Fabulous winter containers? You CAN grow that!

Hard to believe, but Seattle does have four seasons, but our grey and cold season lasts from October to March.  Sure, we have wonderful winter-fragrant shrubs and winter-busting early colorful bulbs, but our long-lasting damp just makes most foliage turn to mush.

Which is all the more reason to create a fabulous winter container to enjoy as you dash from car to doorstep.  This container cleverly conceals an unsightly drainpipe in the McVay Courtyard at the Center for Urban Horticulture, and just glows in the late afternoon winter sun.

Fashion advertisement for winter containers[Pin for Later]

Contained choices

For a big impact, choose the largest container you can afford.  The one pictured is just over three feet tall and makes a sophisticated statement.  You can see that this simple green container is planted up with a refined color palette of red, silver, and green plants.  The same effect can be achieved with glamorous red or sophisticated black containers.  Alternatives for the budget-conscious include containers with a smaller stature, either in glazed pottery or the wallet-flattering Fiber-Cement.  Work with a Container Designer to have access to the best pricing.

It’s always about the plants

I couldn’t have done any better than designer JP Sauerlender, who combined these simple winter-hardy plants and pushed the edge with the silvery Astelia.  The foundation of this container is the silver-leaved Brachyglottis, a drought-tolerant shrub with yellow flowers in summer.    Slow growing and perfect for containers, it retains its strong structure throughout the winter.

Sophisticated Winter Plants for Containers | #eTilthThe container is also anchored with a dwarf hemlock.  Since the one actually in this container,  Tsuga heterophyllus ‘Iron Springs’, will end up being a 12′ tree, I recommend instead Tsuga canadensis ‘Jervis’ which will top out at 3-5 feet and won’t outgrow the container.

The beautiful and elegant Astelia ‘Silver Shadow’ is a new plant for me.  All the books say it is a zone 8b plant, which means we’re pushing the edge of cold-tolerance here in Seattle.  However, because it’s in a container where we can control the amount of water it gets (i.e. fast drainage), and because it is in a protected courtyard, I think it will sail through our prolonged freeze.

Designer’s Trick

Shh.  This trick is an old, but good one.  Simply go down to your local floristry supply store and buy a bundle of red-twig dogwood stems (or cut your own from your rain-garden, right?), trim to size, and just shove them straight into your container!

In summary, with just a few simple plants and an elegant pot, you can dress up any front-door with a sophisticated design to brighten your winter.

[This post is inspired by the garden bloggers’ theme #YouCanGrowThat and #YCGT – look for it everywhere on Twitter,  Instagram and Facebook.]






Tiger Eyed Look

Which came first, the container or the plant?

Sometimes, when I am asked to design a container, we start with the homeowner’s existing containers and build from there.  Other times, the owner fell in love with an amazing plant and just wants to enjoy it all season before deciding where to plant it.  Holding a plant in a container is a great way to know how it behaves throughout the year.  But sometimes, it’s hard to make it look its best for the season.

Here, a homeowner on a garden tour wanted to make this Sumac (Rhus typhina ‘Tiger Eyes’) really shine.  This isn’t my design, but I wanted to share with you why it works, so you can do this too.

Lime green sumac in a blue container with pelargonium and other summer annuals

Complementary Colors

Do you remember your color wheel?  If we started creating a planting combination taking our cues from the blue pot, we could have planted it up with orange annuals, and grasses like my favorite orange Carex testacea (the dotted line shows complementary colors).  However, that’s a little bit flat and boring.

Color Wheel showing Complementary and Split-Complementary colors
Instead, we can use a Split Complementary combination technique to make the limey-golden leaves of the Sumac really shine.  By adding annuals with orange, blue, and purple accents we make the container really pop!

Fashion Magazine style plant container combo

Get the Look

[Pin for Later] The key to this combination really is the blue container.  Make sure you choose a wide container so you have room for all of those plants!  One with a slight taper will make it easy to re-pot when you decide to plant the sumac in the ground.  You can splurge by choosing a fancy glazing, or an interesting texture, but there is so much interesting plant material that really, anything will do.

