Category Archives: Planting

Bulbs for All Seasons

In the next few weeks, autumn will arrive and garden centres will fill their shelves with mums, ornamental cabbages and other fall flowers. And spring flowering bulbs will be available too! Spring bulbs like tulips and daffodils are planted in our gardens in the fall and appear the next spring.

There is an upcoming opportunity to learn more about flowering bulbs when Dugald Cameron, former owner of GardenImport, speaks at ‘BULBS FOR ALL SEASONS’ presented by the Peterborough Master Gardeners. Victoria Whitney of Griffins Greenhouses will also speak on spring bulbs. This event happens on Saturday, September 28th at Westdale United Church on Sherbrooke St. It runs from 9 am to 3:30 pm and includes lunch. There will be bulbs for sale as well as a demonstration.

Get your early bird ticket this week by contacting Margaret at 705-876-1771 or mahiggins@sympatico.ca.  [ PMG Bulbs for all Seasons Registration Form .pdf]

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Daylilies: The Perfect Perennial

By Mary-Jane Pilgrim, Master Gardener

Daylilies are popular perennial flowering garden plants. They bloom in our area in July and are often called the ‘perfect perennial’ because of its amazing qualities: showy flowers, wide array of vibrant colors, drought tolerance, ability to grow in most hardiness zones and low care requirements. Daylilies are a remarkable and stunning addition to any garden.

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Witch Stitchery

Daylilies are not true lilies even though their trumpet-like flowers resemble lily flowers. True lilies of the genus Lillium grow from onion-like bulbs, while daylilies grow from a mass of fleshy roots that hold moisture and nutrients. Unlike true lilies, daylily flowers are edible and can be consumed raw or cooked.

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Chicago Heather Marsh

Daylily blooms grow at the end of tall stalks called scapes that can range from 6 to 36 inches long. The genus name, Hemerocallis, is derived from Greek words for beauty and day, referring to the fact that each pretty bloom lasts only one day. Don’t be discouraged though; each daylily flower stalk produces many buds so flowers are produced over a bloom period of several weeks. Many cultivars are reblooming which means that the bloom period for those varieties are extended. There are 20 native species of daylilies and more than 80,000 hybrids.

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Homeward Pilgrim

Because they grow wild in so many places, many people think daylilies are a native North American plant, but they are not. They were introduced to North America by Europeans during the colonial period. Their roots can survive out of the ground for weeks which allowed them to arrive here with the colonists’ ships and spread across the Americas in pioneer wagon trains.

They grow best in zones 4 through 9.  They suffer few pest and disease problems and have a long blooming season. They can be a great solution for areas that are steep or otherwise hard to mow. Their dense root system reduces soil erosion and can choke out most weeds.

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Rocket Booster

In the wild, daylilies occur only in orange or yellow. But since the 1930s, breeders have developed hybrid varieties with flower colors ranging from cream through varied shades of yellow, orange, red, crimson, pink and purple. There are hybrids that have petal edge bands or petal tips or throats of a contrasting color, or with ruffled or scalloped petal edges.

Daylilies will grow for many years without any attention, but the plants will produce more flowers if they are divided about every 5 years or so. This is a job for late summer, after the plants have finished blooming. Dig up the entire plant and place it on a tarp. Cut or pull the clump apart into manageable clumps. Before replanting, use scissors to trim the foliage back to a height of 5 or 6″. When re-planting, daylilies must go into the ground at least 6 weeks before the ground freezes and should be in a location where they get at least six hours of sun daily.

For more information:

Everything You Should Know about Daylilies
All about Daylilies
How to Grow Daylilies

My Favourite Garden Tools

by Emma Murphy, Master Gardener

By day I am a writer and editor, using words, graphics, and design to communicate with my audiences. However, once that working day is over, I have an entirely different set of tools that I use in my garden landscape. What are those “tools of the trade”? Here are my favourites – what are yours?


