It’s not over until it’s over: Fall Planting

Around here, the first real ‘nip’ in the air usually comes in late August. It usually doesn’t last- typically reserved for the hours between dusk and sunrise- but it is always an instant reminder that change is on our doorstep.

I always get excited when the temperature begins to dip. Not only do I love the seasonality of life in Canada, but the cooler air is welcomed with open arms. I am usually pretty ‘done’ with the heat of summer at this point in the year (truthfully I am usually done with it in July) and I am just longing to cozy up in my fleece sweater and sport my favourite hair accessory: the toque.

Shorter days, cooler temperatures, amazing colours… fall is here!

With the change in wardrobe comes a change in garden mindset too- thoughts of removing annuals, cutting back perennials, cleaning up leaves, and erecting snow/wind protection usually comes to mind when we think of fall gardening, but let’s not close out the gardening season so quickly! Fall is also a fantastic time for another fun task… planting! Which, may I point out, generally involves acquiring NEW PLANTS- yippee!

Fall Planting

Fall is a great time for planting for a few reasons:

• The air temperatures are cooler which makes the change in location less stressful on the plant. Cooler temperatures also discourage the plant from sending out top growth (which is ideal since we want new plants to focus on root growth instead).

• The soil is still warm which allows for root growth (and therefore plant establishment).

• There is [usually] more consistent moisture in the form of rainfall. Moisture is essential for the establishment of newly installed plants. When it is generously provided by Mother Nature, it minimizes the need to irrigate newly planted material. Additionally, the cooler temperatures mean the garden won’t dry out as quickly so it will be easier to keep plants properly watered while they get established (proper watering is usually a losing battle in the summer).

• We get a head-start on next year’s growing season. By planting at this point in the year, new plants have a good month or more to ‘put down roots’ giving them a good head-start for next year.

Yippee! New plants! (Rudbeckia hirta ‘Prairie Sun’)

A Word of Caution

While fall is generally a great time for planting, there are a few plants I shy away from installing in the autumn months. They include:

• Broadleaf evergreens such as Rhododendron, Pieris, evergreen Ilex (holly) and Buxus (boxwood). These shrubs retain their leaves throughout the winter months and it is through these large leaves that moisture is lost. With the soil water frozen (and therefore ‘locked-up’), these plants are not able to replenish the water lost from their leaves and the plants then become at risk of desiccating (drying out) over the winter months.

• Other evergreens with needle/scale-like foliage such as Pinus (pine), Picea (spruce), Thuja (cedar), Tsuga (hemlock) etc. While these evergreens are generally adapted to harsher climates and their foliage is designed to minimize water loss, the needles/scales are still areas where water loss can occur. Once again, with roots unable to access the moisture locked-up in the frozen soil, these plants can suffer from winter desiccation. (It should be noted that this is particularly an issue for newly planted nursery stock; once these evergreens are established with a more mature root system, the concern over winter desiccation lessens).

• Plants that are marginally hardy for the location in which I am planting them. The two plants that come to mind are Buddleia (butterfly bush) and Caryopteris (bluebeard). For plants such as these, I want them to have the whole growing season to get themselves established in my garden before they need to face the harsh reality of winter!

Caryopteris- a plant that doesn’t exactly have the best track record for withstanding our winters. For that reason, it is one that I prefer to plant in the spring.

Throwing out the Rules

As with many things in gardening, rules are meant to be broken. In reality there are many amazing sales to be had at the garden centres and realistically, gardeners tend to have a bit more time on their hands in September/October as opposed to the spring (when there is no end to the ‘to do list’). Planting at this time of year makes practical sense.

So what happens if you just happen to purchase some plants that are not-so-ideal for fall planting? Well, there are a few techniques you can use to help ensure the survival of your new additions:

1. Burlap- erect a burlap screen around newly planted trees/shrubs to minimize airflow around the plants (which in turn minimizes the evaporative water loss from the plants and helps to ward-off desiccation). Screens get erected once air temperatures remain consistently cold- usually November.

2. Mulch- Applying a good layer of mulch around the plant protects the establishing root system by providing additional insulation from the cold as well as potentially damaging temperature fluctuations. Mulch also helps to conserve soil moisture.

3. Water- It is important to remember that despite cooler air temperatures, soil can still dry out. For roots to grow and establish, they need moisture so it is important to keep watering newly planted trees, shrubs, and perennials right up until the ground freezes! Proper watering during the autumn months will also ensure your plants are “fully hydrated” entering into the winter. This is an important step in helping your plants survive winter water loss without completely drying out. (A drought-stressed plant is much more likely to succumb to winter desiccation than a property watered plant.). So check your soil often, and when it starts to get dry, be sure to water. With that said, it is important to not keep the soil consistently wet, as this will promote root and crown rot issues in your plants.

