Two Plants that Never Stop Giving

By Sharleen Pratt, Master Gardener

My Mom passed away last October at the age of 97 during a difficult period of the pandemic.  A dear friend gifted me a miniature rose plant that is a beautiful coral pink.  My parents were from Ireland and they always grew roses in their garden.  I adore the flowers but have never been a huge fan because of the many common diseases they get such as powdery mildew, rust and block spot.  Also, it seems that every time I am near a bush, the thorns love to grab me and wreak havoc on my skin!

Close-up of the Coral Pink Rose!  November 2021 in Author’s Garden

However, this rose was special and I managed to keep it alive during the winter months and after all signs of frost, I planted it in my front garden, tucked amongst other annuals such as the Impatiens walleriana ‘Variegata’, common name Variegated Impatiens.  This plant belonged to Norma Evans, a well-known founding member of the Peterborough Master Gardeners as well as a member of both the Peterborough and Omemee Horticultural Societies.  She passed away in 2017 at the age of 90.  Through cuttings, this gorgeous plant that is a perennial in warmer climates, has been passed amongst many friends and family.

Rose beside the Impatiens, October 2021, Author’s Garden

I was gob smacked by how well that little rose and that one small cutting of the variegated impatiens performed in my garden this summer.  The rose was blooming well into November.  The impatiens succumbed to the frost on November 4th, however, it was as large as a small bush.  It also had lovely deep pink flowers all summer long.

The Rose continues to bloom! Author’s Garden, November 2021

I have two cuttings of the impatiens growing in my kitchen window so that this plant can continue to be grown year after year.  As for the rose, I have heaped it with lots of leaves and soil in the hopes that it survives our Peterborough winter.

My Mom and Norma would be smiling and I believe they both have had an invisible hand in the success of these plants.  I know they have brought me peace and happiness. Memories are what we hold on to, and what better way to honour a person’s life than through the growth of a plant!

Happy holidays!  I hope you have all been able to safely celebrate Christmas with a few loved ones. Wishing you all the best in 2022.

Deck the Halls with Boughs of Holly

By Mary-Jane Pilgrim, Master Gardener

Common European holly (Ilex aquifolium) has a long history of use as a Christmas symbol. It appears on Christmas cards, in holiday arrangements, in Christmas carols, and my personal favourite: in stained glass ornaments. This shiny, spikey evergreen plant is easy to use for decorating, plus it has a long history of cultural significance.

Holly is a shrub-like tree that can grow up to 10-15 feet in height. Its leaves are thick and leathery, with serrated edges and spiky points. The female versions of the tree produce the red berries we’re so used to seeing everywhere at Christmastime. It is sold as a perennial in our region, but very few of the over 400 species are actually hardy in zone 5 (Peterborough). One such variety is American holly (Ilex opaca). The plant requires four or more hours of direct, unfiltered sunshine per day, and requires acidic, rich, and well-drained soil.

For centuries this magical shrub-tree has been been used in winter solstice decorating in central and northern Europe, specifically among the Celts who wore crowns of holly for good luck. They would hang holly sprigs from their windows and doorways to keep evil spirits away. Holly gradually became a symbol of hospitality and welcome.

In pre-Victorian times Christmas trees were not pines, but holly bushes. Christian culture adopted the holly – along with ivy – in Christmas celebrations; holly symbolized Christ’s crown of thorns; the crimson berries represented His blood and the evergreen a metaphor for life after death.

Holly is a real showstopper in winter when little else is green. The same features that make it so attractive today are what made holly a mythical plant to ancient cultures.

Holly’s red berries, toxic to humans and most household pets, are only produced on female plants. Hollies are dioecious, which means male and female flowers occur on separate plants (female flowers must be pollinated by male flowers to produce berries). So if you would like to see those bright red holly berries in winter, you’ll have to plant one male for every 5-10 female plants. The berries are a food source for some of our native birds in the winter.

While most of us no longer believe in the magic of plants, holly is indeed a beautiful adornment for our winter homes (“deck the halls with boughs of holly”), and has a long history of significance throughout the world.

From the Peterborough Master Gardeners to each of our amazing subscribers, we’d like to wish you all a blessed Christmas & holiday season!

