Woolly thyme thrives on a sun-warmed rock. (Photo by Brendan Zwelling)

If you’ve had a look at the summer issue of Garden Making, you might notice the editor’s message makes a point about getting the right plant in the right place. A few years ago I planted woolly thyme (Thymus pseudolanuginosus, Zone 5) next to a small granite rock that’s beside the front steps. Sometimes a plant just knows what to do, and this little woolly thyme fell in love with the rock and completely embraced it. Since then, I always plant any form of creeping thyme next to a rock with the hope that they’ll form a happy marriage.

There’s no doubt that thyme likes any kind of smooth stone, probably because the stone has a dry surface and accumulates day heat, providing warmth and perfect drainage. My neighbour learned a similar lesson after years of trying to grow an extensive border of ‘Blue Ice’ bog rosemary (Andromeda polifolia ‘Blue Ice’, Zone 3) along a hot stretch of paved driveway. The bog rosemary suffered a prolonged decline into oblivion, and was eventually replaced with creeping ‘Doone Valley’ thyme (Zone 5). Needless to say, the thyme is spilling out over the stone surface and loving it.

All of which goes to say, I intend to be very thoughtful about where I plant a new, moisture-loving Incrediball hydrangea (Hydrangea arborescens ‘Abetwo’, Zone 4), currently sitting in a pot beside the garage. Incrediball hydrangea is descended from ‘Annabelle’ hydrangea (H. arborescens ‘Annabelle’, Zone 3). ‘Annabelle’ has been perfectly satisfactory for many years, making lots of large white flowerheads from midsummer through frost. But I can be lured by the promise of more and larger flowers (oh, fickle gardener!), and Incrediball promises flowerheads up to 12 inches (30 cm) long, with four times the individual florets in each monstrous head. Yes, I’m overwhelmed, swayed and influenced by flower greed. But consider this: how much more moisture will be required to support the hugely increased flower size? In all the commentary on Incrediball, no consideration is given to its potentially increased need for even more moisture than required by ‘Annabelle’.

I’ll be careful where this new hydrangea goes into the ground and give it the consistently moist soil and frequent irrigation it surely requires. Incrediball might be the right plant to satisfy hydrangea lust, and it’s going to require the right placement.

Other posts by Judith this week:

• ‘Mount Airy’ fothergilla: a new favourite
• Tomatoes love seaweed

Posts by Judith last week:

• The flittering and fluttering of butterflies
• Cherry Bells’ bellflower
• Magnolia ‘Susan’

The bottlebrush flowers on fothergilla. (Photo by Brendan Zwelling)

The large fothergilla (Fothergilla x intermedia ‘Mount Airy’, Zone 5) in the front garden is making a fool of itself with exuberant bursts of fuzzy bottlebrush flowers with chartreuse green centres that fill the air with the scent of honey. This rewarding shrub has quickly endeared itself to me in the two years I’ve had it, and I only wish I’d planted it sooner. The flowers are delightful white puffs that spangle the bare branches, and continue their show as the foliage emerges. The attractive hazel-like leaves are carried on thin, springy branches that bob and weave in summer breezes. The autumn colour is really lovely, too, with yellow-gold leaves intensifying to deep raspberry and burgundy. The leaves keep their colour for three weeks before falling.

This large fothergilla grows five to seven feet (1.5 to 2 m) tall and wide; there is a group of dwarf fothergillas with smaller dimensions. Both large and dwarf specimens like part shade to full sun and moist organic soil. If you have room for the large shrub, it’s worth the space for the display it offers from spring through frost. Plant expert Michael Dirr says, “Fothergillas do not have a bad season.”

Blooming at the same time is little Japanese fan columbine (Aquilegia flabellata, Zone 3) with many milky white flowers and brightly contrasting blue-green foliage. Later this spring I plan to collect its seeds and start them for transplanting near the fothergilla. Their flower colours are identical, and a little skirt of these six- to eight-inch (15- to 20-cm) tall columbines around the fothergilla would be quite charming.

Other posts by Judith this week:

• Thyme: right plant, right place
• Tomatoes love seaweed

Posts by Judith last week:

• The flittering and fluttering of butterflies
• Cherry Bells’ bellflower
• Magnolia ‘Susan’

Fronds of Ascophyllum nodosum. (Photo from Wikipedia.)

Did you see Gayla Trail’s article about cherry tomatoes in the new summer issue of Garden Making? Gayla fertilizes her tomatoes every two weeks with sea kelp diluted in water and gets bumper crops of sweet little tomatoes. The kelp powder I just purchased (Sea Magic, from stokeseeds.com) is the aquatic plant Ascophyllum nodosum, a seaweed wild harvested from the northern Atlantic Ocean (and grows in Canadian waters). The plant looks similar (and perhaps is identical) to seaweed I collected as a child when it washed up on the beach and dried to a crisp in hot sun. It has air bladders on long branches, and it was the greatest fun to pop these bladders and get a loud noise. Little did I know there would be other, more important, uses for this ocean weed later in my gardening life.