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A Giant Wheelbarrow 

A good wheelbarrow is worth its weight in gold to a gardener. An essential tool, I use it to transport tools, dirt, mulch, rocks, and garden cuttings from one place to another. For me the most important features are the volume and the wheels. While I have another ‘regular’ one wheel wheelbarrow, this yellow two-wheeled monster is my best friend. I love the stability of the two wheels in my ‘not-flat’ garden. I have had it for so long the bottom plastic has finally cracked from all the big boulders I have dumped into it, but the yellow barrow bottom is now covered with a sheet of metal so it’s still functional. I’ve replaced the original pneumatic (air filled) tires with airless tires. Now I just need to find a new barrow that doesn’t cost more than replacing the entire wheelbarrow! (Special mention to my second favourite wheeled vehicle – an old Radio Flyer red wagon. Acquired from a cousin, this metal workhorse is great for moving plants around, especially in tight spots)

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My Felco #7 Secateurs and Leather Holder

Pruners or secateurs (from the British – a pair of pruning clippers for use with one hand) are indispensable to the serious gardener. There are many brands on the market, but there are two primary types, so it’s important to get the ones that match your needs. Anvil pruners have a blade that pushes the plant material onto a cutting board, whereas bypass pruners have two blades that pass by each other to create a cut. Anvil pruners tend to crush soft plant tissue but, used properly, bypass pruners minimize plant damage. You can read more in Robert Pavlis’ blog on the subject here.

I only use bypass pruners; my Felco #7s are comfortable, light, efficient, and ergonomic. Why Felco? Because they are excellent quality and last forever. There are many models; many friends like the Felco #2s, but there are some designed for left handed people (Felco #9), people with small hands, or people like me that want to minimize hand strain, which is the focus of Felco #7. It provides me with hand and wrist protection, and optimizes the force exerted by the revolving handle. I should probably buy shares in this company. 9a2684c4213171476e13732af3b26537


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A Drain Spade

There are lots of different spades out there, so take the time to find one that works for you. Your height, the weight of the tool, what you need to use it for, and ergonomic considerations should all be taken into account. I have both shovels and spades – shovels tend to have longer handles and a more curved blade than spades – but once I used my drain spade I realized it was going to be my favourite. It’s heavy but I love the long blade for getting deep into the earth, and the narrowness for getting into tight spots. I have actually managed to dig the full taproot of a mature lupin and transplant it (and have it survive) using this spade, and that is an accomplishment in itself.


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Great Gloves

Gloves are a very personal item of clothing for gardeners, but since this is my blog I’ll let you know my favourites are the West County gloves I can get from Lee Valley (the orange ones above) and the Noble Outfitter gloves I just picked up at the TSC Store (the only ones that fit me as I am wearing a finger splint at the moment – that’s a whole other story). Many people like the nitrile and latex gloves, especially for fine gardening work like pruning, but they are too hot for my hands. I am pretty tough on my gloves, so it’s normal for me to go through a few pairs each season.


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My Garden Bandits

What the heck is a Garden Bandit™? Nope, it’s not a robber, just a very handy tool for weeding and clearing areas with minimal hand strain. Its innovative shape, designed after a garden tool used by early settlers, allows you to remove weeds but cutting them off at their roots. It also lets you safely work soil close to existing plants without damaging foliage or tender feeder roots. I got mine from Brenda at the Avant Garden Shop in Peterborough. Made in Canada, the bandit is not sold in big box stores, so contact your local birding/gardening store or nursery to see if they stock them. Check them out here.
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Collapsible Garden Bags

A variation on traditional English ‘tip bags’ and often called kangaroo bags, these lightweight, collapsible bags are great for collecting weeds and waste (and leaves when that time comes). They can be collapsed and stored away easily when not being used, and who doesn’t like space-saving things! I have had several of these bags, but I am not sure where I got these particular ones. They do have them at Lee Valley (or give Google a try). I like them better than the plastic tubs because (well, plastic!), they are lightweight, and I can maneuver them into tight spaces.