Resources

Houseplant Facts and Fictions

By Laura Gardner, Master Gardener in Training

We turn to searching for information online or in books on how to care for our plants. Unfortunately there are a lot of inaccuracies surrounding certain beliefs and practices concerning them. Since most of our attention is now focused on indoor gardening, let’s look at five questions concerning houseplants.

1. Are Poinsettias Poisonous?

You may have been gifted with a Poinsettia (Euphorbia pulcherrima) and you may be concerned because you have heard that they are poisonous. The plant, while not edible, would need to be consumed in large quantities to be harmful. That being said, it still is wise to keep the plants out of reach of pets and children as some consumption may lead to digestive distress. Like other members of the Euphorbiaceae family, Poinsettias produce a milky sap and so handling the plant without gloves may affect those with a latex allergy.1

2. Can Houseplants Filter or Absorb Pollutants?

Recently I read in a book on houseplant care that plants draw in harmful volatile organic compounds (VOCs) such as formaldehyde and benzene and clean the air for us. Two examples mentioned included the Peace Lily (Spathiphyllum) and the Spider plant (Chlorophytum comosum). It stated that the former can filter out formaldehyde and the latter both formaldehyde and benzene. While it is true that plants have the ability to absorb pollutants, large numbers are required to have a significant impact. The belief that plants clean the air may be associated with a single NASA study2 from the 1980s that was conducted in an air-controlled laboratory setting and not in an open home or office setting. More recent research has determined that a building’s air handling system or open windows is more effective at reducing pollutants than plants. One would require 10-1000 plants per square meter in order to be comparable.3

3. Will Misting and Pebble Trays Increase Humidity?

We may struggle with maintaining optimum humidity levels in the winter for our tropical houseplants. Many books and online sources recommend increasing relative humidity around plants through misting and placing the plant pots on trays filled with pebbles and water. Misting is generally ineffective because the water evaporates so quickly. It would have to be done constantly to have an impact. Concerning pebble trays, an experiment published in the American Orchid Society Bulletin found that in the winter (set in a home in Minnesota), relative humidity levels were raised only slightly. The RH at 40 mm above the tray was measured at 3%; at 110 mm 2%; and at 300 mm it measured 0%.4 Using a humidifier is really the only method that has the ability to increase humidity levels significantly.

4. Should you Use Ice Cubes for Watering Orchids?

Recently I read a comment on the Master Gardeners of Ontario Facebook site that someone said that their Moth Orchid (Phalaenopsis) came with a tag advising them to use ice cubes as a method of watering it. It seems that this advice is really intended to help prevent new Orchid owners from overwatering their plants. While there is a study that found that using ice cubes did not negatively affect the health of the orchids, it was only conducted for a period of 4-6 months. A problem with using ice cubes is that it has the potential to accumulate salt build-up (from water and fertilizer) that can affect the plant’s longevity in the long term.5

5. Should you use Leaf Shining Products or Oils?

Some sources advise using commercial shine products or oils to help make a plant’s leaves shiny and reduce build-up of dust. However, there is research indicating that the use of leaf shine on Weeping Fig (Ficus benjamina) caused the plants to have a reduced tolerance to low light stress, resulting in three times as much leaf loss as untreated plants.Treated plants required higher light levels.6 Another problem is that they can block the pores or stomata in the leaves of some plants, resulting in reducing the plant’s ability to photosynthesize and respire.

Here are three easy to care for houseplants:
Schefflera, Aloe Vera, and Epipremnum aureum (Pothos)

References

  1. Newman, S.E. and B.E. Edmunds. Poinsettias. Colorado State University Extension. Online: https://extension.colostate.edu/topic-areas/yard-garden/poinsettias-7-412
  2. Wolverton, B.C. et al. Interior Landscape Plants for Indoor Air Pollution Abatement. Online: https://ntrs.nasa.gov/citations/19930073077
  3. Cummings, Bryan E. and Michael S. Waring. Potted plants do not improve indoor air quality: a review and analysis of reported VOC removal efficiencies. Journal of Exposure Science & Environmental Epidemiology. Volume 30, pp. 253–261 (2020). Online: https://www.nature.com/articles/s41370-019-0175-9
  4. Kohl, Douglas. A Study in Humidity: Douglas Kohl Evaluates the Effectiveness of a Common Method to Raise Humidity around Orchids Growing in the Home. American Orchid Society Bulletin, 63(8). 1994. pp. 916-917.
  5. American Orchid Society. Greenhouse Chat Webinar. June 2021. Online: https://www.aos.org/All-About-Orchids/Webinars/chat/Greenhouse-Chat-June-2021.aspx
  6. Steinkamp, K. et al. Acclimatization of Ficus benjamina: A Review. Online: https://mrec.ifas.ufl.edu/foliage/resrpts/rh_91_5.htm

