Calgary Garden Coach

what to do with clay soil?

Yikes.  This is the worst garden soil I have ever seen!  There is maybe 10-15 cm of topsoil in this garden, and underneath is pure Calgary clay.  Whoever landscaped this yard ripped the homeowner off.  Fortunately for me, it's not my soil.  But what to tell my client?

There are two ways to improve garden soil.  A good 30 cm of topsoil is required for plants to really thrive.  45 cm would be even better.  The best way is to get this is to get a Bobcat in to remove the existing soil down to at least 30 cm and have it replaced with good black loam.  This is great if you are starting from scratch (and if you are, then I highly recommend doing this!  You will not regret it), but if you already have an established yard or just want to add a few plants here and there, it's not very practical. 

The other option is to improve the soil as you dig each hole and plant each plant.  Faster in the short-term but possibly more work in the long-term.  So, in this garden, I dug each hole 3 times bigger than the size of the pot that the plant was in (what a workout!), and mixed lots of compost with the existing soil in each hole.  This will make space for each plant to grow its roots into without struggling in the hard clay.  Top-dressing the whole garden with 2-4" of compost each spring will also gradually help improve the garden soil.

what to do about powdery mildew

Sigh. Why do I keep these Jacob's ladder plants?  Every year they get powdery mildew - the leaves look like they have flour dusted on them, and they eventually die to the ground and look horrible.  They get a fair amount of sun, but maybe not enough air circulation due to being planted right beside the garage?

I may try moving them to a new spot next spring and giving them one more chance...

Preventative measures for powdery mildew include giving space for air circulation, and keeping foliage dry (i.e. not watering in the evening).  A spray of 1 tsp baking soda and a drop of dish soap in 1 L of water will also stop it from spreading.

plants deer and rabbits don't love

Nothing is guaranteed, as deer and hares may eat almost anything if they are hungry enough, and once they find a garden they like, they tend to return again and again.  Also, some things may be location dependent - I've read that hares don't eat yarrow, but they do in my front garden - just the flower buds!  I don't have a problem with hares in the back yard, as I have a dog, but I have a friend who says planting lots of onions in the veggie patch seems to keep the hares out.

If you live in the country, the only real way to keep deer and hares out is a fence.  But in the city, deer and hares generally avoid plants with silver or grey leaves, and plants with fragrant, hairy, leathery or prickly leaves.  Here are some plants that will likely discourage them:

• aconitum (monkshood)
• agastache (anise-hyssop)
• aquilegia (columbine)
• artemesia (ornamental sage)
• aster
• cerastium (snow-in-summer)
• dicentra (bleeding heart)
• digitalis (foxglove)
• epimedium (bishop's hat)
• euphorbia (spurge)
• filipendula (meadowsweet)
• gaillardia (blanket flower)
• perennial geranium (cranesbill)
• kniphofia (torch-lily)
• lamium
• lavandula (lavender)
• leucanthemum (shasta daisy)
• lupin
• monarda (bee balm)
• narcissus (daffodils)
• nepeta (catmint)
• penstemon (beard tongue)
• peonies
• salvia (blue sage)
• sedum (stonecrop)
• stachys (lamb's ears)
• thymus (thyme)
• yucca

how long does it take to smother grass?

2 months in spring, apparently.

This is the spot where 5 cubic yards of compost was delivered this spring!  It was delivered April 14 and I didn't get around to finishing moving it until June 15.  A month and a half later and the grass is only just starting to grow back!  (Normally I wouldn't have left it so long but I was busy with a big renovation/replanting project in the backyard.)

The neighbours might not be too impressed but I don't really mind the bare spot because this area is destined to be garden in a year or two anyway.  The only problem is, where am I going to have my compost delivered in the future...?

how to stake delphiniums

OK, just because I know how to stake delphiniums, it doesn't mean I actually get around to it!!

These are my absolute favourite flower.  The electric blue shades are stunning (they flower in other colours too - white, pink and more but why bother when the blue is so gorgeous?).  I'm also very happy that my experiment planting them on the north side of a fence where they get about 2 hours of sun a day worked!!  Delphiniums supposedly love sun but I've always grown them in partial shade - they flower just fine and require less water this way.

