Thursday, June 3, 2021

Becoming a Plant Sleuth/ How to Grow Bearded Iris

If your new to gardening this spring, welcome. There is so much to learn and discover! 

After you've been gardening for a while, you begin to realize that there are some plants that are difficult to track down. I really want to expand my collection of hellebores this spring, but they are surprisingly hard to find at local garden centers and nurseries.  The reason? I believe that's because hellebores have finished flowering well before the majority of shoppers make their first purchases of the season. 

Hellebores at the Toronto Botanical Gardens

A lily in my garden.

Other plants have the opposite problem. They bloom sometime after June when the majority of consumers have already made their buying decisions. Lilies are a great example. They typically don't flower until July. On top of this disadvantage, their strong central stem looks a bit awkward and unappealing in a plant pot. The sad thing is that lilies are actually a wonderful addition to the garden in mid-summer.

I did find some trilliums at a local garden center this year, but they were teeny-tiny.

Growers naturally prefer plants that provide a quick return that is measured in days or months but not years. A trillium can take seven years to go from seed to a decent-sized, flowering plant. That's a long time to wait for a payday!

Some plants just don't get enough good press. Simply put: not enough people know about them. Native plants are a great example. If asked to name ten native plants, many people would struggle to move beyond Echinacea and Rudbeckia. This lack of demand means fewer companies grow them. Unfortunately, there is nothing more likely to fit easily into your garden than a plant that thrives in your local area.

By now, I think you'll get my point. It can be a challenge to find some of the plants that might be on your wishlist. Don't let that limit you! They are out there just waiting for you to discover them. As your knowledge and experience grow, you'll discover that you need to become a bit of a plant sleuth to track down some of those more intriguing options. 

Searching for interesting and unusual plants might sound a bit like a chore but the hunt can actually be fun and rewarding. The internet makes it easy to seek out specialty nurseries, growers, and mail order companies. 

Lots of these specialty growers offer open houses. As I have written many times in the past, there is nothing like seeing a plant right before you. You don't have to rely on the accuracy of a photograph in a catalog to gauge the flower's true color. When the plant is in front of you, it is also easy to get a clear impression of its mature height and spread. Often I find I have overlooked a plant or combination of plants until I have seen it in someone else's garden.

Bearded Iris 'All the Right Reasons' 

Once the pandemic is behind us, I would encourage you to visit some of these small businesses in person. Last year, I had the pleasure of attending one of the few open houses of the summer. This small business owner had devoted a few acres of his country property to growing irises for sale. Without a doubt, the rows of irises were a labor of love.

Bearded irises are one of those great perennials that don't always make it into garden centers. An iris's bloom stalk is tall and the flowers are easily damaged. It's best to plant irises in late summer/early fall, which is well after the time that nurseries experience the height of retail traffic. If you are lucky enough to find bearded irises, it would likely be a limited selection and nothing like the variety available at this iris farm.

If you are shopping online for bearded iris, it will be easier to read the catalog descriptions if you know these basic parts of the flower.

Tall Bearded Iris 'Queen's Circle' on the left and 'Gypsy Romance' on the right.  

The irises at the far end of the country property.

Tall Bearded Iris 'Falcon Pride'

With satin petals that shimmer in the sunlight, the flower of a tall bearded iris is an exquisite thing to behold. They are perhaps the most iconic iris, but they aren't your only option.

Here's a look at the range of bearded iris available:

MDB: Miniature Dwarf Bearded Irises are the smallest and earliest of the bearded irises to bloom. They grow up to 8 inches tall and have flowers that are three inches or smaller.

SDB: Standard Dwarf Bearded Irises bloom after Miniature Dwarf Iris and usually finish flowering just as the Intermediate Bearded Iris are reaching their peak. SDW reaches a height of 8 to 15 inches tall and has blooms that are 2-4 inches in size.

IB: Intermediate Bearded Irises are 16 to 28 inches in height. The flowers are 3.5-5 inches in size and extend up above the foliage for a nice display.

MTB: Miniature Tall Bearded Irises are 16 to 18 inches tall and have flowers that are approximately 6 inches. The flowers are fragrant and are often used as cut flowers.