Then choose your feature plant.  The golden Sumac shown is a great choice, but if you choose to plant it out in your garden, it is known to sucker … that is, you will have runners and new Sumac plants all over.  Which is great, you’ll be able to give some to your friends!  But if you don’t want to risk it, there are a lot of nice small conifers to choose.  I recommend Chamaecyparis lawsoniana ‘Empire’ with its conical form and golden color.  Karen Chapman has a great description of other small conifers that are great in containers.

Next, accessorize!  Keeping with the Fine Foliage theme, add annuals and perennials with supporting leaf habit, for a long-season of interest.  Here, Pelargonium hortorum tricolor, with its triple-variegation, brings in the third color – orange!  The supporting cast includes long-lasting annuals like Bacopa ‘Gulliver’s Blue’, Lysimachia ‘Persian Carpet’ and the Blue Pimpernel, Anagallis monellii.   But don’t be paralyzed if you can’t find the ones listed here.  Make these easy substitutions:

  • Can’t find the three-colored Pelargonium?  Look for the alternative Pelargonium ‘Vancouver Centennial’ with its wavy edges.
  • No blue Pimpernel?  Use trailing Lobelia instead!
  • No creeping jenny ‘Persian Carpet’?  Try Lysimachia ‘Midnight Sun’ or even the lime-green Ipomoea ‘Margarita’ to get a golden trailing plant.
  • No blue Bacopa? Look for a purple aster, the Swan-River Daisy Brachyscome, or rely on a purple Petunia!
  • Add some Violas to extend the season or pop in some bright Nasturtiums

Whatever you do, have fun and enjoy your plants.




Of Cabbages and Kings

The time has come to talk of many things …

I’ve spent over a year away from the blog, exploring growing flowers for market, permaculture, garden design, and have settled on my love of photography and container design.  I’ve enjoyed posting many of my images on facebook and instagram and intend on continuing there, but sometimes the short-form is not sufficient to teach and share.  So I am returning to a newly restructured website, and am launching a new series of posts called:

Garden Recipes

Here I will post an image of great garden or container designs and take them apart so you can recreate the looks too.  However, having a shopping list never works.  Where’s the fun in creating something EXACTLY the same?  Inevitably, the plants you’re looking for aren’t at the garden center that week, or maybe a key design element calls for a purple pot and you only have an orange one.

I want to add something new – I want to teach you how to analyze designs yourself so you can start to see what you like, what you hate, and how to make substitutions on-the-fly.

So, let’s start with something simple:

A closeup image of a winter cabbage with pale pink in the center, fading through white and cream, to the laced green edges.


I have a love-hate relationship with cabbages and kales (they are all in the same genus Brassica oleracea, and the differences between brussels-sprouts and broccoli, or kale and kohlrabi are just developmental forms.)  I do crave their hearty, bitter flavour in the winter, and their refreshing crunch in sourkrauts and coleslaws, but gosh, they take up a lot of space in my garden.

However, they scoff at frost and laugh at snow, putting the rest of my mushy plants to shame.  Being ideal for our short, but damp and cold winters, I just buy them fully-grown from my garden center and enjoy all of the different colors and textures.  Because of their hardiness and all of their variation, they are perfect for using in winter containers.

Aqua container with perennials and an aqua and white cabbageThis was taken on a very cold day; you can see how sad and limp the lower leaves of the cabbage actually look, but they bounced back immediately and were perky again as the day warmed up.

Containers are perfect for front doors.

Because I rush from house to car and back inside again, and usually in the dark or rain, I don’t linger much outside.  I make the quickest daily trip to the chicken coop, and once a week I dash into the greenhouse to water.  My biggest gardening joy in the winter are the containers by the front door.  It makes the most sense to plant these up after Halloween (in that little gap between mischievous monsters and the relentless holiday rush).