Unfortunately, staking them is a bit of an art.  There are several ways to do it:

1.  The fairly easy way.  Since you need to stake them long before they flower, put tall stakes in early.  Loop some garden twine around the stakes, making a circle around the plant, just under the top of the plant.  As it grows, add more loops of twine higher up the stake.  One problem with this method is that you have tall stakes sticking up way above the plant before it gets tall enough to hide the stakes.  Also, if you don't stake each individual stem, you still risk them flopping over within the area of the twine if the flowers get too heavy.  Sometimes I just cut the flopped ones and bring them inside in a vase.

2.  The perfectionist's way.  Place several stakes around the plant before it gets too tall.  Use small loops of twine around each stem, and tie each stem to the nearest stake.  Repeat this higher and higher up the stake as the plant grows.  If you're really anal, you can even replace the stakes with taller ones as required, so you don't have bare stakes sticking up way above the plant early in the season.  Nobody ever said perfect delphiniums were easy.

how to get rid of ants?

A few ants in the garden are not a problem.  However, if they decide to make a large nest right near the root system of one of your plants, then they could damage the roots and even kill the plants.  Most ants like it dry, so they can also be a problem under patio stones, under eaves or in rock gardens (carpenter ants nest in moist areas but are not very common unless you have a lot of rotten wood in your yard like me - more on that some other day!)

One solution I've tried is to pour boiling water on the ant hill.  This works fairly well especially in patio areas, although you may have to do it a few times.  However, if the ant hill is near a plant, you don't want to risk damaging the plant, too. 

A week or so ago I heard someone on a radio call-in show give a tip about cream of wheat - spread it around the area, the ants will eat it and it will expand in their stomache and kill them.  I thought it was worth a try so I'm trying it!  I will report back if I get any results.

what is the best edging to use between lawn and garden?

A trench is easiest and most effective.  If you make a nice vertical cut like this all around your garden, and let the soil on the garden side gradually slope back up again to ground level, the grass roots will have nowhere to spread.  Redo the edging once every spring and maybe once later in summer if you're a perfectionist, and that's it.

The black plastic edging stuff isn't worth it.  It's a pain to install properly, it often heaves from frost, and you'll still have to pull up grass that jumps over it here and there. Not including installation, you'll probably spend the same amount of time keeping grass out of your garden as if you just re-cut the edge every spring.  Plus, moving the plastic edging is a pain if you want to change the shape of your garden bed and finally... it's plastic in the garden!  Who needs it?

A brick or rock border looks nice, so go for it if you want, but keep in mind it will not be low maintenance.  The grass is going to keep spreading into the cracks between the bricks and it's even harder to pull out once it's in there.  And again there's the problem of changing the shape of your bed. 

Seriously.  Cut a trench once a year and you'll be happy!

where's the best place to buy plants?

I wish I was virtuous and could say that I only support the locally-owned garden centres with my gardening dollar.  But I can't!

I would say that where to shop depends on the time of year, your gardening experience, and what you're looking for.  Here are a few comments to help you decide:

Garden centre:  will generally have the most varied selection, well-organized and easy to find things, staff that can answer questions.  Plus, the plants are kept in a greenhouse so are less likely to be stressed (see below).  If you are an avid collector, the smaller garden centres will often carry more specialty and hard-to-find plants.

Big box stores: are usually cheaper but generally carry only the most popular plants (which is probably a good thing for the relatively new gardener), are typically not well-organized and... try to find someone to answer a question!!  I find plants are quite healthy in early spring (i.e. May) when shipments first start coming in.  Later in the summer, after the plants have been sitting in makeshift shelters on a parking lot and have been "cared" for by untrained staff, they're not such a great deal.  However, if you happen to drop in right after a shipment has come in, you can still luck out.

Since I work full-time and have a young family, I don't have much time to shop around much.  I got all of my perennials in early May this year from Canadian Tire and Superstore because they're close to my house and I happened to need other things from those stores (to be honest those other things were probably excuses shop for plants).  Canadian Tire carries some Alberta-grown perennials (look for the blue pots) so I feel like I'm still shopping somewhat locally. 

how to prune roses

In keeping with my low-maintenance, sustainable philosophy, I only grow hardy shrub roses.  The less hardy tea roses are beautiful but I just can't be bothered.  Hardy shrub roses will make it through the winter in zone 3 with no extra care.