BB: Border Bearded Irises are 16-27 inches in height and are more resistant to wind damage than Tall Bearded Iris. At 5 inches the flower size is a little smaller than TB.

TB: Tall Bearded Irises are the last of the bearded iris to bloom. They are 27 inches or more in height.

'Indigo Seas'


Planting a Bearded Iris:

The best time to plant bearded iris is in July, August, or September. To ensure your iris will make it through winter, be sure to plant it at least 4 weeks before the first hard frost. Typically a bearded iris will bloom a year after it is planted.

Iris like full sun (6-8 hours of sunlight). The exception might be a hot climate where bearded irises might benefit from light shade in the afternoon.  The only other requirement is good drainage. If your soil is poorly drained, add organic matter to improve drainage.

Plant your rhizomes at least 12 inches apart. Crowding them can create an impressive display, but you'll have to dig your iris up and divide them after just a couple of years. Spacing irises properly also encourage good air circulation and helps prevent disease.

If your iris is in a nursery container, remove it from the pot without disturbing the soil. Plant it at the same level or even slightly higher in the ground. Be careful not to cover the rhizome with soil. Water well. Continue to water every few days for about a week. Then water weekly until the iris has rooted.

Planting a bare-root bearded iris is a little more tricky. If the roots are looking a little wrinkled you can rejuvenate them by soaking the rhizome in a shallow pan of water (1/4 to1/2 an inch of water) for a couple of hours just before you do your planting. Irises like to have the top of their rhizomes visible to the sun. Dig a planting hole and fashion a hill of soil in the middle. The mound of soil should come up to ground level. Center the rhizome on top of the mound and spread out the roots down the sides of the hill. Bury the roots taking care not to cover the rhizome. Water well. Continue to water every few days for about a week. Then water weekly until the iris has rooted.

Tall Bearded Iris, 'I'm Back' 

Tall Bearded Iris, 'Splashacata' 

Tall Bearded Iris, 'Dancing Star'

Ongoing Care

Established clumps of bearded iris do not need supplemental water. They should be fine with natural rainfall unless there is an extended period of drought.

Generally speaking, bearded iris will do well in average garden soil and do not need regular fertilizer. If your soil is really poor, a light application of fertilizer can be added in early spring and again a month or so after bloom. Superphosphate or a well-balanced fertilizer (with an NKO ratio of 10-10-10 or 5-10-10) are two good options.
There are a couple of fertilizers that should be avoided. A fertilizer that is high in nitrogen can encourage lush growth that is susceptible to bacterial soft rot. A weed and feed fertilizer should also be avoided.

Do not mulch!
Mulch locks in moisture and can cause the soft rot of your rhizomes.

Avoiding Potential Problems
To avoid problems with disease and pests keep your iris clear of garden debris. Remove any dead foliage and after your iris finishes flowering, snap or cut the flower stalk off at the base. In the late summer/fall, prune back the foliage to discourage over-wintering pests.

Tall Bearded Iris 'Ravissant'

Tall Bearded Iris, 'Old Black Magic'

Iris Borers
Adult borers are nocturnal moths that lay their eggs on garden debris in late summer or fall. They hatch into one-inch-sized larvae that chew into the leaves and then eat their way down to the rhizomes. Borer damage is often seen as notched wounds or slimy, wet-looking areas on the leaves. Once they eat their way down to the base of the plant, they begin to hollow their way through the rhizome. In August they pupate in the soil and hatch into more adult moths.

To deal with this pest, I have learned to keep the rhizomes clear of any debris throughout the growing season. I also try to catch the larvae in the spear-shaped foliage by removing any slimy leaves.

Bacterial Soft Rot
It is hard to imagine anything more putrid-smelling than mushy rhizomes infected with this fungal disease. Too much nitrogen in the soil, garden debris around the base of the plants, and too much water are all possible causes of this problem.

Dig up the infected plant/s and cut away the rotten parts of the rhizome (throw the infected sections in the garbage–do not compost them). Allow the cut areas to sit in the open air for a day or two. You can also disinfect the wounds with a solution of 1 part bleach to 9 parts water.