Ascophyllum seaweeds are used as fertilizers for all kinds of food and ornamental crops, and deliver low amounts of the main plant nutrients, as well as a broad selection of micronutrients. Most important, seaweed contains plant hormones (called auxins) that promote plant growth and disease resistance, increase bud and fruit production, and build winter hardiness. (Colour depth and fragrance are increased in roses.)

The magic ingredients are cytokinins and gibberillins, amino acids and proteins, all essential elements gardeners have been supplying to plants since ancient Egyptian times. Providing plants with a foliar drench every two weeks results in quickly appreciable results. Do we need to say anything more? Let’s get some!

Other posts by Judith this week:

• Thyme: right plant, right place
• ‘Mount Airy’ fothergilla: a new favourite

Posts by Judith last week:

• The flittering and fluttering of butterflies
• Cherry Bells’ bellflower
• Magnolia ‘Susan’

Nincompoop is based in Kitchener, Ont., and as advertised in Garden Making, sells an “eco-friendly, weed-free, wood-free and odourless line of organic ‘Earth Products’ and ‘Weed Resistant Mulch’.”

You can find out more at Nincompoop.ca or from the ads in our magazine.

Peterborough Show winners

• Vivienne B. of Bobcaygeon
• Cauleen V. of Peterborough
• Melissa L. of Peterborough

Stratford Show winners

• Elizabeth C. of Aylmer, Ont.
• Sue M. of Cambridge, Ont.
• Julie C. of London, Ont.
• Rick N. of Chatham, Ont.

The red admirals arrived early this spring. (Photo by Brendan Zwelling)

After yesterday’s sunny warmth, flower buds are opening with the speed of time-lapse photography. I could actually watch the blossoms spring open on my weeping ‘Red Jade’ crabapple. The tree is now covered by dozens of red admiral butterflies (Vanessa atalanta), competing with bumblebees for nectar and doing a terrific job of pollinating the flowers. The tree is quivering with activity and I can look forward to a bumper crop of ornamental crabapples this autumn.

The butterfly migration began early this spring with the arrival of an unusual number of red admirals. Clouds of them have been swept in by high winds from the south, and they descended on gardens in hordes, covering flowering trees and working their way through spring bulbs and early flowering weeds. They’re easily recognizable by their velvety brown wings banded in bright orange and tipped with white blotches on the dorsal forewings. There’s sometimes confusion between the red admirals and American lady or painted lady (Vanessa cardui) butterflies, which have identical colours, with the orange pigment in the central part of their wings. But if you see a cloud of orange and brown butterflies in your garden this week, they are surely red admirals.

It goes without saying that this is a very good sign of a bountiful summer to come. Red admirals are wonderful pollinators, and will sip nectar from flowers of ornamental and food plants, as well as dandelions and thistles. The first wave this year is larger than ever seen before, according to scientists at the Royal Ontario Museum and the Toronto Entomologists’ Association.

These initial butterflies will lay eggs and start a potential two to three generations hatching this season. The caterpillars are fussy about food and will eat only stinging nettles (Urtica dioica), and how good is that? If you’ve ever had a painful encounter while weeding stinging nettles, you’ll know how fortunate it is that red admiral caterpillars want to eat them. When the eggs hatch, emerging brown caterpillars eat nettles for a while, then roll themselves up in a leaf to pupate, later emerging as a red admiral butterfly. Take care not to damage them in their leaf cocoons, and they’ll soon reward you by pollinating your tomatoes and peppers.

Further good news is that my little hummingbird has returned. It was seen yesterday feeding in the ‘Olga Mezitt’ rhododendrons that are in full, lipstick-pink bloom. I began a flurry of activity, changing the syrup in two hanging feeders and setting out “lures” of red salvias and geraniums acquired this week.

This hummer has been coming to the garden for several years, stopping briefly in May, and then again in August, on its annual migration. It’s probably headed to Algonquin Park in northern Ontario, where I see dozens around the feeders there in late summer. Last year, my hummer discovered the feeder hung in a front garden tree, and I hope that will encourage a longer visit this spring. I certainly have lots of good nesting sites to offer, and a steady diet of nectar from thistles and dandelions, as well as a la carte sugar water service from the kitchen. Yes, the garden is full of life, and it’s good.