Why this works:

It’s sort of silly to mimic a fashion magazine, but you can print and take this recipe to the garden center.  This design is driven by the aqua color of the container; I’ll show you some variation later in the post.  [Pin for later: http://bit.ly/2jVSJmt]

Winter Cabbage Container Shopping List | #eTilth

THE FOUNDATION LAYER (1) – This combination is anchored by Chamaecyparis lawsoniana ‘Snow White’.  There are several good Lawson’s Cypress to choose, but ‘Snow White’ has this lovely blue color in winter and will get white-tipped new growth in spring.  Another option would be Chamaecyparis ‘Treasure Island’ which has golden-tipped new growth.  If you chose that conifer, you might plan on using different, golden-variegated perennials (2) in your combination. Why is this such a great choice?  It is slow growing and will be a long-lasting anchor plant for several seasons in this container.  Because it doesn’t like to be water-logged, use any good, fresh potting soil in your container and make sure your automatic (or teenager-chore) watering system is regular.  It will reach 5-6 feet and about 2 feet around in about 10 years, so plan on using it in larger containers over the years, or plan its final location in the garden now.

A SHOWY TOP (2) – Always pair your anchor plants with perennials to draw the eye where you want it to go.  Here in Seattle, we don’t get the harsh winter cold of the Midwest, so we have a lot of options to work with.  This winter-hardy Euphorbia ‘Silver Swan’ has great structure and the creamy variegation is one that we’ll play off in the rest of the container.  This plant works especially well in this pot because it also contrasts nicely with the darker conifer.  It takes the same watering and partial- to full-sun that the conifer needs.  (Take care in the spring if you cut it back, because the milky sap that wells out of cut ends can harm your skin.)

If you can’t find this exact euphorbia, look for a white-edged variegated boxwood, a variegated skimmia, or another small-leaved shrub.  The variegated Daphne transatlantica ‘Summer Ice’ would be perfect for a pot in a protected place because you’ld also get the fantastic lemony scent.   Basically, you want something tough and evergreen to stand up to the frosts and not turn to mush, but you also want the creamy edging on the leaf to brighten the container.

SOME BRIGHT LIPSTICK (3) – Although it’s small and hard to see in this image, a hardy Cyclamen hederifolium is starting to emerge.  The veined tracery in the leaves also echos the variegation of the other plants, and the dark red flowers are a good power-punch of color.   Often when you put containers all together in one season, not all of the plants you want are available.  One solution is to leave space; tuck in a few small, empty, 4-inch containers in your arrangement.  When you finally buy your blooming cyclamen, you can just pop them in!  If you can’t find Cyclamen, the dark purple, small-faced pansies will always work, but keep to one color scheme and don’t buy yellow AND white AND purple AND striped.  Any good contrasting color will work, just keep it simple.

COMFORTABLE SHOES (4)  – A few trailing plants always make a container look well-dressed.  Here a simple Vinca major vine trails over the edge.  You could have also used a white-variegated one, but too much variegation can look busy, so here the solid form was used.  Whatever you do, in this container, don’t choose one with golden edges!  This plant can be used in your container all year; just trim up the ends and you’re good to go!

ADD SOME JEWELRY (5) – Our focal point – this creamy cabbage just makes everything pop.  The frilly edges are a lovely contrast to the smooth leaves of the perennials and the soft texture of the conifer.  Had we chosen the cabbage at the beginning of this post, the pink centers would clash with the dark red berries on the next plant.  It will start to elongate in spring, so feed it to the chickens when you’re ready to disassemble your container.  Although I doubt you’ll have trouble finding the cabbage, you could have also used a lovely white hellebore.  Helleborus niger ‘Josef Lemper’ has upwards-facing white flowers (that might sag down with a prolonged freeze), H. ‘Ivory Prince’ is a stalwart, and even H. ‘Snow Fever’ would be fun, with its speckled variegation.

AND PULL IT TOGETHER (6) – Finally, we end with this versatile, easy-to-find filler, Gaultheria procumbens, also known as Wintergreen.  This heather-relative looks sharp all winter, and the edible red berries (which I think taste nasty), provide another jewel-like layer that lasts throughout the season.  In spring, it’s easy to pop them out and put into a shady part of your garden, and grow on to reuse again next year.  Alternatively, you could go for a simple heather, like Erica carnea ‘Porter’s Red’ (which is really a dark pink). If you didn’t use either of these, a shocking, red-toned Heuchera ‘Fire Chief’ or H. ‘Fire Alarm’ would be amazing.