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Hori Hori Knife

I was introduced to this tool by my fellow Master Gardeners, and now I understand why it’s a favourite (as you can see I have two of them!). Made in Japan, the hori hori knife is a cross between a knife and a trowel, and can serve multiple functions, including dividing perennials or planting. Traditionally used in Japan to collect specimens for bonsai (hori means “digging”), the knife has a rust-resistant steel blade with a serrated edge on one side and a sharpened edge on the other. About 12 inches overall, it has a hardwood handle and comes with a belt sheath. I have only ever seen these at Lee Valley.


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A Wide Brimmed Hat, Bandanna, Sunscreen, Bug Spray, and Towel

Last but not least the essentials for all gardeners – a nice wide brimmed hat and sunscreen to protect you from the sun’s rays, bug spray (I feel like I am wearing this 24/7 this year!), and a towel to wipe off all that sweat – gardening can be a great workout.

One final hint – you may notice that most of my tools are bright colours. If you – like me – tend to ‘lose’ tools in the garden, or the compost, or the leaf pile, or under a plant, you’ll want to look for tools in nice bright colours so that when your husband turns out the compost in the spring he can say ‘hey honey I found your garden bandit’. That reminds me – I need to put some paint on my hori hori knives!

Happy Gardening! 

Please note: I do not receive any compensation for mentioning where you can get these items

 

 

Spuria Iris

by Mary Jane Parker, Master Gardener

I have always binged on plants. I discover a new plant and then I proceed to find and purchase as many as I can of that plant until I have exhausted myself, and then I move on to something else. Lots and lots of plants.

When iris was my current love, I discovered Spuria Iris.

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Iris spuria “Cinnabar Red”

Spuria iris extend the season of iris well into the summer, blooming here in July. Much used in the cut flower trade for flower arranging, when I first fell in love with them they were difficult to find anywhere in Canada. Originally I ordered from the Midwest U.S. and then Chuck Chapman Iris of Ontario had some available.

Some spurias have flourished for me and some have languished and died. They require full sun, good soil, and warmth. The best patch I have is in a south/east rock garden bed. What really makes the effort worthwhile are the spectacular colours. These hues are not available in any other iris: garnet and gold, vibrant yellows and very different shades of purple and blue. You have to love that!

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Iris spuria “My Gold”

Please note – Because I could not find a good picture of spuria in my garden photos, Chuck Chapman graciously allowed me to use two photos from his website. Thank you Chuck!

For more information and photos of spurias check out some of the links below.

Chapman Iris

Spuria Iris Society

Gardenia on Spuria Irises

Commanche Acres Iris (Missouri)

All about Irises at the RBG

Canadian Iris Society

 

Moisture Tolerant Perennials

by Cheryl Harrison, Master Gardener

So far, spring 2019 has been one of almost continuous rainfall in southern Ontario. The following plants do not demand boggy soil and are hardy in the regular garden. However, they are all moisture tolerant and are a good choice for poolside or boggy plantings.

Lady’s Mantle (Alchemilla mollis) – I love this plant! It looks especially pretty when planted with hostas and bleeding heart…almost a woodland garden without the trees! Lady’s mantle can take sun, sun/part shade and light shade. They can handle dry or very moist soil. They produce frothy, green flowers that look good in fresh, or dried bouquets. Lady’s mantle is one of those plants that acts as a ground cover with its “mantle” of leaves that grow 30-45 cm. (12-15 in.) high. After a rain, the water droplets will bead and sparkle on the fuzzy leaf surfaces.

Bleeding Heart (Lamprocapnos spectabilis formerly Dicentra spectabilis) – Bleeding heart is one of those old-fashioned flowers that was probably in your grandmother’s garden. It grows to about 30-120 cm. (12-47 in.) high. It will keep flowering from spring and into the summer in moist soil. However, it may go dormant, and disappear, if the soil stays dry but will then re-grow again the following spring. Flowers are an unusual shape and may be pink and white or just plain white.