Winter Favourites

By Lois Scott, Master Gardener

As I begin to hunker down for winter, the garden outside my windows still gives me pleasure.  Some plants are blackened and not particularly attractive but grasses continue to look beautiful throughout the winter months. 

Two of my favourite grasses for winter are Little Bluestem (Schizachyrium scoparium) and Switchgrass (Panicum virgatum).  These are both native grasses that are not only beautiful but well behaved in my garden.  Little Bluestem is a great choice for a dry, sunny spot or even a rain garden that may flood and then dry out.  It can grow up to 4 feet high and 2 feet wide. Switchgrass is a taller grass that grows to 6 feet with a 3-foot spread.  It prefers soil that is medium to wet and is also a great choice for rain gardens. 

Bluestem in author’s garden

Both these grasses are host plants for many species of butterflies.  They also provide seeds and nesting materials for birds and shelter for small mammals.

Switchgrass in author’s garden

Little Bluestem and Switchgrass are “warm season” grasses which means that unlike “cool season” grasses they don’t go dormant in the heat of summer.  Warm season grasses thrive in the heat.  They start growing later in springtime and flower later in the summer. 

This brings me to why I love them in winter.  They hold up their beautiful seed heads that look stunning when frosty, they create movement in the garden, provide colour all winter long and they help make my garden a winter refuge.

Resource:

https://www.inournature.ca/native-grasses-for-ontario-gardens

The Plastic Dilemma

By Marilyn Homewood, Master Gardener

The recent severe weather experienced by the west coast drives home the reality of our changing climate. Gardeners pride themselves on being good stewards of the land and are always trying new techniques to improve. However, there is a fly in the sustainability ointment.

The horticultural industry uses a lot of plastic. Pots, weed barrier, netting, propagation equipment; it’s overwhelming.  On a global basis, about 4 percent of world oil production is used as a feedstock for all plastic and another 4 percent is consumed as energy in the manufacturing process. Emissions are just the beginning of the problem.  The Earthways Center at the Missouri Botanical Garden estimates that about 350,000 lbs. of horticultural plastic enters the waste stream each year in America. Plastic is ubiquitous, does not degrade rather it disintegrates and some types (PVC and polystyrene) leech toxins into the soil and groundwater.  As it disintegrates, it becomes microplastic fragments that can be found both in marine settings and in the soil.  We are all aware of the impact on marine life but it has now been discovered that these fragments are in the soil and have a significant negative impact on arthropods and roundworms (all important in the breakdown of organic matter). 

Freedom from plastic is the goal but will take time. There are things gardeners can do right now to reduce their plastic consumption.

  • Extend the life of plastic you already own by careful handling and reuse
  • Forgo plastic when workable alternatives exist. Use biodegradable pots made of coir or fibre and try soil blocking for starting seedlings. Use wooden plant markers.
  • Buy bare root plants and or start plants from seeds to cut down on plastic pots
  • Use planters made of terra cotta, metal or ceramics.
  • Only use tools made from metal and wood
  • Skip the use of bagged products and purchase these products at a bulk outlet using preowned containers.
  • Use weed barriers that biodegrade such as cardboard or biofilm (made from corn)
Metal tools that last a lifetime

There may still be items for which no good alternative exists in your situation.  In these cases, purchase higher quality versions that are more durable and last a long time.  Companies such as Bootstrapped Farmer are now specializing in this type of product.

Many years ago (1996) I purchased 2 large plant trays from Lee Valley Tools and am still using them.  The trays are still in the catalogue and I am going to purchase more.  I have a metal watering can which I have had since I started to garden.  These things can be passed along to younger gardeners.  As the urgency of this issue becomes apparent, additional products come to market assisting in the transition to freedom from plastic.

