We’ve almost made it. Spring is nearly here, with flowers, tomato towers and long daylight hours just around the corner.
As you wait for the season’s official arrival, start preparing your garden and outdoor areas so you can make the most of the sunny, dry days to come. We talked to Erin Lau, owner of southeast Seattle landscape firm Erin Lau Design, to get her tips on steps you can take now to make your yard a place where you truly enjoy spending time once the weather warms. The conversation has been edited for length and clarity.
Q: What’s a good way to get new garden beds ready for planting?
A: One method of preparing a new planting bed for vegetables, or any sort of planting, is to sheet mulch. That’s the process of putting compost down first, and then cardboard, and then perhaps another layer of compost and organic material such as leaves or straw. Some people would put wood chips on the top layer.
You can do this to smother grass — for instance, if you want to make a new planting bed where there was grass previously. Or you can just do it to create a nice, thick, very rich and fertile new planting bed in any spot — maybe it’s already a cleared piece of dirt. And it can help smother weeds.
But you have to be very meticulous about your cardboard usage. You have to cover all the air gaps and all the gaps that let light in, because if there are any gaps, that’s where the existing weeds or grass could still come through.
Then I like to do another layer of compost, or soil even — something that’s dense to really hold the cardboard down. You don’t want to just put leaves right on top of the cardboard, because they will just fly off and the cardboard will fly off.
Q: What should people know about using compost in their garden?
A: Typically, if you are staying really on top of your garden, you compost your bed up to twice a year, fall and spring. It’s hard for most homeowners to get to it that often. It might happen once a year, it might happen every two years. But adding compost around your existing plants is a good way to add nutrients to the soil and give them that extra boost at the beginning of the growing season.
It’s a little late for this, but composting also helps protect against frost and soil depletion from rain, which is really more why you would do it in the fall. But at this time of year, it’s more about getting nutrients into the soil.
You want to get a really fertile compost. You don’t want to get just a bark, or what people refer to as beauty bark. That’s not considered a compost, that’s more a top dressing. It typically dries out the soil in an unbeneficial way, in a detrimental way.
But wood chips that you get from an arborist, that have a bit of leaf in it and a bit of twig and a bit of bark, those are good for the soil, because all those different materials break down and biodegrade and become nutrient-rich.
Q: What kind of plants work well in the Northwest — or not?
A: All greens are really easy to grow here, so all lettuce greens, brassicas, peas, root vegetables such as carrots and beets, and alliums — onions, garlic — all those are really easy. It is hard to get cauliflower and broccoli to fully form florets, and they just take up a lot of space, but if you have dedication you can get them to where you need to.
Things to not grow here are a lot of the really sun-loving plants, like eggplant — it’s very hard to get it to fruit. Also, it is hard to grow peaches and apricots, because they just need a lot more sun than we can give to allow the fruit to ripen. And then in terms of succulents — we can grow sedums, but it’s very hard for us to grow most of the succulents you see in California gardens that are really big and flashy. And then, generally, tropical plants overall are harder to grow here. I have seen people grow banana plants, but they actually have to cover them in the winter to keep them alive.
Q: What should people keep in mind when planning their landscaping?
A: You always want to start thinking through your space in terms of plant heights — are you looking for something short or medium or tall? And then from there, you can begin to whittle down the options within the shade category of the nursery or the sun category of the nursery.
I think it’s always helpful to choose an evergreen ground cover, if you’re going to use a ground cover at all, and then you can choose something that’s not evergreen for the next few layers. That can help to establish a good foundation.
And then you can think about, like, is this shady space kind of dark? Maybe you want to brighten it up with foliage that is chartreuse or variegated so it really pops, or even a gray-green. Maybe flowers will bring that pop of color. Or if it’s light enough that really dark green foliage will show up, then you can go for the dark green.
I love using Epimedium as a low-maintenance, low-water plant. Brunnera Jack Frost is really nice for brightening up an area, because it has kind of silvery green leaves. And then there are new cultivars of hellebores that have variegated leaves. With some of them, the flowers now point up — or you can get the traditional ones that have drooping flowers.
Q: What tips do you have for people looking to add hardscaping?
A: As a designer, I would say the first thing you need is a design. Because without a design, you don’t have your decisions made. Having a design means that a bunch of decisions have already been made and communicated on paper. Even a simple sketch to scale will do. Even if you’re doing it yourself, you’ll want a design, because you want to be able to know how many pavers to buy or what square footage of gravel you need.