Add more vegetables!

One simple change to make for a different look is to add other winter-hardy vegetables.  Consider adding Swiss Chard (which is in the beet-family) like this red-leaved one or the red-stemmed (‘Ruby Red’).  Alternatively, this variegated thyme adds additional variegation, which could also complement the white-ribbed chard ‘Fordhook Giant’.   Here the winter vegetables are paired with the red cyclamen.  I’m not sure what the variegated shrub in back is, but you could use a small Ilex crenata variegata, a Daphne burkwoodii, or Osmanthus heterophyllus ‘Goshiki’, Euonymus fortunii ‘Emerald Gaiety’, all of which are small shrubs suitable for many seasons in containers.

small aqua container with cyclamen, chard and cabbage
Change the container

Another simple change is to use a different planter, and choose perennials to match.  Here, the perennial stealing the show is Euphorbia x martinii ‘Red Martin’:

Red container containing same white variegated cabbage with different accents.

Whatever you choose, make sure you pack your containers full of plants to get maximum impact right away.  Your plants won’t grow much over the winter, so don’t expect things to fill in.  Sad holes should be plugged up with pansies, but make sure you keep to your color scheme, or you may end up with cabbage soup.











Spring Reminders for Pacific Northwest Gardens

It’s sunny.  No, it’s hailing; never mind.  Actually, it’s beautiful outside, gotta run out and start some seeds.  Crud, it’s raining again. OK, I’ll work on my Spring ToDo list.  Which means adding three things to the bottom of the list as I cross of each one from the top.    I totally didn’t want this post to get away from me, but honestly, it’s like, number 53 on a list three pages long, so I’ll be brief:

Pin for Later: http://pin.it/ZfcQ5id

Early Spring in the Ornamental Garden | #eTilth

Top three things to do in the Pacific Northwest Spring Garden

  1.  Prune.

Seriously, what can be more satisfying than whacking at things?  You get big dramatic changes, and let in a lot of light, lifting your mood.

My first advice is to sharpen your tools.  I have an old pair of loppers that I keep wickedly sharp (and never let my husband use), as well as a couple of sizes of Felco hand-pruners.  I probably don’t need that many, but it’s really nice to leave one in the car for making some semi-hardwood cuttings (I mean, sidewalk pruning.)  I actually keep a file with my hand-pruners and sharpen them before every use.  The only time I bother to disinfect my pruners with 10% bleach is before and after I’m cutting something obviously diseased.

My second advice is to take a pruning class.  I’ve totally loved each of the University of Washington Botanic Garden Pro-Hort Master Pruning classes at the Center for Urban Horticulture [PDF], co-hosted by Plant Amnesty.  You can watch these free videos on YouTube to get specific pruning information on a variety of trees and shrubs, and it’s totally worth becoming a member.

So, in early spring,

  • Finish pruning your fruit trees,
  • Prune your roses
  • Take hardwood cuttings (Hydrangea, Willow, Dogwood, Holly, Vines )
  • Coppice your dogwoods (cornus) and willows (salix)
  • Prune your hardy evergreen hedges (Boxwood, Ilex, Osmanthus
  • Cut back the ornamental grasses (Miscanthus, Calamagrostis, bamboo) and maybe even your lawn, assuming you didn’t plant crocuses in it.
  • Cut back your hardy perennials and over-wintered geraniums to remove old foliage and let the fresh spring growth start.

2.  Manage Seedlings

My seed starting inspiration comes from:

  • NW Edible Life for Vegetables – Always well researched and entertaining.
  • Floret Flower Farm for Annual Flowers – put on a kettle; you’ll be drowning in colorful photographs for a while; so necessary to keep the winter blahs away.
  • Seattle Tilth’s Maritime Northwest Garden Guide, newly updated by my friend Lisa Taylor.  Her local knowledge and hands-on experience is tremendous.  The variety recommendations alone are worth the book.