Bacterial Leaf Spot
Small pale spots on the foliage are a sign of a Bacterial Leaf Spot. Sadly there is no cure. Remove any infected plants and wash your tools with a 10% bleach and water solution.

Irises are exquisite flowers, aren't they? 

Sadly, with the ongoing lockdowns, it seems like this will be yet another summer when open houses are impossible (here in Ontario, at any rate). For now, an online search for bearded irises may be your best bet. Typically orders are placed in May and June and are shipped in late summer for fall planting. 

I think you'll find that irises worth doing a little plant sleuthing!

Saturday, May 1, 2021

New Perennials and Shrubs for 2021 from Proven Winners + Some Old Favourites

Sadly, we are in the midst of yet another lockdown here in Ontario. I was surprised and a little relieved to discover that, despite the lockdown measures, nurseries and garden centers are open for a reduced number of shoppers. Plant shopping can finally begin so it's time to start drawing up a wishlist of some new plants along with a few old favourites. 

If you're a fan of Gardener's World, you may remember Carol Klein wandering through a winter garden that showcased red and yellow dogwoods to perfection. I already have red and lime-green varieties, but I have yet to add a Dogwood with yellow stems. Dogwoods are one of the more shade-tolerant shrubs. They also adapt to a wide range of soil conditions. What also interests me about Artic Fire® 'Yellow' is spring flowers and the white berries that follow.

New for 2021 Red-Osier Dogwood, Cornus stolonifera Artic Fire® 'Yellow' is a deciduous shrub that has bright yellow stems that add winter interest to the garden. Arctic Fire® 'Yellow' has tiny, star-like, white flowers followed by white berries. Not available in Florida. Part shade to full sun.  Height: 48-60 inches, Spread: 60-72 inches. USDA zones: 2-7

I saw this next Dogwood when I was scrolling through a wholesale nursery website. I couldn't decide if I liked the shape of the shrub, but I thought the foliage was really interesting. Pucker Up!® might be something I have to see in person before I decide if I like it enough to purchase a plant.

Red Twig Dogwood, Cornus stolonifera Pucker Up!® has heavily textured foliage. Though the stems have a reddish cast this shrub's defining characteristic is its foliage. Adaptable to a wide range of conditions. No flowers. Slow growing so it rarely requires pruning. Not available in Florida. Part sun to full sun. Height: 36-48 inches, Spread: 36-48 inches. USDA zones: 3-8.

To the best of my knowledge, a dastardly vole has destroyed one of my favourite hydrangeas. I am just waiting for some warmer weather to see if any of the rootball of my 'Invincibelle Ruby' survived (I discovered most of the shrub sitting uprooted on the surface of the soil earlier this spring). So heartbreaking! I will probably get another 'Invincibelle Ruby', but if I can't find one, this new introduction might do nicely.

Smooth Hydrangea, Hydrangea arborescens, Invincibelle Garnetta® is a compact, reblooming hydrangea that has big, mophead, pink blooms on strong stems (no flopping like older cultivars such as 'Annabelle'). Full sun is recommended for northern zones. In hot climates some afternoon sun is beneficial. This hydrangea blooms on new wood making it a great choice for northern gardens. Prune in early spring to one-third its size. Fertilize in the spring after pruning. Height: 30 inches, Spread: 30 inches. USDA zones: 3-8.

What can I tell you? I am a sucker for a daylily with a pretty ruffled edge!

New for 2021 Hemerocallis, Rainbow Rhythm® 'Lake of Fire' has a large 7" orange-apricot flower with an orange-red eye. The flower's ruffled edges are orange-red with a razor-thin yellow-gold margin. Average soil and moisture conditions. Part to full sun. Height: 24 inches, Spread: 18-24 inches. USDA zones: 3-9

New for 2021 Ornamental Oregano, 'Drops of Jupiter' has chartreuse foliage and mauve flowers. Though the fragrant leaves are edible, they don't have the flavor of traditional oregano. Average to poor soil with good drainage is ideal.  Heat and drought tolerant. Attracts bees and butterflies. Full sun. Height: 24 inches, Spread: 36 inches. USDA zones: 4-9.