However, some years they will experience quite a bit of tip kill.  And if they don't, you'll want to thin them out occasionally to keep them healthy.

People are always afraid to prune roses, but it's not hard.  Here are a couple tips:

Always cut just above an outward facing bud.  That bud is going to grow into a new branch, so you want it to grow towards the outside of the plant, not cross over the inside.
Remove any crossing branches.

Remove any weak, thin branches to direct more energy into the stronger ones.

Voila!

what to plant in full shade?

There is shade (less than 2 hours of sun) and then there's shade (absolutely no direct sunlight).  Even most garden areas on the north side of a building or fence will receive at least a little morning and evening light.  But if you also have large trees, especially evergreens, an area may actually get none at all.  Here are a few of the solutions I've given people recently:

Pots

Pots can be placed anywhere - why not plunk them in the garden if you have a troublesome area - they add instant height and also you don't have to worry about what kind of soil you have (especially good around spruce trees).  Don't be shy, use big ones!!  This pot is in a dark, corner of my garden by the back gate.  It is also under a giant spruce tree.  No sun.  But I wanted something to mark the gate and I can also see this spot from the kitchen window so wanted to lighten it up a bit.  I have done well in the past with impatiens (annual flower, filler) and variegated english ivy (foliage, spiller).  Not very original but these are challenging conditions! 

This year I am doing the pot as an afterthought (I've been busy), so I used what I had lying around the house: a variegated spider plant (house plant), oxalis (annual, green and burgandy clover-shaped foliage, probably won't flower in full shade, leftover from a Safeway purchase at St. Patrick's day) and a couple impatiens (on the right, not blooming yet, OK I bought those).  I also used a couple of extra doo-dads I had lying around from a craft store - a couple of round things on sticks (no idea what they are but they're not plastic - definately dried plant material of some kind), and some of those curly sticks as well (click on picture to see a little better).  Gotta think outside the box in full shade!!  Other plants to try include begonias (filler, annual flowers, or rex begonias for fantastic foliage), coleus (filler, annual for colourful foliage) and lamium (spiller, a perennial for foliage that can be planted in the garden at the end of the season).  Some sedges (annual ornamental grass, thriller) are shade tolerant but I've never tried them in full shade.

Perennials

I have one area north of my garage that is full shade.  The plants a little further out get at least dappled shade, but close to the garage gets nothing because of nearby trees, fence etc.  Keep in mind that even shade-tolerant plants are not going to thrive here - they may grow but not get as big nor flower as much as they would if they got at least a little dappled light.  Ligularia, astilbe, bleeding heart and aruncus dioicus (goatsbeard) are all surviving but I wouldn't say thriving in my full shade garden.  Hostas might be ok too, although mine are further away from the garage and get some light.  These are all plants that like moisture though, so keep on top of the watering, especially if the reason you have so much shade is because of nearby trees. 

Perennials for dry shade would probably survive but not thrive as well, but I haven't grown any of mine in full shade so can't speak from experience.  Keep in mind that plants for dry shade tend to be shorter, ground-cover-ish plants with smaller flowers, so not as showy or dramatic as the moisture-loving ones.  Maybe plant a ground cover and arrange some pots in the middle...? 

I have also heard of clematis tangutica (a tough, perennial, yellow-flowering vine) growing in full-shade, but haven't tried it myself (although I might...).

what causes yellowed foliage?

While the yellow foliage of my John Cabot climbing rose contrasts nicely with the blue wall behind, it's not supposed to be yellow!

I actually have quite a few plants in one area with leaves that are turning yellow.  I suspect the problem is the roots left over from a giant willow tree we had taken out a couple of years ago.  The rotting wood in the ground is using a lot of nitrogen, meaning less available for the plants.