Don’t forget to prevent new seeds.  Keep on top of the weeding now, especially that Cardamine hirsuta.  Fairly tasty, I prefer to feed this bittercress to the chickens (also known as chickweed; see A Charlotte Garden for the botanical differences.)

3.  Build Stuff

This year, I want to build a bunny hutch, an English cold frame with recycled bricks, more tuteurs, and a lot of new paving for our permeable driveway.  Ambitious?  Truly.  At least I’m not repairing the chicken coop again, right?

What are you doing this spring?

Late Winter Reminders for Pacific Northwest Gardens

I get frustrated with gardening books.  There are so many books and websites that target the beginning gardener, and plenty of obscure titles that target gardeners who geek out over a single genus.  The ones for advanced readers seem to need a degree or two to understand, while basic ones mainly copy and regurgitate other references already out there.  The first half has pretty pictures but no new techniques, and the last half of the book is a big fat encyclopedia that duplicates the information in all the other books I have.  There aren’t good one-stop-shopping resources for that middle-gardener.  Of course a book like that would be several inches thick.  Or cover a table-top.

A Partial Garden Book Library | #eTilth (c) Lynne Harrison

[Here’s my mom’s partial garden book library.  My library is only a fraction of this size. Thank goodness I get to borrow from this, with generous check-out privileges!]

I’m not likely to make a significant dent into the Gardening 2.0 literature, but I sure wish I had a calendar that kicked me in the butt to do the tasks that I’ve been neglecting.  My biggest problem is thinking ahead several months … if I want Dahlias in summer, I’ld better pull last year’s out of storage now.  I have to throw out the ones that didn’t make it, order more, and start forcing them for cuttings.  Hanging baskets this year?  Better order and start the seeds.  Crud, the apple trees are starting to swell, do I prune, or did I miss the pruning-window again this year?

I always panic a bit knowing that I’ve forgotten some essential task in the garden that just screws me for the rest of the year.

So, inspired by my friend Erica at Northwest Edible Life, here’s my attempt to solve that problem. Pin for later:

Late Winter in the Ornamental Garden | #eTilth


Membership Renewals

I try to renew all of my garden-related memberships at the start of the new year; it keeps the business record-keeping simple.  I tend to procrastinate over the three or four “Renew Now” notices and panic a bit when I get my “Final Issue” … did I send the check and it just crossed paths in the mail?  Here are my top recommendations for memberships:

Oh crap, did I order that?

Of course, all the best gardeners placed their orders in late fall and are sitting smugly, gloating over those lovely seed packets.  Right?  Problem is, plant lust kicks in and I just have to have that hot new thing.  Or that old-but-new thing you just have to try.  Matt Mattus, I blame you.

Friday Tidy

This is the mantra in the summer perennial border.  Spending one day a week trimming back plants and sweeping edges will do wonders.  It’s a little impractical to pick a day by the calendar in the winter; for sure it will be raining.  Instead, take those few dry hours whenever they occur to clean up.

  • Clean out the gutters and unclog storm grates.
  • Clean out your greenhouse (or polytunnel, or cold frame, or garage, or windowsill) to get ready for the growing season.  Wipe down surfaces, clean out old pots.  Prepare new potting soil.
  • Wipe down winter containers, and if you haven’t already, lift them up on pot-risers to ensure drainage.
  • Prune dead wood from fruit trees and shrubs.  Large-flowering Clematis blooms on 2nd year vines; check pruning guides from the experts.
  • Prune fruit trees, and ornamental deciduous shrubs.  Join Plant Amnesty for more guidance.
  • Trim off Hellebore leaves and burn them (or tie off and dispose of in the trash, not municipal waste); they harbor the botrytis fungus which will splash onto the flowers.
  • Replace tired flowers in your winter containers with cyclamen, pansies, and primroses.  You can even sink those narcissus and tulip bulbs you forgot to plant deep into the pot for some late-spring color.
  • Apply mulch to your garden beds … chicken-n-chips and steer manure will kick-start spring growth in perennial beds.  Use arborist chips under trees and shrubs, and on pathways.

Like we actually need an excuse to go plant shopping?