Other posts by Judith this week:

• ‘Cherry Bells’ bellflower
• Magnolia ‘Susan’

Posts by Judith last week:

• Community birdbaths
• Pumpkins as groundcover
• Early viburnums

‘Kent Bells’ campanula (Photo courtesy of Balamore Farms Ltd., Nova Scotia)

Oh, I’ve been plant shopping. This wasn’t a major planned expedition; that happens later this month in the Niagara region. But I’ve been making some quick visits to garden centres along the way to other events, and I’ve found more of some favourites to add to those I already have. One is spotted bellflower (Campanula punctata ‘Kent Bells’, 18 x 24 in / 45 x 60 cm, Zone 4), which has been in the front garden for several years. It also makes a beautiful cut flower.

The bellflowers are a prolific and varied group, usually characterized by dangling, bell-shaped flowers. The descriptive term punctata (meaning pricked or dotted) refers to spots inside the flower’s bell tube that can only be seen by turning one up and peering inside. (Sometimes, on cool summer mornings, I find a sleeping bee in there.)

‘Kent Bells’ has hanging clusters of large, deep violet-blue bells above clumps of fresh green foliage, and grows in part shade to full sun. The plant spreads by underground rhizomes and is known to become invasive, but so far that hasn’t happened in my garden. I have it in too much shade, and that’s possibly the reason it remains politely in place.

I was pleased to find a pot of ‘Cherry Bells’ with deep rose-pink bells, reputedly larger than the blue flowers on ‘Kent Bells’. Now I’m looking for ‘Wedding Bells’, with intriguing hose-in-hose flowers, assembled with one flower inside another, as seen in some primula species. The flowers are white, with deep raspberry spots inside the bells. I don’t know what a bee would make of this double tube arrangement. Although there is the possibility of spreading rhizomes, I can’t feel worried about that. After all, this is a beautiful plant! If there’s too much of it, I’ll just pot up some divisions and share them around.

I also came upon some lovely ‘Obsidian’ coral bells (Heuchera ‘Obsidian’, Zone 5), with shiny purple-black foliage that will make an exciting contrast with early gold daylilies (already in bud) and variegated green and white ‘Patriot’ hostas. More excitement is always welcome, and I bought two of the dark coral bells.

There are several dark-leaved coral bells around, but often their foliage seems drab and fails to complement companion plants. ‘Obsidian’ leaves have a definite shine, like sequins in the flowerbed. And sequins are some of my favourite things!

Other posts by Judith this week:

• The flittering and fluttering of butterflies
• Magnolia ‘Susan’

Posts by Judith last week:

• Community birdbaths
• Pumpkins as groundcover
• Early viburnums

Long-blooming 'Susan' magnolia. (Photo by Brendan Zwelling)

Many of the early-blooming magnolias (such as cultivars of M. stellata and M. x soulangeana) were tricked into opening early, only to be burned by sharply falling temperatures a few days later. Magnolias are fools when it comes to sudden warmth and throw caution to the wind, rapidly popping buds and splaying open their flowers. I was fortunate to avoid this fate with my ‘Susan’ magnolia (a cross between M. liliiflora ‘Nigra and M. stellata ‘Rosea’), which opened its flowers last week and continues to bloom.

An infection of bark scales devastated my first collection of seven magnolias several years ago. Some years passed without magnolias in my garden, which is as painful a deprivation as the absence of roses. Cautiously, I began bringing magnolias back, watching carefully for the scale insects. The first re-introduction was ‘Susan’, a compact shrubby plant (8 x 8 ft / 2.5 x 2.5 m, Zone 5) with rounded form good for specimen planting or for informal hedging in a large open space. The mildly scented flowers have strappy purple-pink petals, opening from dark purple buds. The colourful display lasts about three weeks in cool weather.

Last year I planted a young ‘Butterflies’ magnolia (16 x 8 ft / 5 m x 2.5 m, Zone 6) with non-fading bright yellow flowers, broad leaves and a pyramidal shape. My specimen is a multi-stem shrub, and can be pruned to keep an airy, open form. So far it has clean bark with no sign of scales, and I hope the cycle was broken by starving the scales out. Bringing magnolias back into the garden is a risk I’m willing to take in order to enjoy these gorgeous plants.

Other posts by Judith this week:

• The flittering and fluttering of butterflies
• ‘Cherry Bells’ bellflower

Posts by Judith last week:

• Community birdbaths
• Pumpkins as groundcover
• Early viburnums

Fisher Library exhibition

A wonderful exhibition of gardening literature is now open at the Thomas Fisher Rare Book Library at the University of Toronto.

The exhibition of British and Canadian works on horticulture from the library’s collections (augmented with some private loans) is a fascinating review of how books, catalogues, periodicals and other media have helped to spread knowledge about gardening over the centuries. The title of the exhibition, “How Does MY Garden Grow: The Education of a Gardener,” is inspired by Russell Page’s The Education of a Gardener, a work which perfectly combines mastery of the history and craft of gardening with a deep and personal love of plants, says Anne Dondertman, Acting Director of the Fisher Library and a gardener, who devoted several years to assembling the exhibition.