Phew! Well that was long-winded! So as you can see, the growing season is certainly not over! On that note, I have a sudden urge to take a walk through my garden and make a shopping list- afterall there are still some ‘must-haves’ that must find a place in my garden this fall!

Happy planting!

A sea of colour… take it in! It won’t last long…

Footprints are for the beach.

What do you see when you look at this picture?

I’ll start by telling you what I don’t see. (Rant alert!!!)

I don’t see a beautiful garden edge.

I don’t see a patch of Geranium x cantabrigiense that feels the same way about the relentless heat we have been experiencing that I do.

Instead, I see 2 big footprints glaring at me from the dirt. Hmmm… mens size 9.5 maybe?

Anyone who knows me, knows that footprints in a garden are a HUGE pet peeve of mine. I am known to walk backwards out of a garden, fluffing out my footprints as I retreat. I am sure it has raised many an eyebrow. I am also known to contort into various awkward-looking pseudo-yoga poses in order to avoid taking a step into a garden bed. (Should we call for help? Wonder the passerbys).

Ahhhh…. just a little fluff of the mulch makes everything better!

As a landscape gardener, I believe that gardens should look like they magically take care of themselves or little garden fairies tend to them while we are sleeping. Therefore when I leave a job site, I strive to leave no trace of my gardening visit. 

Footprints just look awful. They dash the illusion of magical intervention, and they detract from the nice features within a garden. As in the photo above, instead of seeing the absolutely beautiful garden edge made by Mr. 9.5, all I see is the print of a CSA approved workboot. Pitty. 

OK. Rant complete. Now onto something more productive as there are other reasons to not trample in a garden. Repeatedly walking all over a garden bed (especially a wet one) causes compaction of the soil: an all-around bad situation.

Let’s backtrack. 

Soil is made up of a few different things:

1. Mineral components (sand, silt and clay)

2. Organic components (such a living organisms and decaying plant matter)

3. Pore spaces (tiny spaces between soil particles that are filled with water or air)

Now there are entire textbooks devoted to soil. I know- I’ve owned one… and likely slept on it before an exam in the hopes that any unlearned information would somehow transfer into my brain via osmosis. So I am going to try to keep this concise: essentially, the pore spaces in the soil are really important! 

When soil is compacted, the solid soil particles are pressed closer together thus reducing pore spaces. When this happens, there are significant consequences. Here are some of them:

• The soil becomes denser and it becomes harder for plant roots to push through the soil, stunting the root system and negatively impacting the overall growth of the plants

• The soil cannot absorb moisture as easily (which means that rain/irrigation water is more likely to run off the soil rather than infiltrate into it)

• The ability of the soil to drain can be restricted, leading to overly saturated conditions for extended periods of time (not all plants are able to tolerate these conditions)

• Gas exchange between the roots of plants and the soil (needed for biological processes) and also between the soil environment and the ‘outer world’ is compromised which negatively impacts plant growth

• Availability and plant uptake of nutrients can be negatively affected in compacted soils

• Soil processes such as the decomposition of organic matter can be slowed down

Why is it that nothing grows on a hiking trail? Soil compaction is a significant factor.

OK. You can wake up now!

So you probably get the point that soil compaction is a BAD thing… but what’s a lowly weight-bearing gardener to do?

While it is impossible to not walk in a garden, there are some tips to help minimize compaction of your soil:

• Tread minimally: if you can reach what you need to reach without stepping into your garden, harness your inner psuodo-yogi and do it! Additionally, don’t walk through your garden to get to your next task, step out of it and walk around it if possible. Then take the shortest route possible back into the garden to access your next working area.

• Be mindful of the moisture level in your soil: it is much easier to compact wet soils than dry ones. If you need to be walking in your garden beds, do so when the soil is on the drier side. This is an especially important point to keep in mind if you garden on clay soils, which are much easier to compact than sandier soils.

• Designate your walking zones: some gardeners will put minor paths through their garden to act as access points from which they can work without having to step into their cultivated areas. These paths can be as simple as a mulched trail or small stepping stone walkway. Whatever your path of choice, using one keeps the impacts of compaction to a specific area.

• Distribute your weight: some gardeners choose to distribute their weight by placing down temporary planks across the garden on which they walk. Obviously this is not always feasible or practical but it can be a good soil-preserving technique.

A garden that can be accessed by various features such as a dry riverbed (not shown) and rockery.

And thats a wrap!

Soil compaction... an important process that can have significant consequences on your garden and it’s inhabitants (and here you thought you were looking at simple footprints...).