You can force Paperwhites, Hyacinths or Amaryllis for a late-winter pick-me-up.  Go shopping for winter-fragrance shrubs like Daphne bholua (the longest blooming daphne from late October through January), Sarcococca, and Hamamelis so you can choose them in bloom.  Don’t forget to drop in a few Primulas for a pop of color!

Primroses in spring | #eTilth

Let it rain, let it rain, let it rain

The weather in Seattle certainly isn’t frosty this Christmas. In fact, we’ve received over 10 inches this month, the wettest December in nearly a decade

Wet Seattle NOAA Screenshot
(source: http://w2.weather.gov/climate/index.php?wfo=sew retrieved 12/24/15)

But this doesn’t actually seem very different from last year, nor the year before that.  Our backyard routinely floods in high weather events.  You can see where we ended building the path to the chicken coop last year.  We installed perforated piping encased in fabric and gravel at the base of the vegetable garden, and diverted it under the path, connecting it to a 4′ dry-well that we filled with gravel.  But still, the water exceeds the holding capacity of the well.

Enormous puddle at the end of a sidewalk
Where the sidewalk ends

What is interesting is that this new path is 6″ above the old one, which now is always underwater.  Clearly, the water table is higher than at least the 1980s, when we estimate the landscaping was completed by the previous homeowner.

Standing on the old path
Standing on the old path

I cringe at the thought of my water-main shutoff, located in the sidewalk, freezing in a storm (blizzard of 2008, anyone?):

Underwater water main shutoff. Ironic?

What changed?

It’s cavalier of me to claim it is due to climate change, and easy to blame Seattle Public Utilities’ Infiltration Reduction Pilot Program.  The flood-grouting pilot project sealed the aging sewer infrastructure which was installed in the 1950s, when there were fewer homes, more trees, and less pavement.   Now that the storm-water is prevented from entering the sewer system, it flows down streets and sidewalks, into homes, and certainly doesn’t drain as quickly from our back yard.

Nor does it drain well from anyone else’s:

Source: June 2014 Display Boards
Source: June 2014 Display Boards

What to do?

Pointing fingers isn’t going to solve the problem.  SPU is working with the community to develop solutions.  At present, taking into account the nearby bluff and fragile Piper’s Creek watershed that drains through Carkeek Park, the solution is likely to be a system of neighborhood storm-water cascades instead of retention ponds.  Unfortunately, construction is several years hence.

Storm water Cascade NW107th
Storm-water Cascade at NW 107th

Taking Responsibility

This fall I enrolled in a Permaculture Design course which spent a lot of time studying watersheds, drainage, and techniques for moving water across the landscape to make deserts thrive.  John D. Liu’s Green Gold documentary was totally inspiring, but solves the opposite problem!  [5 Min Teaser.]  Water conservation, at least in the winter, is not a major concern.

But let’s not delude ourselves.  In the Pacific Northwest, we live in what is called a modified Mediterranean Climate.  This means that we suffer from enjoy a Summer Dry / Winter Wet weather pattern similar to central Chile, South Africa, and Tasmania.  That’s why plants from those places tend to do so well in our gardens.

So, the trick is to capture and store our winter rainfall to use in the late summer.  The first thing to do is to determine how much water actually falls on our house.  The math here is pretty simple, just measure the perimeter and ignore the slope of the roof.  I was curious however, how much water was directed into each downspout, so I broke the roof into parts and did a lot of estimating.


With approximately 1900 square feet of roof, it turns out that we can collect 40,000 gallons of water every year!

CautionCaution: Math!  1900 square feet of roof * 1 foot / 12 inches * 7.48 gallons water per 1 cubic foot * 37.5 inches rain in a Seattle year * 0.9 coefficient of water loss on an asphalt roof = 40,000 gallons

Four of the downspouts, A, B, C and G are encased in concrete, and dive under the driveway or patios.  We will have to think carefully about disconnecting these downspouts, since the overflow can’t just drain onto the ground at these sites.  We plan on installing cisterns to collect water from D, E, and F, but we want to build the overflow section before investing upstream.  Small changes, baby steps.  Meanwhile, you can see the runoff from the driveway, and downspouts E and F drain into the lawn where the water sits.  And sits.  The lush green grass thrives in a single stripe down the middle.