“We have forgotten how to be good guests, how to walk lightly on the earth as its other creatures do.” ~ Barbara Ward


Resources

https://www.gardenorganic.org.uk/say-no-plastic-garden

https://www.npr.org/2019/07/09/735848489/plastic-has-a-big-carbon-footprint-but-that-isnt-the-whole-story

https://www.bootstrapfarmer.com/

Mushrooms in the Wild

By Mary-Jane Pilgrim, Master Gardener

Go for a hike in the woods in November, and you’ll see plants you’ve probably never seen before. With the wetness of fall comes an entire forest of miniature fungus elements of many different shapes, sizes and colours. Some can be eaten, others don’t taste very good, some will make you sick and a small number of them will kill you. In general, the types of trees in the forest will determine what fungus and hence what mushrooms will grow there.

Mushrooms are the fleshy, spore-bearing fruit of various fungi. They are generally short-lived. They can emerge from the ground, expand, produce spores, and die back in a matter of a few days. Some are as big as dinner plates and some as small as pinheads.

This fall, myself and two active friends have been going hiking in different parks, conservation areas and public wild spaces in our area. Whenever we see a new mushroom, we generally stop and take a closer look and we’re often amazed at what we find. In additional to the white, brown and sometimes orange mushrooms, we also find different mosses and lichens. We often taunt each other to try to eat the different mushrooms, but just in jest — recognizing the danger of improper identification.

Mushrooms play an important role in our ecosystem. They are capable of decomposing pretty much any material (plant or animal) in the woods and breaking it down into the primary components of forest soil; providing nutrients that feed the plants growing in it. Many animals rely on mushrooms for food, especially squirrels and other rodents. Slugs also dine on mushrooms, and certain types of flies spend their whole lives on, and in, mushrooms.

Mushrooms develop from a mycelium; a mass of threadlike structures that make up the main part of the fungus. It is usually embedded in soil or wood. These mycelia often form connections, called mycorrhizae, with the roots of coniferous trees and other plants. Unlike plants, mushrooms cannot synthesize their own food from the sun’s energy. They lack chlorophyll – the substance which permits plants to use sunlight to form food. Mycorrhizae assist the plants around mushrooms in absorbing water and nutrients, and in turn, the fungi receives some of the carbohydrates the plant produces through photosynthesis — it’s a symbiotic relationship.

Most interesting to me are the mushrooms that grow in rings. Recently, while hiking the “UpTown” trail in HaroldTown Conservation Area east of Peterborough, we spotted several large rings of mushrooms and wondered how and why they were growing like that. Turns out that when a mushroom spore lands in a suitable location, the underground roots grow out evenly in all directions. As the fungus grows and ages, the oldest parts in the center of the pile die, creating a circle. When the fungus roots produce its mushrooms, they appear above-ground in a ring. The ring continues to grow outwardly, eating up all of the nutrients in its path, and leaving behind nutrient-rich soil.

There are edible mushrooms in our forests like chanterelles, morels, and porcini mushrooms. Also to be found from the fungi family are edible puff balls. Foraging is prohibited in Ontario’s provincial parks without proper authorization and also in conservation reserves, unless the forager is harvesting for personal consumption. In Toronto, foraging for any purpose is illegal in city parks and natural spaces. The Ontario Poison Centre views foraging as an “extremely dangerous” hobby because the difference between safe and toxic mushrooms can be microscopic.

Warning: Never consume a wild mushroom unless you are certain of its identity and edibility. Do not attempt to identify a mushroom from comparing photographs alone. Check out all the characteristics and if in any doubt, do not eat them.

Foraging aside, my suggestion after my experiences this fall is to get out and hike in the forest before the snow falls because there are still thousands of mushroom creatures along the forest floor in different shapes, sizes and colors. It’s a whole new garden in the fall once most of the green has disappeared. Take a camera along with you!

Resources:

https://www.tvo.org/article/where-the-wild-things-are-foraging-in-ontario

https://www.thecanadianencyclopedia.ca/en/article/wild-mushrooms-in-canada

Grow Lights

By Judy Bernard, Master Gardener

It’s getting close to that time of year when our thoughts turn to gardening and starting seeds. The seed catalogues come in the mail in the new year, the Master Gardeners have their Day for Gardeners (pre-covid, this was usually held in late February), and then there’s Seedy Sunday (usually held in mid-March, and still possible for 2022).

