Pruning

Temper your Enthusiasm

(Originally posted September 15, 2019)

The crisp nights and cooler days have arrived- a sure sign that fall is around the corner. Fall is generally a time of yard work and many people become very enthusiastic to tackle outdoor chores- even people with no interest in their yard whatsoever throughout the rest of the year tend to catch the ‘gardening bug’ during the autumn months. Often this enthusiasm is directed at whacking back various trees and shrubs in their yard. While there is certainly lots to do before the snow flies, pruning is the one task that we want to minimize at this time of year. (Sorry Edward Scissorhands wannabes!)

Let’s start with the effect that pruning has on a tree or shrub… it promotes new growth. New growth is tender and needs time to toughen up to the environmental conditions around it. At this time of year, our frosty mornings are just around the corner. If we prune now, new growth that emerges will not have the time to properly harden off before the cold weather hits, which can ultimately lead to death of the new plant tissue… therefore you will get dieback. On deciduous trees and shrubs (ones that lose their leaves for the winter), this dieback would be apparent in the spring; on evergreens it could become obvious during the fall and winter months. Dead new growth is not the nicest thing to look at on a plant that is supposed to stay green for the winter!

Furthermore, plants are using this time to start shutting themselves down for the winter. They are gathering sugars and carbohydrates from their leaves and storing them in their stems, trunks and root systems; valuable energy to help the plant survive the winter and flush out new growth in the spring. Removing the leaves before they fall doesn’t allow the plant to relocate these sugars to their ‘winter storage facilities’ and therefore the plant is robbed of it’s energy sources for the months ahead. Additionally, the stimulation of new growth through pruning counters what the plant is trying to do. Instead of putting energy towards properly ‘shutting down’ it is putting energy towards new growth; this can weaken the plant going into the winter.

While it is true that plants can rebound from a late season prune, it is not an ideal time for this gardening task.

So… if you feel the call of the pruning saw, hedge shear or lopper- ignore it! Opt to warm up some apple cider, mosey through the garden, and start your ‘to do list’ for next year. Those shrubs and trees that you are just dying to hack back now will still be there in the spring and they can be first on your ‘hit list’ for a dormant season prune come a mild day in March***! Not to mention, with all that energy [properly] saved-up for a spring flush, the plant will be able to quickly rebound from your ‘haircut’.

Can you hear that?

That is the sound of your shrubs and trees breathing a huge sigh of relief.


***While any plant can be pruned in the dormant season, it is important to note that if you prune anything that flowers early in the growing season, you would most likely be removing flower buds. For these plants it means that a hard prune = no flowers for the upcoming growing season. While some people may gasp in horror at the thought of this, sometimes it is a necessary evil in order to renovate an overgrown shrub. More on pruning and timing of pruning in future posts… I promise!

Remember these early season beauties? A prune at this point in the year (or any time leading up to their flowering period) would remove their flower buds. Believe it or not, plants such as these are already prepared for their 2020 show!

Clockwise from top left: lilac (Syringa sp.), serviceberry (Amelanchier sp.) magnolia (Magnolia sp.), Dogwood (Cornus sp.)

Deadheading Technique #2: The Haircut

(Originally posted: July 27, 2019)

We are still in the thick of summer deadheading- the constant attempt to tidy perennials, prolong their bloom or encourage a repeat bloom (depending on the perennial). If you like non-precise gardening tasks, this type of deadheading is for you! I call it ‘the haircut’ but it is also called shearing.

Remember our catmint (Nepeta) friends?

Well here are the three amigos again; one plant has already been sheared (a week prior to taking this photo), and two are still waiting in the foyer, reading their magazines, patiently waiting for the hairstylist (me)… who is taking her sweet time in completing the task!

I am going to keep this super easy: this deadheading technique involves grabbing a handful of stems and cutting them shorter. If there is new growth emerging from the base of the plant, you will want to avoid cutting this growth- it will be responsible for rejuvenating your plant! Once everything has been cut back, you can shape the clump if you wish. It really doesn’t get simpler than that! You can use secateurs for this task or hedge shears. I find hedge shears make a much bigger mess that requires cleaning (unless a drop sheet is put down first… something that I am known to do). I also find that I have much less control over the finished product with hedge shears so secateurs are certainly my ‘go to’ for this type of work.