Drainage Patterns
Drainage Patterns

So, this winter, we are working on clearing out the overgrown blackberries to do some site preparation for our future rain-garden.  We’ll do a percolation test to determine if we’ll need to add more woody organic matter to soak up the water, talk to the neighbors “downstream” of us to determine where our overflow can go, and remove more blackberry roots.  There isn’t much we can do while the soil is saturated without destroying the soil structure, so we’re pouring over planting plans and calculating how big the rain garden will need to be.  My favorite part?  Coming up with plant lists.  It’s never hard to shop for plants.

Rain Garden Resources:

Oregon Rain Garden Guide (free low-resolution PDF)

Rain Garden Handbook for Western Washington (free PDF)


Dunn Gardens in Spring

There is much to write about since last we met; suffice to say that more will be forthcoming. In summary, the front lawn is gone, a new fence is built, the path is ripped out, but must be replaced before the Seattle Tilth Chicken Coop Tour in July, both the vegetable and cutting gardens have been sown, and a costume has been sewn for the Dunn Gardens Edwardian Garden Party in August.

I have barely enough time to take photos, but escaped on a rainy Sunday to visit the Dunn Gardens in March. Here are just a few for the Gardening Gone Wild Picture This photo contest, with no time to annotate now.  I still am not satisfied by the color balance; it’s a borrowed Nikon and it was raining.

[Update 6/13/15 – Yay, I won a photo contest!  It’s an honor to be appreciated by successful photographers.  See below for the winning image.]

An unusual and elegant color combination by Glenn and Charles
An unusual and elegant color combination by Glenn and Charles
Framed Pithos | #eTilth
Pithos framed for Saxon
A closer look
A closer look

Yay! I won a contest!  The above image, Erythronium with a pot, won the Gardening Gone Wild Spring Photo Contest 2015!

Erythronium detail
Erythronium detail

Understanding Soil Tests – Part 1

Two small scoops of soil showing the color difference.

A few years ago, I was obsessing over getting backyard chickens. “For the eggs, honey” I said. Really I meant, “for the poop.” But you can’t quite convince a skeptical spouse with that reasoning. Now that I’ve kept chickens for several years, I have been curious to see the effect of using the composted deep litter on my vegetable garden and compare my actively managed soil with my native soil.

Soil is surprisingly complex, so this article covers the basics of soil texture, pH and organic matter.  The second article covers macronutrients (NPK), secondary nutrients (S, Ca, Mg), and micronutrients (Zn, Fe, Cu, Mn, B, Mo, Cl), and information on how to adjust their amounts.

Farm Tips for Homeowners

This year, I’m taking an Extension Farm Class, and had a fantastic opportunity to learn how to test my soil. Although each farm was only allotted one sample in class, I discovered that King County gives each homeowner FIVE(!) free soils tests. Dig around on your county’s Conservation District website to see how to take and submit soil samples.

Shovel of soil with ruler


Ideally, take several 1” cores, about 6-12” deep, until you have about 2 cups of soil. You can use one of these fancy soil-samplers, but a shovel works just fine.  I dug a narrow slice of lawn from three separate sites in the front yard, knocked off the edges to make a 2″ x 2″ x 6″ core. I discarded the grass, mixed everything in a bucket, and sieved it through a ½” hardware-cloth screen to remove the worms and stones. I repeated the process in my vegetable garden, taking care to keep the samples separate.  I put each sample in a pyrex pie plate and gently dried them in the oven for a couple of hours … just barely warmed to 150oF or so. [Edit: I should have just air-dried these; heat can be detrimental to getting an accurate reading.] There was an obvious color difference between the greyish lawn sample and the dark vegetable garden sample. Then I packaged them in zip-lock bags, labelled, and mailed them off to two different testing laboratories, A & L Western Agricultural Laboratories (King County), and Soil Test Farm Consultants (Snohomish County).

Delightfully, the results came by email within a few days.

And they made no sense. Now what?