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Lady’s mantle foreground, Bleeding heart background. From the author’s garden.

Joe Pye Weed (Eutrochium purpureum formerly Eupatorium purpureum) – According to one folklore source, this native plant gets it’s name from a colonial-era, indigenous healer named Joe Pye who used the weed to cure fever. This plant grows tall, 100-200 cm (39-78 in) high. With its whorled, lance-shaped leaves and purple flowers, it can be quite an exclamation point in a moist garden.

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Joy Pye weed with visitor.

Creeping Jenny (Lysimachia nummularia) – Creeping jenny is one of those plants that you may grow to hate if it gets loose in an area that provides its ideal growing conditions. I like this plant because it is a great ground cover in the moist garden or as a “spiller” in a patio pot of mixed plants. Its brightly coloured chartreuse leaves will draw your attention to a sun/part shade area of the garden. Creeping jenny spreads by rhizomes and grows very low to the ground at just 5-10 cm. (2-4 In.).

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Creeping jenny in the author’s garden.

Queen-of-the-Prairie (Filipendula rubra) – I only recently discovered this plant when a friend gave me a seedling from her garden. I have it planted along side our pond where it should do well in the moist to wet soil. This plant can be quite spectacular as it may grow to be as much as 245 cm. (8 ft.) high. I am expecting it to have a pale pink, fragrant flower. I can hardly wait!

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photo courtesy of Sugar Creek Gardens 

So, don’t fight mother nature, use plants that can survive and thrive in the moist garden!

For more information Landscape Ontario has a great resource here.

My Five Favourite Perennial Plants

by Emma Murphy, Master Gardener

During the winter months, Ontario gardeners have a number of survival techniques to make it through the “non-green” time of the year (this includes most of Canada, except for those lucky folks on Vancouver Island). We read gardening books, travel elsewhere to see lush green vegetation and flowers, pore over seed catalogues, or surf the web in search of colourful blooms in the Google Image Gallery.

Once spring arrives (still waiting in Central Ontario…) our thoughts turn to getting into our gardens and all the newest plants profiled online, in magazines, and by our favourite garden bloggers. While I love to look at new perennial plants, I thought I would share my five favourite, easy care perennials with all of you, along with the reasons why I love them. I am not a fussy gardener, and I don’t like fussy plants that require a lot of hand holding. To survive in my garden you have to be tough, but that doesn’t mean you can’t be beautiful. I also like my garden to add to the ecological diversity, so I like to plant things that attract pollinators and birds.

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1. Daylilies (Hemerocallis)

Daylilies may be one of the most carefree of all flowering perennials. They grow quickly and live for a long time (looking nice even when not in bloom). They thrive in almost any soil, will grow in sun or shade, and don’t seem to be troubled by insect pests or disease. Known for being tough, they dazzle us with their big, colourful flowers in all shapes and sizes. Blooms begin in midsummer and continue into early fall. The best part? New blooms every day. Daylilies combine well with other perennials like coneflowers (Echinacea), bee balm (Monarda), and summer phlox (Phlox paniculata). For me they are a mainstay in the garden, and I can share with friends, dividing as my clumps get big.

 

2.  Blanket Flower (Gaillardia)

One of those flowers where I actually think the Latin name is prettier than the common name. It’s another summer and fall perennial that blooms right until the first frosts, providing a late season burst of colour in your garden. Part of the sunflower family (Asteraceae) and native to North and South America, blanket flowers come in a range of colours (yellows/reds/oranges), although I find that the tried and true Gaillardia x grandiflora is my favourite. These are not the longest lived perennials, but reproduce well so I have never had an issue with them dying out. They are easily divided, can handle poor soil, and will bloom continuously, although I find deadheading does extend their blooming (something to do while you drink your coffee or tea and wander around your garden in the morning).