If you've grown traditional varieties of Russian Sage, you'll know they are large perennials that often tend to flop. This new variety is more compact and upright. Russian Sage blooms from summer into the fall, so that's another reason to consider this plant. If you can't find the new 'Sage Advice', 'Denim and Lace' is a second offering from Proven Winners for smaller gardens.

  Russian Sage, Perovskia atriplicifolia 'Sage Advice' has lavender flowers on a strong, upright plant. Grows best in dry to average, well-drained soil. This long-blooming cultivar is drought tolerant. Full sun. Height: 32-36 inches, Spread: 28-32 inches. USDA zones: 4-9.

That I might get excited about something that doesn't flower is a sign that I am evolving as a gardener. I definitely would like to include some new conifers among this year's purchases. I like the texture and the compact size of this native juniper. 

New for 2021 Juniperus communis 'Tortuga' is a low-mounding groundcover with emerald-green foliage. It is a tough evergreen that is perfect for a dry sunny spot. It resists drought, salt, heat, deer, and rabbits. Average to poor soil. No pruning required. Full sun. Height: 24 inches, Spread: 24 inches. USDA zones: 2-7.

I am not convinced this next item is for me, but anyone who grows azaleas might be interested in a repeat bloomer. (Note: This is not a shrub that is ideal for colder zones. If you wish to plant this azalea at its limit of 6b, select a protected location and mulch well)

Reblooming Azalea, Rhododendron, Perfecto Mundo® 'Double Purple' has ruffled flowers. 'Double Purple' first blooms in the spring on old wood, then it experiences a period of growth before it0 puts on new flowers from mid-summer into the fall on new wood. If you need to prune it do so right after the initial flowering in spring (this will also encourage more reblooms). Fertilize in spring. Acidic soil is best. Resistant to lace bug. Sun to part shade. Height: 30-36 inches, Spread: 36 inches. USDA zones: 6b-9.

In my experience, yews are indispensable additions to a shade garden (Note: they can also handle full sun). What interests me about this particular yew is its dwarf rounded habit. You could even use it to replace boxwood as a low hedge.

New for 2021 Yew, Stonehedge Dark Druid® has soft, fern-like evergreen foliage and a compact, rounded habit. Sun to shade. Height: 36-48 inches, Spread: 36 inches. USDA zones: 4-7.

'Paint the Town Fancy' on the left and 'Cherry Vanilla' on the right.

 I have one clump of Dianthus that I've had for years, but generally speaking, I have not been terribly successful with this plant. I put this down to a need for better drainage to see the plants through a Canadian winter. I am not ready to give up just yet. These plants like full sun, and loose, well-drained, slightly alkaline soil. The spicy fragrance of the flowers spurs me into trying again until I am more successful.

New for 2021 Dianthus hybrid, 'Paint the Town Fancy' has fuchsia-pink flowers with a red eye on a low mound of grey foliage.  Continuous bloomer that is heat and drought tolerant. Full sun. Height: 6-8 inches, Spread: 16-18 inches. USDA zones: 4-9.

Old Favourites from Proven Winners

Dianthus hybrid, Fruit Punch®'Cherry Vanilla' has double deep red flowers on a low mound of blue-green foliage.  Continuous bloomer that has a spicy fragrance. Full sun. Height: 8-10 inches, Spread: 8-12 inches. USDA zones: 4-9.

I am redoing a bed at the back of the garden. Weeds moved in when I got wrapped up in other projects and I have decided it is time for a full rethinking of the plantings. Based on increased levels of drought, I want to move away from thirsty plants like phlox. Though the P.W. site suggests that baptisia is "moderately drought-tolerant" in my experience I find they handle drought well, so I am looking back to consider a few older P.W. cultivars. The first is 'Sparkling Sapphires' for the rich color. A white Baptisia might also be nice.

False Indigo, Baptisia Decadence® 'Sparkling Sapphires' has deep violet-colored flowers on a compact plant with deep blue-green foliage. Height: 30-36 inches, Spread: 30-36 inches. USDA zones: 4-9.