Another common cause of yellow leaves with green veins is iron chlorosis, caused by a lack of available iron in highly alkaline soil.  If you see this, you can get chelated iron, which is mixed with water and applied either directly to foliage or watered into the soil.  Acidifying fertilizers also help, such as blood meal and fertilizers with sulphur.  Cut off a few leaves and take them to a good garden centre and ask for advice, or consider getting your soil tested.

how to propagate native moss

Moss makes a nice groundcover and adds instant "age" to a garden.  It needs some shade and a spot that stays fairly moist.  If you already have some growing and want to spread it around, it takes a little time but is very easy.  Here's what to do:

Scrape up about 1 tsp of the moss, and mix with 1 cup of buttermilk, yogurt or beer (!) in a blender.  Paint the mixture onto a rock, pot, wood, or wherever you want it to grow.  Mist it several times a day for about 3 weeks.  That's it!

how to plant perennials

Here's my back hill renovation in progress.

Design tips

Besides the basic rules of "place sun-lovers in sun and shade-lovers in shade" and "don't plant one of everything", the key thing is to make sure you leave enough space between plants.  Sure, those perennials are small right now (especially if you buy the cheap ones, like me), but check the tag to see how big they are going to get and resist the urge to pack them in too tightly.  Plants that are too close together may lack air circulation and be more susceptible to diseases such as powdery mildew, not to mention the fact that in a couple years they'll be too big and you'll have to dig them all up again.  If you like the tightly packed look, throw some annuals in between to fill the spaces for a few years, otherwise add mulch to keep the weeds down.  In a few years when the plants are bigger, they'll cover the bare spots and keep the weeds down themselves.

Planting tips

Plant in the morning or evening or on a cloudy day, to reduce the stress on the plants.  Dig a hole twice the size of the plant's pot and throw a couple of handfuls of compost and one handful of bonemeal in the bottom of the hole.  There, you've just fertilized your plant for the first year at least.  If the plant is rootbound, loosen the roots before planting, then back fill with the soil.  Be sure to water plenty in the first few days after planting, and regularly for the first year until the plant is well-established. 

what can I grow under my spruce tree?

The problem with trying to grow something (including grass) under a spruce tree, is not the acidic needles (they don't affect the soil much and Calgary's soil is alkaline anyway), but that it is dry, dry, dry.  Not only do the branches prevent much rain from reaching the ground, but the extensive root systems suck up all the water around the tree. 

In my opinion, the best thing to do is to put down some mulch (bark chips or shredded bark), and let the cones and needles fall where they may.  Don't let someone tell you to plant moisture-loving shade plants such as hostas and ferns under a spruce - you will be doomed to failure (sorry Melanie and Megan, if you're reading this)!!  If you really want to try to grow something (good luck and be prepared to water), try something that is extremely drought tolerant:

for sun:

• snow-in-summer

for shade:

• epimedium (also called barrenwort and bishop's hat)
• lamiastrum
• goutweed (but beware it will spread invasively if it is not contained)
• lily of the valley (same caveat as above)

what is hardening off?

As soon as it is nice (above 10 degrees), you can start putting your seedlings or greenhouse purchases outside.  The plants are very tender, or "soft", from being grown in an indoor environment.  If you started your own seedling, they may also be getting a little leggy (stretched) from not enough light.

But you can't just put them outside in full sun right away - well you can, but they won't like it!  They will burn - just like me (fortunately, I remembered to put sunscreen on yesterday!). 

So set them outside in a sheltered location (shade and shelter from too much wind).  Start with 30 minutes in shade, increasing to a couple hours over several days.  Then start putting them in sun for 10-15 minutes each day, increasing by 15 minutes per day, then back in the shade.  The sun and breeze will harden them up.  If you have perennials, they will be ready to go outside in a week or so.  The traditional date for planting annuals outside is May 24, but you can plant them earlier if you're willing to cover them up or move pots inside anytime there's risk of frost.

Sounds like a lot of work, I know.  But it's only for a week or two and your plants will thank you by not going into shock. 

taking care of tomatoes

Here are some of my tomato babies (with our beautiful april snowfall in the background). They grew too tall for my seed-growing space in the basement so now they are sitting in my sunroom window. Technically, even a south-facing window isn't really enough light, but this is a sunroom with windows on three sides so I'm breaking the rules for a few days. Soon they will be going out to the unheated greenhouse, with lots of insulation and with me keeping my eyes on the weather forecast!