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3. Purple Coneflower (Echinacea)

I agree with many other that no garden should be without this tough native flowering plant with large, purplish pink flowers. The common name derives from the prominent cones in the center of a single layer of slightly reflexed petals. These plants are wonderful summer bloomers, providing food for butterflies, bees, and other pollinators. I love them in the fall and winter too, as I leave them up in the garden and wonder at the finches that land on them and hungrily eat the seedheads. All parts of the plant have medicinal properties and you often see it in natural cold and flu remedies.

Native Echinacea only comes in purple, pale purple, or yellow, but hybridized echinacea (derived from E. purpurea)  can be red, orange, pink, and green. While there are lots of new hybrids out there now with different colours and shapes I am still partial to the tried and true varieties, although I confess to liking Echinacea ‘Merlot’ with its reddish stems. Read more here about which one to choose (true natives vs hybrids) and why. Coneflowers can propagated by root or clump divisions. This year I am on a search for our native Echinacea pallida, which has thinner reflexed petals and a pale purple hue.

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4. Asters (Astereae)

Aster comes from the old Greek word ‘astér’ which means ‘star’ and refers to the shape of the flower. These lovely delicate daisy-like flowers come in all shades of pink, purple, lavender, and white. Flowering from early summer to fall (depending on variety), they can be started from seeds, but purchasing young plants is the best option. Plant them out in spring for summer blooming that usually extends to fall. Asters do well in full and partial sun conditions but like good soil and drainage for best show. I love the combination of fall asters and goldenrod in the late summer and fall in my garden – so much colour and texture! There are so many asters – you can learn more about this fascinating group of plants here (for Ontario) and also here.

5. Black-eyed Susans (Rudbeckia)

What can I say? I LOVE the Rudbeckia family of flowers. With lovely bright yellow petals and contrasting centres, these plants demand attention. Rudbeckias in general are perennial, but the smaller Rudbeckia hirta can be grown as an annual if started early enough. In most zones they start flowering from early summer and continue on until fall. The ‘Goldsturm’ black-eyed susan (Rudbeckia fulgida ‘Goldsturm’) is considered to be among the best perennials of all time (Perennial Plant of the Year in 1999), bringing a bursts of colour from late summer into October. These drought-tolerant plants can grow about two-feet tall and offer the best visual effect when planted en masse. A shorter variety Rudbeckia fulgida var. sullivantii ‘Little Goldstar‘ – grows to just knee height if that is more to your liking. Rudbeckia hirta ‘Irish Eyes’ and ‘Indian Summer’ are also popular.

My two favourites are the butterfly magnet Rudbeckia triloba and Rudbeckia laciniata ‘Hortensia’, commonly called the Outhouse Plant. The first (triloba) is an excellent native addition to naturalized areas, wildflower meadows, prairies, cottage gardens, native plant gardens and borders. Plants form a rosette of green leaves the first year, then the second year they produce bushy, upright stems loaded with thousands of tiny brown-eyed golden daisies from midsummer on. As a self-seeding biennial, it is ideal for naturalizing. The Outhouse Plant is an old heirloom selection – very tall, with many fluffy double chrome-yellow daisies on the top. It’s not a bad idea to pinch these down in June to get them to be bushier, as they tend to flop in the windy summer thunderstorms. Be warned – this one can be a vigorous spreader, so keep on top of it!

 

 

 

GreenUP Ecology Park Spring Sale

By Suzanne Seryck, Master Gardener

GreenUP Ecology Park Spring Sale – Saturday May 18th 2019

The GreenUP Ecology Park  has often been called a hidden gem, it has been in Peterborough in its current location for 25 years, but many people are still unaware of its existence. I first discovered the park approximately 8 years ago when I was researching native plants. At that time I wanted to plant a large perennial bed filled exclusively with native plants. I spent all winter researching the plants I wanted and where I could buy them locally and came across the Ecology Park and better still discovered they were holding a spring sale.