Starting seeds in your sunniest south-facing window is your best bet if you don’t have grow lights. When grow lights are used properly, you will have more compact, healthier seedlings to put out in your garden. And grow lights can be used year round to grow veggies indoors. They can be used for houseplants as well.

grow-lights-2683982_960_720

There are lots of different options for choosing grow lights from plant stands with fluorescent or LED lights suspended over your seed flats, to incandescent light bulbs that fit into a standard lamp. There are pros and cons to each type of light. For example, incandescent lights are cheapest, but the most expensive to operate. There is a lot to take into consideration when choosing and selecting the grow lights that will work best for you and the plants you want to grow. I’ve done a little research and found Lamps Plus and Modern Farmer have some good information to help you select and use your lights efficiently.

Resources:

Check out these sites for all you need to know to get started using these amazing lights.

Not Your Everyday Goldenrod

By Cheryl Harrison, Master Gardener

I was recently at a market where a local garden group was selling some plants including many native plants. I noticed a striking goldenrod. I remarked to one of the vendors that it still seems odd to me to see goldenrod for sale when it is so common in rural Ontario. The vendor rightly chastised me because this goldenrod was not your very common goldenrod (Solidago canadensis), it was Gray Goldenrod (S. nemoralis) . The vendor went on to describe some of the positive attributes of this plant. I have to say that the bright yellow, fluffy flowers were beautiful!

This market interaction set me thinking more about the native varieties of goldenrod, or Solidago, species. There are over 100 species of this perennial native with over 25 being found in Ontario. This plant often gets bad press as being a plant whose pollen causes allergies but the likely culprit is ragweed (Ambrosia species). Ragweed and goldenrod bloom at the same time and are often found growing in the same areas. Goldenrod’s lovely yellow flowers (note that there are a couple of Ontario species with white flowers) are attractive to bees and butterflies. They serve as a good source of nectar in the fall and their heavy pollen grains attach easily to the bodies of pollinators. Ragweed flowers are green, do not produce nectar and produce large amounts of light pollen that easily becomes airborne … hence your sneezing and your itchy eyes.

Solidago canadensis, author’s garden

Goldenrod is an easy keeper in the garden. It can grow in a variety of soils, many prefer sun but some grow well in part shade or shade and most prefer average moisture but some can grow well in very moist soil. Goldenrod spreads via seed and through rhizomes (horizontal underground stems). Some species (Tall goldenrod (S. altissima), Canada goldenrod (S. canadensis), and Giant goldenrod (S. gigantea) can quickly take over a small garden. These may be grown in a pot , in a bordered area or in that hot dry area of the garden where not many other plants will grow. This will help to keep them in check.

Goldenrod can be quite a tall plant and is very pretty in drifts in the garden, as a background plant or even as a focal point. I started a woodland garden this year and planted a zigzag goldenrod (S. flexicaulis) which grows in full shade. Goldenrod is great for adding colour to the fall garden and when grown alongside beautiful purple asters (for example, New England Aster (Symphyotrichum novae-angliae), the display is stunning!

Goldenrod has many positive attributes from its beautiful, bright yellow flowers and its tall upright growth habit to the many species that will grow in a variety of conditions including that hot, dry spot in your garden.

Goldenrod may be purchased at most native plant nurseries or grown from seed. For more information on the different species of goldenrod, please check here. For more information on growing golden rod, please check here.

Verbena bonariensis

By Sharleen Pratt, Master Gardener

Verbena bonariensis Courtesy of pixabay.com

I was very intrigued by the plant known as Verbena bonariensis.  This particular Verbena is often shown growing in gardens on the British show Gardener’s World.

I managed to find seeds this spring from William Dam Seeds Ltd.  The package instructed me to start seeds 8 to 10 weeks before the last frost, however, due to a huge demand for seeds the past few years, my package arrived quite late and I was unable to start the seeds until well into April.  At the best of times, Verbena can be an erratic germinator and I was only successful getting one seed to germinate.  However, this one plant was a huge success and I will definitely be trying again next year, although I may be lucky to find some seedlings in my garden.