If you’re doing it yourself, you want to make sure that you’re planning for your hardscape assuming this is a place where you want to maybe dine or lounge. You want to plan for it in a location that you know you would definitely hang out in. You don’t want it under a conifer tree. You want it as close to your house as possible. And also, if you’re seeing right now that it’s super muddy and mucky, that might not be the best spot for your hardscape location, because you’ll continue to have drainage problems, or you’ll make them worse if you put hardscape there.
So definitely now’s the time to survey your yard and see where the water’s pooling. If the water’s pooling where it’s the perfect spot for your patio, you’re going to have to consider drainage remediation to direct the water away from that location.
Q: What do you recommend for people with drainage problems?
A: It really depends on the source of the water, and its destination. If you can control the source of the water, that’s obviously the easiest thing. If it’s clearly coming from a downspout or a gutter that’s not hooked up properly, address that first. If it’s coming from your neighbor’s property or from the road — maybe you’re below the grade of the road — then there’s not much you can do to prevent it.
I would say that French drains, trench drains, and drywells and sump pumps are your best friend if you have drainage issues. You’re going to want to make sure the drainage stays away from your house, and you have to drain it to something like a rain garden that then might overflow into some other drain. It’s not always possible to hook up into the city’s side sewer because they want to reduce the potential for overload in the city’s stormwater system.
Q: What can you do with a lawn that’s a muddy mess after our rainy winter?
A: Ultimately, you’re just going to have to have patience and wait till it dries out. The key thing is to just leave it alone and not walk on it, not bother it — because that just makes it worse. If you have a lawn that’s trending toward muddy but you can still walk on it, the more you walk on it, the worse it’s going to get and the more grass is going to be trampled, and the mud’s going to come up to the surface. So leaving it alone is the best option until it dries out.
But if you’re wanting to soak up the moisture right away, like right now, then you would add some sort of organic material like wood chips or compost or leaves. And this is a good time to add compost anyway to your planting beds.
When it’s not so muddy and you can walk on it, you can dethatch and aerate it. That brings oxygen into the soil, and it kind of loosens it up.
Thatch is dead grass clippings that have collected in the lawn over time. The thatch actually does add nutrients back into the lawn, so you do want to have some thatch in your lawn at times. But it can build up to sort of a mucky layer, so the dethatching helps to remove that.
Q: What is your approach to designing lawns in the Northwest?
A: I have a philosophy of having a diverse lawn in Seattle, and not having a perfect golf-course aesthetic. Because once you start to go down the path of having a perfect manicured lawn, then you’re dealing with a very high-maintenance lawn.
So if you’re open to having a diversity of plants in your lawn — which means it’s not just grass, maybe there’s some clover, maybe there’s some yarrow, maybe there’s some little daisies in it — then it becomes a much lower-maintenance part of your yard, and you potentially have to water it less in the summer. Or you can even let it go dormant.
If you’re open to that type of lawn, I would suggest getting a seed mix that has a microclover in it. The microclover acts as a way to fix nitrogen into the soil, because clover has nitrogen, and that’s what a lot of fertilizer is — nitrogen. As it decomposes, it re-adds nitrogen into the soil, and it also can keep your grass looking greener throughout the year than if you didn’t have the microclover.
So I’m a big proponent of diverse lawns, and I’m also a big proponent of the idea that in a place like the Pacific Northwest, if you’re OK with a high-diversity lawn that goes dormant in the summer — meaning it turns brown — then lawns can be low-maintenance here. But if you want to go the opposite way, then you’re paying a lot more and you’re maintaining it a lot more.
Q: What kind of pruning should people be doing right now?
A: You want to make sure that you have done all the pruning that you need to, of either perennials or trees or shrubs. So if it’s perennials that you left throughout the winter that you never cut back, something that maybe still has a flower stalk on it and you let it go brown, you want to cut all those right now, because you want to make sure that the plant has room and also is clean enough to shoot up its new fresh growth for this coming year.
But you want to really be careful that you’re not pruning off the buds that have been formed, because those will become flowers. If it’s clearly dead stuff that’s brown, that’s fine to prune, but you just want to be careful about pruning off buds that have formed. If you do, you won’t have very many flowers in summer because you’ve cut them off prematurely.
Q: If you’re going to work with a designer to landscape an area, what homework should you do before you talk to them?
A: It’s great if you have a collection of inspiration images, whether it’s on Pinterest or Houzz or from magazine clippings — but especially inspiration images that are suited to this climate. And just writing down a list of your goals.
It’s less about particular things, such as “I want a potted-plant section,” or “I want a firepit.” It’s more about: How do you want to use the space? What is the function of the space? And then the function informs how we create the space, and formulate the space, and create the flow of the space.