I dutifully arrived on the day of the sale 5 minutes after opening only to discover a very, very long line of people all carrying totes, boxes, bags, anything that could be used to carry plants. Even though it was incredible busy I was able to find almost everything on my list with help from the many knowledgeable volunteers and staff that were on hand to help. I was quickly and efficiently processed through the payment line, and was soon on my way home to start planting. The quality and choice of plants was extensive, and I knew then that I had found something special. I have been returning to the Ecology Park every year since either as a customer or as a volunteer.

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Native plants are plants that grow locally in a particular area. Whether you are planting an entire garden of native plants or simply planting one or two, the benefits are numerous. Native plants tends to be more hardy to the local conditions, needing less watering, and next to no pesticides or fertilizers. They can improve air quality, help in managing rain water runoff and maintain healthy soil as their root systems are deep and help prevent soil from compaction and erosion. Native plants provide both habitat and food sources for wildlife, as many native pollinators rely on native plants. There are numerous interesting articles on the internet detailing the benefits of planting with native plants – I have listed a few below. There are also links to two other native plant nurseries (in addition to Ecology Park).

Why Native Plants Matter
Benefits of Native Plants
List of Native Plants in Ontario
(from Ontario Wildflowers – a comprehensive list)

Native Plants in Claremont
Ontario Native Plants (online only – ship from Hamilton)

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This year the GreenUP Ecology Park Spring Sale is being held on Saturday May 18th from 10 am until 4 pm. As well as trees, shrubs and wildflowers you can also buy vegetables and annuals at the sale along with compost, mulch and wood chips, but make sure you bring your own containers to hold the compost or mulch. A list of available trees, shrubs, wildflowers and grasses is available on the Ecology Park website.

Children are welcome, even encouraged. While you shop there is a large children’s play area complete with a willow trail and cedar maze to keep them entertained. Be sure to check out the latest addition to the park, the new children’s education shelter which has been built using sustainable practices.

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And finally, the Peterborough Master Gardeners will be on hand wearing their red aprons between 10 am and 2 pm to answer any gardening questions you might have. Be sure to stop by and say hello!

Spring Cleaning Your Gardens

by Cheryl Harrison, Master Gardener

It is that time of year again…..time to start to prepare your gardens and lawn for the outdoor living season.

It may be too early yet to walk on your lawn, it should be firm not mushy with moisture, or in your gardens, the soil should be crumbly and not stick together. I know that it is still very early but there are a few things that you can do.

I have started to cut back the ornamental perennial grasses. These grasses begin to grow early. They like cool weather so they need to be cut back in preparation for this early growth garden.

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I have also begun to remove some of the debris around the edges of my perennial gardens. I avoid walking in the gardens because they are still quite wet and partially frozen in some cases. We also have a small pond that I have been able to cut back the cattails. I will not get to carried away with this yet because there are some “critters” that live in the garden clutter that I do not want to disturb. For example, ladybugs will still be snoozing. You also do not want to accidentally discard a praying mantis egg case. Both insects are beneficial insects because they are predators and will eat other less beneficial insects in your garden.

My garden shed was opened this weekend. I have started to move out my rain water collection barrels and to put them in place.

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It is a great time to inspect your trees and shrubs before they leaf out. Remove any winter injured growth and any growth that does not keep the plant balanced or where branches rub together. There are some flowering shrubs that, if you prune now, you may remove this year’s flower buds so know what you are dealing with before you prune.

It is also not to late to do some planning. You will soon be able to see what survived the icy Ontario winter and what did not. You can think about what you would like to plant in the place of those that did not survive. Always remember to think about your plant zone, amount of light, moisture requirements and the type of soil when choosing a new plant. Matching a plant to the growing conditions is the best way to grow a plant that has a chance to thrive and overwinter successfully.