False Indigo, Baptisia Decadence® Deluxe 'Vanilla Cream' has pastel yellow buds that open into vanilla flowers. The compact foliage emerges bronze in spring and becomes grey-greenThis cultivar was selected for its petite size and unique flowers. Full sun to light shade. Height: 30-36 inches, Spread: 36 - 42 inches. USDA zones: 4-9.

I ended up buying this next shrub late last summer. The maroon foliage color is what sucked me in– it was wonderfully dark and I thought it might look stunning next to a blue-toned evergreen I also purchased. 

My Monet® 'Sunset' needs winter protection from rabbits.

One issue I have with weigela is rabbits. For instance, I have a 'My Monet Sunset' that gets eaten to the ground every year. This weigela got nibbled a little but not nearly so badly. Was this luck or better rabbit resistance? It's too early to say.

Weigela florida, Spilled Wine® has deep maroon foliage and bright pink flowers. This shrub grows wider than it grows tall. It prefers well-drained soil but is adaptable to a range of soil conditions. Medium moisture conditions. Deer resistant. Height: 76-90 cm (30-36 inches), Spread: 90-106 cm (36 - 42 inches). USDA zones: 4-9.

I fell in love with this shrub when I saw it in Jacquie's garden in Nova Scotia. Pearl Bush is quite an old-fashioned favorite, so I have found it a bit hard to find. Hopefully, I can finally track one down this summer. 'Blizzard' is the tallest of the two options Proven Winners offers. 'Snow Day' is more compact.

Pearl Bush, Exochordax Snow Day® 'Blizzard' has white flowers in the spring. It's an easy-to-grow shrub that flowers on the previous year's growth. This shrub has much larger flowers than the older variety 'The Bride'. Prune to keep it small. Full sun. Height: 60-72 inches, Spread: 60-72 inches. USDA zones: 4-8.

I hope you've enjoyed reading through my list of possibilities. 

By the way, I have gotten a notice from Google saying they are fiddling around again with the workings that send my blog posts to subscribers. I know a number of people have complained already that they no longer receive my posts. Sorry about the confusion! For now, I'd recommend you follow me on Facebook. I don't post on a regular schedule, but I always share a link to each post on my Three Dogs in a Garden Facebook page

I also have an Instagram account if you like to see a selection of my photographs.

Wednesday, April 21, 2021

A Little Cheat with Spring Bulbs

Though warm weather seems to have arrived early here in Southern Ontario, I remind myself that we are only entering the second half of April. Not two years ago we had a snowstorm in the third week of the month. 

This spring we had really pleasant weather up until the end of March when strong gusts and a sudden dip in temperatures made working outside rather unpleasant. At night, the thermometer dipped below zero degrees Celsius. Though it's warmed up once again there is no predicting that the fine spring weather will last.

Over the last couple of years, I've been experimenting with options that can handle the blustery weather we sometimes have in April. I've discovered that there are a few tricks that winter-weary Canadian gardeners can put to good use. 

The daffodils with flower buds in the second week of April.

For guidance as to what to plant, I look to my garden for clues. If the hyacinths and daffodils have flower buds in amongst a good few inches of green growth, it tells me it's safe to think about using pots of forced daffodil and hyacinth bulbs to fill my empty flower pots. 

Tulips in the second week of April.

Generally speaking in the month of April, it's usually a bit early to think about using forced pots of tulips in my container plantings. Again, if I look to my garden, the growth of the tulips is always well behind that of the daffodils. If the vast majority of tulips aren't showing more than a couple of inches of green growth, that tells me it's better to hold off for a week or maybe two before I think about putting pots of blooming tulips outdoors. This year spring is exceptionally mild and I think gardeners in my zone might easily get away with using pots of forced tulips outdoors.

When hyacinths are tightly closed it can sometimes be a challenge to guess their flower color. White flowers have lime green buds. Purple flowers have flower buds that are inky-green.  Green buds that have a dusty rose cast will be pink.