Here's what you should be doing with your tomato seedlings this month:

• after they have their first set of leaves, water with a dilute fertilizer (half-strength, twice as often)
• keep them under grow lights (one warm and one cool 40W flourescent tubes will do), with the lights always just a couple inches above the plants (if you have to put them in a window, keep turning them so they grow straight)
• repot them again before they will go outside (you can see I've done some of mine) - plant deeper each time and new roots will sprout along the stem, resulting in a stronger plant
• for indeterminate (vine) types, pinch off the sprouts that grow in the crook of each branch as soon as they get big enough to handle (see below).  these extra branches will take energy away from the plant (for determinate types you don't need to pinch.)

How do I take care of my lawn?

Well, if you must have a lawn, here are some tips:

Aerate and power rake in spring

The typical advice out there is to aerate every year, but if you have a newer lawn or one that has been well taken-care of, you can probably get away with every other year.  Mine is very old and compacted, and definately needs aerating every year.  The plugs can be left to decompose on the lawn, or raked up and thrown into the compost bin for a great compost stimulator.  The occasional power rake isn't a bad idea, either, if your lawn is very thick.

Fertilize

One of the best things you can do is spread about 1/4" of compost over the lawn every spring (May or June).  If you are aerating and/or power raking, apply the compost after.  Soon the grass will grow into it and you won't even know it's there, meanwhile it is a slow release fertilizer that will feed your lawn and even any nearby trees.  There are companies who will deliver compost and even spread it for you if you choose.

Puh-lease don't use weed and feed unless you really have a terrible weed infestation!  It's such a waste and just environmentally unacceptable these days.  If you insist on using synthetic fertilizer, wait until mid-May when the ground will be warm enough for it to activate so that it won't just run off into the sewer with the next rain.

Water

Unless you have a need to be the first on the block to have a green lawn, you don't need to water until mid-May either.  After that it needs about 1" per week (or enough to fill an upside-down frisbee) - that includes rainfall.  The current environmental advice is to water less frequently and deeper to encourage the grass to grow deeper roots and make it more drought tolerant.  It's also best to water in the early morning when there is usually very little wind.  You can buy timers for your sprinkler if you're not a morning person!   But even better, we need more awareness that grass will naturally brown in the hot summer, but not die.  It will green up again in the fall when weather gets cooler so there is really no need to water like mad in the middle of the summer.  In a few years it will probably be banned anyway.   

what kind of mulch should I use?

I'm talking summer mulch here, not the kind used for insulating tender plants over the winter.

Mulching your garden will help to conserve water and suppress weeds - definately a sustainable choice for both the environment and your enjoyment of your yard!  Basically, there are 2 types - the permanent kind and the kind that must be replaced every few years.  But wait, don't make a decision yet...

Permanent: rocks, gravel, shale etc.  These mulches do the job.  Pea gravel and other gravels are trendy right now and look especially nice in a xeriscape garden (lots of drought-tolerant plants that like the heat absorbed by the rocks).  However, there are some major cons:

• Look at all the dust, soil and dead plant material that must be cleaned off every year to keep it looking good.  If you don't, then eventually there will be enough matter there for weed seeds to take hold and you've defeated the purpose of the mulch.  Somebody mulched my whole yard with red shale about 20 years ago, and I am still cursing them.  It's not in style anymore and I spent my first summer in this house digging it all up because it was dirty, dusty, and I wanted more room for plants.  Don't put down a permanent mulch unless you're sure you won't want to change it... ever.

Non-permanent: bark, shredded bark, compost, etc.  While these types of mulches do need to be replaced (the smaller the pieces, the faster it will break down), they also do the job of fertilizing the soil while they decompose.  So voila, you've also fertilized your garden the way nature intended!  However, barks break down slowly and also draws some nitrogen out of the soil for the decomposition process, so it is still recommended to add compost (or other organic amendment) as fertilizer.  That means you have to rake off the bark mulch, topdress with compost, and add the bark back on top again.  Ugh.  Why not just use compost?  It is easy to apply, you can make it yourself (although I always need more) and it looks great - like a professionally tended garden without a weed in sight!  Well, at least for a while...