There is lots more to do but it is still early spring! Stay focused and finish one task at a time and your garden will be outdoor living ready before you know it.

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The Peterborough Garden Show

By Mary-Jane Pilgrim, Master Gardener

It’s coming in 25 days.  It can’t come soon enough.  In our city, “The Garden Show” is a true sign of spring.  It’s an occasion that brings together speakers, workshop leaders, vendors, horticultural society members, master gardeners, exhibitors and many others for one reason:  “For the Love of Gardening”.PGS-logo-small

This year marks the 19th fantastic show: 
April 26 – 28, 2019 (Friday 5-9pm, Saturday 10am-5pm & Sunday 10am-4pm).

And there’s great news ! The show has MOVED – to Fleming College’s brand new Trades and Technology Centre on Brealey Drive with lots of FREE parking and a $10, one-price ticket so you can enjoy the show all weekend.

The Peterborough and Area Master Gardeners will have a booth at the show, and will be happy to answer any gardening questions that you may have. Watch for our red aprons!

The theme “Coming Up Roses” is reflected in several of the amazing speakers along with educational and fun workshops and demos.

This award-winning show was honoured in 2017 with both a “Canada 150 Garden Experience”, and “Garden Event of the Year” by the Canadian Garden Council, so come and see what all the fuss is about.

You will find many of your old favourite vendors along with some new ones.

…and don’t forget the popular “Little Green Thumbs” Children’s Garden that is always teaming with liveliness and action! There are learning activities, face painting, crafts and even a take-home project. Their theme this year is “Miniature Gardens for Elves and Fairies”.

All the show profits go back into our community to fund scholarships for post-secondary students studying in horticulture-related fields,various local projects & Community Gardens.  Since 2002, the show has put over $200,000 back into our community.

Please save the date, visit and and learn why “Everything’s Coming Up Roses” in 2019.

Learn more about the incredible speakers, workshops, bus trips, places to stay and tickets here: peterboroughgardenshow.com.

 

Truth or Fiction? Are Black Walnuts Toxic in my Garden?

by Emma Murphy, Master Gardener

As a Master Gardener, one of the most common questions I get asked is about the toxicity of walnut trees (Juglans nigra).

“Well I heard that the juglone stuff in the roots kills everything and that I can’t plant anything under or anywhere near a walnut tree.”

Well yes Virginia, you can plant a garden under a walnut tree, and have it thrive. Let’s look at Exhibit 1 below – an established perennial bed under a walnut tree. It’s at our house, so I guarantee it’s real, and it’s been there since late 2007.

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Lots of lovely perennials here – hostas (Hosta spp.), daylilies (Hemerocallis), bearded iris (Iris germanica), summer phlox (Phlox paniculata), wild ginger (Asarum canadense), purple coneflower (Echinacea purpurea), ditch lilies (Hemerocallis fulva), although those last ones are doing just a little too well LOL. Don’t believe it’s a walnut tree? Here’s a photo from a bit further back on the street.

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Yes, she’s a big old lady – we think she was planted around the same time the house was built, making her about 140 years old. I think she’s getting a bit tired out – most years she doesn’t produce too many walnuts. Her slightly younger cousin is to the left of the barn in the background – LOTS of walnuts off her (and yes a garden under that one too).

So where does this fallacy come from that ‘nothing grows under a walnut’? Well certainly all parts of the walnut tree contain a chemical called juglone (heck it’s even in the Latin name!). Juglone is a chemical that affects other plants growing nearby (a phenomenon called allelopathy). Simply put, allelopathy involves “living or dead plant parts that release chemicals into the soil which have an effect on other plants—positive or negative.” For walnuts it seems like an attempt at self preservation, with juglone acting like a natural herbicide on other plants.