Picking Apart the Report

Interpreting your soil test results can be as dry as … well, dirt. But, let’s start with the basics:

Soil Texture:

There are three kinds of soil particles organized by size: Clay (less than 0.002 mm), Silt (0.002-0.05mm), and Sand (0.05-2mm), and the percentage of each of these makes up your Soil Texture. Well, actually, you’ll also have gravel. And sticks and twigs. And worms. And endless numbers of big-ass stones.

Your soil test probably won’t calculate these values for you, but you can put some of your screened soil (no worms, please) in a straight-sided jar with some water, shake and let settle. Then get out your ruler and measure the thickness of each layer. Do a little math, and you can figure out your soil type. The ideal texture for crops is a medium loam, about 20% Clay, 40% Silt and 40% Sand (see where the lines intersect in the chart below).

Triangle shaped graphic showing percent of clay, silt and sand

Ph-iguring out pH:

The next important item to understand is pH, which is a measure of how acidic your soil is (pH stands for ‘Potential Hydrogen’). Plants grow best when nutrients (chemical elements) in the soil are available for their growth. Nutrients are bound to soils or wash away, if the soil is too acidic or basic. The optimal range for most crops is a pH between 6 and 7.5.

Diagram showing pH ScaleMy soil tests came back with a pH of 4.6 in the lawn (acidic) and a pH of 6.4 (optimal) in the veg garden. Typically, if your soil is high in clay (small particles which hold onto many hydrogen atoms), or in a rainy climate (which washes away most of the other cations like Calcium and Magnesium), then your soil will be acidic. Since I live in the Pacific Northwest, this was no surprise.

Diagram of pH values in reportYou may also get a value for buffer pH, which is a laboratory-defined value based on how much the pH of the sample changed when they add a standard amount of lime to it.  Buffer pH may also be labelled SMP, named after the people who developed the test – Shoemaker, MacLean and Pratt.  This means that my lawn, with a buffer pH of 6.1, holds onto acidic particles much more strongly than my vegetable garden, with a buffer pH of 6.3.  It will take more lime, therefore, to change the pH of my lawn. Based on your soil type and the types of crops you want to grow, follow the recommended amounts in your lab report [See the OSU Soil Test Interpretation Guide].

table 10 from soil test interpretation guide showing how much lime to add per 1000 square feet

My lab, A & L, suggested that I add 180 lbs of Dolomitic Lime ( CaMg(CO3)2) per 1000 square feet to the front lawn. You could also add Agricultural Lime (CaCO3) which comes from chalky deposits high in calcium, but doesn’t contain as much magnesium. The ideal time to add lime is in the early Fall, but lime takes time to be incorporated so don’t add it all at once. Conveniently, my front lawn is exactly 1000 square feet; I’ll add 50 lbs next October, and the same again for two more years, testing each year to ensure I don’t over-apply it.

Note: if your soil is basic, you can add elemental sulfur to bring the pH down to neutral.  Clay-rich soils require more sulfur (40-50 lbs/1000 square feet) than sandy soils (10-20 lbs/1000 square feet)

Organic Matter:

The next part of the soil test report you should look at is percent organic matter. Typically, you should expect a Soil Organic Matter (SOM) percentage between 3-5%, but 2.5% is fine in sandy soils, and 10% is common in clay soils in cool, rainy climates. Organic matter provides a good reservoir of nutrients and increases the water-holding capacity of your soil. I got an okay reading of 5.1% for my lawn and a whopping 17.1% in the veg garden! Way to go, chickens!

Diagram comparing percent organic matterI should add, however, that it is okay for me to add organic matter to my vegetable garden because I am actively growing crops on this soil, and by definition, removing organic matter every time I harvest a head of lettuce. However, 17% is way too high for landscapes. A better way to manage my front yard is to top-dress permanent plantings (trees and shrubs) with wood-chip mulches which will decay nicely over time. You can read more about this topic by Linda Chalker-Scott on her Horticultural Myths, page, in the Soil Amendments section.

In the next article, you’ll learn about how to understand your macro- and micro-nutrient amounts and how to adjust them.  Until then, you can read how plants get nutrients out of the soils on my Hobby Farms Article.