Back to the task at hand…

Here are a couple photos of the finished ‘catmint project’. If you are thinking that the newly sheared plants look horrible, you would be correct. With that said, all you have to do is look at the middle plant to see how much better the plants will look in one short week. Also note how the clumps have been shaped to be slightly ‘dome-shaped’. I do this because I find it looks tidier overall.

Let’s do one more example of shearing… this time it is Geranium getting the haircut. In this case, the new growth coming up from the centre is left untouched- with this new growth, the plants will fill-in in no time!

If this method of ‘whacking things back’ is a little too crude for your liking, you can always cut each stem individually to a point just above a leaf (also called a node). It is from this point that the plant will branch and send out new growth. I tend to do this for Salvia spp. so that I don’t end up with unsightly ‘chopped-up’ leaves that are left on the plant; for larger-leaved perennials like Salvia, I find that looks especially bad! This plant tends to reach a point in the growing season where the removal of spent flowers to lateral flower buds (next post!) starts to make the plant look funny. Taking down the stems helps provide a reset.

Here are some common perennials that can be sheared:

  • Cranesbill (Geranium spp).- the ones that get long and sprawling after flowering; spreading/dwarf varieties do not get sheared. If your Geranium is rambling over-top of other perennials, it is eligible to be sheared!

  • Oriental poppy (Papaver orientalis)- cut to the ground including foliage

  • Thread-leaf tickseed (Coreopsis verticillata)- when there are more spent flowers clinging to the plant than nice ones, it is time to give the plant a light shearing

  • Spurge (Euphorbia spp.)- CAUTION! The milky sap that comes from the cut ends of this plant is an irritant to skin and eyes. Be sure to wear gloves, long sleeves, and eye protection. Euphorbias also harmful if eaten.

  • Lavender (Lavandula spp.)

  • Artemesia spp.

So there you have it! Quite possibly the simplest gardening task that can really clean-up the look of your perennials. Get out those hedge shears or secateurs and let the make-overs begin!

Deadheading Technique #1: Leave no Evidence!

(Originally posted: July 19, 2019)

Well the time has come for daylilies (Hemerocallis spp.) to shine…blooms of all sorts of colours rising above their grassy foliage. Then, just as quickly as they begin to shine, they start to ‘un-shine’ (if this is not a word, I would like to propose it as a new one). Afterall, Hemerocallis translates to ‘beautiful for a day’. These perennials look SO MUCH better when they are deadheaded to the point that, when I walk by a property with daylilies that haven’t been deadheaded, it takes everything in me to not pull out some pruners and get to work. I’ve even gone through the conversation in my head:

Hey! What are you doing?!’

Your daylilies don’t look very pretty and they are begging to be tidied up. Plus this is free labour!

I don’t really care. Get off my property and please don’t come back.

OK. Sorry.’ (Said while thinking: ‘you really should care because they really don’t look very good’)

…as the inner dialogue never ends up with a positive outcome, I decide not to trespass.

Now that we established that your daylilies will likely NOT be miraculously tidied by a crazy gardener, it means you should learn the techniques so you can do the work yourself!

There are a few steps to tidying daylilies. The first step is done during the bloom period. Old withered flowers are removed, as are the seed capsules. Be careful not to confuse the seed pods with flower buds. In general, seed pods are more roundish and flower buds are elongated. Once you have identified the parts to be removed, tidying the plant is easy! The withered flowers and seed pods simply snap off by hand.

A daylily with lots of flower buds and a seed pod (circled in red).

Once the last flower has faded from a particular flower stalk we move on to the next step of tidying up the plant. This is perhaps the easiest deadheading technique which I term the ‘leave no evidence’ approach, otherwise known as cutting back the whole flower stem. Essentially you are removing the entire stem to a point below the foliage- removing all evidence that the plant ever had flowers. It is a technique used for daylilies, hosta, iris, coral bells, scabiosa among others.

A before and after look at a hosta in need of deadheading. The photo on the right is of a hosta breathing a sigh of relief that it’s unsightly spent flowers have been removed… or maybe that was my sigh of relief.

So have a look at your garden- if you see any of these common landscape plants with spent flowers still clinging to them, do your plants a favour and give them a little facelift… with some simple deadheading!