As Professor Linda Chalker-Scott explains in her recent (2019) peer-reviewed Washington State University Extension paper, damage to tomatoes and other crops near walnut trees in the 1920s caused people to believe that toxic chemicals were involved, and this perception persisted and became widespread despite there being no evidence (and this was before social media existed!). The US Department of Agriculture did field testing – no problems. When applied in a laboratory setting to seeds and seedlings it did cause stunting, wilting, and necrosis, but the specific way it did this was unclear. The most recent science suggests that juglone disrupts photosynthetic and respiratory pathways and interferes with water uptake in plants.

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So! It does affect plants – the laboratory says so. Well yes, and no. Field tests do not support the laboratory work, which doesn’t accurately mimic real life conditions in your average residential garden (again, for more detail read the excellent paper referenced above). Two very old University Extension papers (1973 and 1993) continue to be used to state which plants are ‘sensitive’ and which are ‘tolerant’. However these were simply observational papers—meaning that they correlate the presence of walnut trees with damage to other species but do not confirm a causative relationship. Neither should be considered good scientific evidence.

Gardening With Walnut Trees – My Story

I am sure the scientists, arboretums, farmers, and garden writers will continue to debate this topic for a while. Meanwhile, here’s our story. In 2007 I wanted a garden bed under our black walnut in my front yard. At the time I had heard the walnut horror stories, so I thought – well, how about I just don’t disturb the roots of the tree? (not a good thing to do when establishing any garden beds under a tree). I put good topsoil and compost down, making sure to minimize tearing up of the soil and roots, and planted, and watered, and waited. Things grew. Winter happened. Next spring plants came up. For the most part I just moved perennials that were already on site, although some hostas were new. Here’s the garden in 2008 in the fall.

BP5_plants_2008

Fall asters (Astereae spp.), sedums (Sedum ‘Autumn Joy’ in this case), hostas (Hosta spp.), wild ginger (Asarum canadense), fall rudbeckias (Rudbeckia fulgida and triloba), purple coneflower (Echinacea purpurea), ninebark (Physocarpus opulifolius), iris (Iris spp.), astilbe (Astilbe spp.), sweet woodruff (Galium odoratum), Ozark sundrops (Oenothera macrocarpa), coral bells (Heuchera spp.), cranesbill (Geranium spp.). All doing just fine.

And 2009 below, in the spring. Irises (Iris spp.) lemon lilies (Hemerocallis lilioasphodelus), lungwort (Pulmonaria spp.), poppies (Papaver rhoeas), ditch lilies (Hemerocallis fulva), variegated solomon’s seal (Polygonatum odoratum ‘Variegatum’), bracken (Pteridium aquilinum), bleeding hearts (Dicentra spectabilis), daylilies (Hemerocallis spp.).

BP6_plants_2009

Certainly, planting in general under walnuts is challenging – they cast dense shade and have extensive, water hungry root systems. Watering after establishment and for the first season is critical. We also had our walnut tree pruned professionally (it needed it) so it actually gets decent sunlight in the latter part of the afternoon. Like any fruit or nut tree they are messy, from their spring pollen to their leaves and nuts…oh those nuts.. 2017 was a crazy year – buckets of walnuts (I even had to engage my neighbours’ lovely children from across the street to help collect them) to 2018, with almost no walnuts. My trees are old too – although well pruned, their leaves drop at that first hard frost. 1

 

In Defence of Walnut Trees

Black walnuts are not all bad, and I will continue to treasure them in my yard. They are an amazing shade tree, are highly valued for their fine grained dark wood (for furniture), a great food source for wildlife and birds, and my white breasted nuthatches’ favourite spot to hide their seeds.

We have definitely had our challenges with our walnut trees, and I’ve learned a great deal over the past 20 years. But one thing I know – I can garden with them around. You can too.

Note: Black walnuts are not the only tree that produce juglone – other members of the Juglandaceae also produce it as well as hickory trees. Butternut, English walnut, bitternut hickory, pignut hickory, pecan, shagbark hickory, mockernut hickory are in the same family.