When the month of April proves to be a really cold one, I like to shop for pots of forced bulbs that have tight flower buds that are just beginning to peek up over short green foliage. If the weather remains cold, the bulbs slow down and hold back their flowers. Even though the arrival of fully open blooms may slow, the forced bulbs will still be a little ahead of the regular bulbs planted in the garden.

And as well as being the safest choice, less developed flowers will last a little bit longer than flowers that are already at their peak.

Here's a step by step:

•When I get my pots of forced bulbs home, I check to make sure they are well-watered (so often I find plants at the grocery store are as dry as can be).  Next, I ease my bulbs into the cold by putting the pots outside during the day. 

• For the first few nights, I bring the flowerpots onto our enclosed porch each evening (as an alternative, you could also place them in an unheated garage or even in the trunk of a car. Just be sure to remember they're in the back of your car before you head out!) 

• If it's super cold (below zero Celsius), I might even bring the bulbs inside for the night or cover them (horticultural fleece or even an old sheet will do).

I often plant the bulbs as they are right in their pot. 

• Once my pots of bulbs have acclimatized to outdoor temperatures, I plant them up. This can be done in a couple of ways. You can sink the bulbs, pot and all, right into your container planting. This makes it easier to lift them out once they've finished flowering. 

Alternatively, you can remove the plastic pot and plant the bulbs directly into your container planting Don't worry about teasing out the roots. Leave them as they are unless you want to break up the bulbs and plant them individually.

Companions for Forced Bulbs

Cheerful pansies are one of the first annuals to arrive at garden centres. They're pretty affordable and can handle cold temperatures like troopers. If I can find them, I prefer flats of smaller plants because they are the most economical. 


Pussy Willow branches and pink primula on the right.

Other annual options you might consider could be primula, alyssum and ranunculus. Ranunculus may object if the temperature gets really cold, so you might want to cover them if the weather changes for the worse.

Placing three or five Pussy Willow branches in the centre of my arrangements is my favourite way to add some height to my spring containers. Other options might be Red or Yellow-twig Dogwood or Curly Willow branches.

Other Ways to Use Forced Bulbs

Last fall we were so busy with interior renovations and garden projects, there was little time to plant spring bulbs. If like me, you didn't get around to planting bulbs in the fall, there is still something you can do. 

If, for instance, your garden is looking a little green, you can always inject a little instant color by planting a few pots of forced tulips in amongst your perennials. The tulips will look good for a couple of weeks while the perennials around them continue to develop and move into their bloom phase.

Forced tulips are not reliably perennial, so this is just a quick fix. Once the tulips have finished flowering, add the spent to your compost pile.

As well as filling flowerpots, you can also use forced bulbs in window boxes.

Every spring I tell myself to take pictures and make notes so when fall arrives there is no guesswork as to where to add new bulbs. Despite my best intentions, the spring season is always so busy I never seem to get around to that important note-taking. As a result, I find myself struggling to remember where there were holes in my bulb planting schemes every fall. 

Last spring I tried a new idea that was fairly successful. I filled some of those bare spots that needed bulbs with the spent daffodils and hyacinths from my container plantings. 

A pot of forced daffodils was transplanted into the garden last year and has come 
back again this spring quite nicely.  

Despite the wisdom that says forced bulbs won't return, I have had decent luck getting forced hyacinths and miniature daffodils to return the following spring. Forcing bulbs to bloom indoors is hard on them. Placing them into an outdoor setting where they are allowed to follow a normal cycle improves the odds they will return the following spring.

 Once the flowers have started to fade, I remove the bulbs from my containers, cut off the blooms and plant them in the ground at a depth suitable for the type of bulb. It's very important to allow the foliage to remain exactly as it is. The foliage will feed the bulb that produces next year's flower. 

Not every forced bulb returns, but I count it as a bonus when bulbs that gave life to my containers return for a second show.

P.S. The thermometer dropped last night and we awoke to a blanket of snow. On the plus side, it has already started to melt.

Our white magnolia was gorgeous this year. One woman even stopped to take a picture.

Pink Star Magnolia, Magnolia x loebneri 'Leonard Messel'