So depending on the style of your garden, your taste and your willingness to spend the time, the final decision is up to you.  This year I am using shredded bark mulch for the pathways in my garden (because I don't have to worry about fertilizing them) and compost everywhere else, including my small patch of lawn. It's a bit of work in spring to spread the mulch (but of course this is when I am most keen to be doing major garden work), and then your work is minimized for the rest of the season.  And if you don't like it, you can change it next year - just don't add 3" of red shale... please!! 

What to do with Easter flowers?

If you're like me, you can't bear to throw a plant away if it could possibly survive in the garden. 

I love having hyacinths in the house because their perfume is so amazing.  But these will be better off in the compost bin than the garden. 

The bare bulbs you can purchase for planting are borderline hardy in Calgary, but the plants often don't survive and if they do, they are so top-heavy that they need delicate staking - not exactly low maintenance. 

The bulbs you buy already planted and flowering have been fertilized and forced to the max, and they have expended so much energy they'll never flower again even if they do survive.

  Dafffodils also lift my spirits in spring, and most varieties can be planted in the garden once the ground is workable.  Again, store-bought daffodils have probably been fertilized to the max and they may not flower next year.  But daffodils naturalize (multiply) easily and they will come back year after year - and probably flower again in another year after they have recovered from being forced.  They're worth the effort to try, I think.

One problem with daffodils is that you have to wait for the leaves to die down after they finish flowering.  I hide their dying leaves by planting them around perennials that will grow quickly and cover them up as they wither away.

Easter lilies can also be planted in Calgary gardens once the soil has warmed.  They will come back reliably and flower most years.  Plant in a warm, sunny spot for best blooms.

How do I get rid of my lawn?

There are a number of possible ways and I've tried most of them.  Here are my suggestions based on experience:

• Remove the grass (manually or with sod cutter), add loads of compost and till.  This is truly the best method.  If you're in an older neighbourhood, your soil is probably hard-packed under there.  If you're in a new neighbourhood, you probably have only 6" of topsoil.  Take the time now to prepare your soil and you will thank yourself for it later.

Kill the grass (a. smother with carpet or plastic for a season, b. smother with newspaper and top with a mixture of topsoil and compost, or c. use herbicide and top with soil)

For method a, wait for a year before planting - but it doesn't look pretty in the meantime!   Also, using plastic will kill all the beneficial organisms in the soil.  

For methods b & c, you can plant right away by digging extra-large holes to amend the soil on a plant-by-plant basis.  This works too but is more work in the long run.  Also, in our dry climate, it takes a while for the newspaper to break down (supposedly you can cut through it with a shovel when you plant, but it's been a headache whenever I've tried it).  I don't recommend herbicides for environmental reasons.  Besides, in both cases, you'll be raising the soil level and will constantly having soil falling down onto your sidewalk or patio.  If these disadvantages don't bother you, look for more details by googling "lasagna gardening".

Build raised beds  If the raised bed is at least 8" high, it will take care of the problems of compacted soil or lack of soil as well as soil falling where you don't want it to.  There are many beautiful options to match your house and garden style to contain the raised bed - stone, wood, brick or concrete blocks and more.  Put the newspaper down to prevent grass growing through, and fill with a quality garden soil mix.

What is a zone??

Canada and the US are divided into USDA hardiness zones based on average annual minimal temperatures.  Calgary is officially Zone 3, so any perennial you see rated zone 3 or lower should be fully hardy here.  That said, Calgary is dry and windy, and chinooks are especially hard on our woodies and perennials.  Then again, some areas of Calgary are harsher than others due to elevation, lack of mature trees, etc.  It is also possible to have warmer microclimates in a sheltered spot in your yard, for example a south-facing foundation bed and furthermore, sometimes plant ratings aren't very accurate.  Karl Foerster feather reed grass is a trendy, vertical ornamental grass that you see everywhere but is officially rated zone 5.  Basically, check out what plants are doing well in your neighbourhood, go to a nursery with knowledgable staff, and feel to take a few risks.