattle Audubon, the Capitol Hill EcoDistrict, and the Seattle Bird Conservation Partnership are finalizing a guide to improving habitat values and human access to green space in urban Seattle.