This plant is one of about 250 species in the genus Verbena. Most are not in cultivation.  It is native to Brazil and Argentina.  Bonariensis means ‘from Buenos Aires, Argentina’.  ‘Buenos’ means ‘good’ and ‘aires’ means ‘air’. It is a perennial in zones 7 to 11, therefore, is grown as an annual in the Peterborough region.  In some milder climates such as California, it can be considered a weed. Verbena bonariensis, also known as Tall Verbena or Brazilian Verbena has stiff upright branching stems.  It reaches a height of 3 to 6 feet and spreads 1 to 3 feet and is unlikely to fall over.  The stiff square and rough stems hold clusters of lilac-purple flowers from early summer right through to late fall.  The deep green, lance-shaped serrated leaves form a mounded rosette at the base of the plant.  The flowers are borne in rounded clusters 2 to 3 inches across.  The cut flowers last a long time in flower arrangements.  England’s Royal Horticultural Society Floral Committee awarded V. bonariensis an Award of Garden Merit (the Society’s symbol of excellence given to plants of outstanding garden value) “because of its attractive flowers and uncluttered habit.” They can make an unforgettable display and although they are tall plants, they have an open and airy appearance which lends them to being tucked in between other plants or even creating a dramatic appearance at the front of a border.  They sway in the breeze and are very attractive to butterflies, bees and other insects.  They prefer full sun to part shade in well-drained soil.

Our very hot summer did not affect its performance and knowing that they are drought tolerant once established is another plus for this plant. There are little known pests or diseases, although powdery mildew can sometimes be a problem.  White spots on the leaves do not seem to have much impact on blooming.

If you leave the flowers to develop seed heads for the birds, the plant may self-seed the following year.  As this was my first season with this plant, I will have to wait until the spring to see if my conditions are good for self-seeding.  I understand that they may not appear until late spring.

It is also possible to cultivate through cuttings and you can find out how to do this in this short video by the very well-known British gardener Monty Don.

Overwintering Dahlias

By Marilyn Homewood, Master Gardener

A riddle, wrapped in a mystery inside an enigma.  Winston Churchill’s famous quotation is the way that I as a novice dahlia grower feel about this subject.  So many variations exist. Can they all be correct??  The answer to this mystery seems to be fine tuning a storage method to suit your own situation, which means some trial and error. So, expect some losses at first.

Pumpkin centrepiece with year end flowers

When to dig? Conventional advice says to wait for the frost but this year’s fine weather made other alternatives a consideration. Dahlias originate from the mountains of Mexico where the fall is semi-arid.  It is the lack of water that causes the plant to go dormant.  Here that happens either with a killing frost or by cutting the plant down. Both cause the onset of dormancy and once begun, the tubers underground start to set “eyes”.  Leave the tubers in ground for 1-2 weeks before digging (this also helps the thin skinned tubers to toughen up, which helps them store better).

Divide now or in the spring?  This is entirely personal preference.  Dahlia are easier to split in the fall as the stalk hardens over winter.  However, the eyes are easier to see in the spring.  If you choose to split in the fall, tubers will need washing and drying before splitting.  For plants being overwintered as a clump, knock off excess soil and let dry before storing.  Some sources conjecture that the fine covering of soil helps to protect the tubers from shriveling over the winter. 

Successful dahlia storage is a balance between the right temperature range and the relative humidity.  Ideally, dahlias should be stored around 45 to 50 F and at a RH of 75-85%.  The method you use should try to ameliorate the conditions you are storing in.  For example, the dryness of the air in winter in Ontario means that shriveling of tubers is more of a problem than rot.  Use of a packing material such as vermiculite or wood shavings can provide a more stable environment, absorbing excess moisture when necessary and giving back when needed. 

Last of dahlias on a sunny October day

Specifics of various techniques are referenced for your information.  I have decided to try 3 methods. I am going to split some this fall and store using the saran wrap method as well as in vermiculite in plastic tubs. I will also leave some in clumps with a slight covering of earth, pack in vermiculite in a large plastic tote.  I lean towards the plastic tubs as my basement in quite dry in the winter so am concerned with moisture retention.  Don’t forget to check your tubers over the winter and remove any ones with rot or spritz with water if they appear to be shriveling. 

Good luck!!

Resources

https://summerdreamsfarm.com/dahlia-care

Peterborough, ON, Canada