The exhibition is open to the public, and will run until Sept. 14, 2012.

Drawing on the rich printed and manuscript resources of the Fisher Library, the exhibition approaches horticultural history from the particular viewpoint of how people learn to cultivate plants—both historically and as individual gardeners today. As outlined by Dondertman, there are three main sections:

• Learning from the written word, beginning with the teachings of antiquity and moving on through five centuries of printed knowledge as recorded in books, periodicals and now online sources.
• Learning from observing plants in the wild, in public and private gardens, and in botanical gardens and commercial nurseries.
• Learning from our own experiences as gardeners, as documented in the personal records of individual gardeners in their own plant lists, diaries and garden journals, and blogs.

The accompanying catalogue prepared by Dondertman is generously illustrated.

Garden Making is honoured to have been included as a more recent example of the continuum of resources for gardeners.

The Thomas Fisher Rare Book Library is located at 120 St. George St. in Toronto.

Judd viburnum blossoms are highly fragrant. (Photo by Brendan Zwelling)

The past two weeks of near-freezing night temperatures have made frost damage to emerging perennials a threat. However, there’s always a silver lining, and the viburnums love this extended cool period. I have four viburnums with perfumed flowers that bloom sequentially (one beginning as another is finishing), and their season started when ‘Dawn’ arrowwood viburnum (Viburnum x bodnantense ‘Dawn’, Zone 6) burst into bloom in early March, and lasted for a full month. I have two of these, because I’m greedy about anything blooming so early; one is by my office window.

Next to bloom is Burkwood viburnum (V. x burkwoodii, Zone 6, possibly Zone 5 if not in a windy location) that fills a back corner. Its dark green foliage has an attractive lustre that shines in sunlight all summer, and the many white flowers have a spicy scent that moves across the garden in waves. (Woody plant expert Michael Dirr says this is a favourite in his garden, where it asks little and gives much.)

My favourite, Judd viburnum (V. x juddii, Zone 5), blooms next, and is planted under the living room window where I can keep an eye on it. It produces beautiful creamy flowers from bright pink buds, and is highly fragrant. The perfume is impressive, and some think this might be the best of all the scented viburnums (and I agree). The Judd viburnum is now in full bloom, and will be followed by its fragrance rival, Koreanspice viburnum (V. carlesii, Zone 5), which has this morning opened its first flower. The buds and eventual blooms on Koreanspice viburnum are the most substantial of all these shrubs, with semi- hemispherical cymes of white flowers with thick waxy petals.

These viburnums fill the early spring air with delicious scent for at least six weeks, and make the most of cool temperatures. All this, even before we get to the first lilacs!

Other posts by Judith this week:

• Community birdbaths
• Pumpkins as groundcover

Posts by Judith last week:

• Making sense of fertilizers  
• ‘Pink Charm’ narcissus
• PJM rhododendrons

'Gladiator' pumpkins. (Photo courtesy of stokeseeds.com)

Last week a young hemlock had to be taken down at the back of my garden, a victim of high summer temperatures with insufficient moisture. Yes, I’m the guilty party, and very sorry for my neglect of this tree’s simple need for regular irrigation. I’ll be over-compensating all season, delivering fertilizer, water, staking and providing every form of assistance required in this garden!

With the tree gone, there’s a wide space of rough ground with many substantial weed colonies. I see weeks of digging ahead, trying to get this under control. What to do? I could attempt to smother the weeds with dark plastic, but that would be quite unsightly in such a large area. I could douse the plants with a vinegar-based herbicide, but it would take multiple applications over the summer, and the garden would smell like salad dressing.

I decided to postpone the substantial weed removal work until autumn, and look for a temporary “green” solution for the summer. That’s when I thought of pumpkins. Nothing grows faster than pumpkins, which send their vines out along the ground and produce lots of wide green leaves. I can dig two or three holes, dump a bag of composted manure in each, and set out pumpkin plants. When the taller weeds poke their heads up, I’ll just remove the tops (to prevent seeding) and worry about their roots in autumn. I hope I get some pumpkins, too!

I was startled to discover the size of fruits and cost of some hybrid pumpkin seeds. Looking at a catalogue (stokeseeds.com), I was interested in ‘Full Moon’, an open-pollinated pumpkin, producing startling white fruits, each weighing 60 to 88 pounds (27 to 40 kg). A packet contains five seeds, costing $10! (Because ‘Full Moon’ is open pollinated, saved seeds will come true and be identical to the parent.) Well, it’s too big, anyway. I’ve settled on ‘Gladiator’, a classic dark orange pumpkin with sturdy stems, weighing 20 to 30 pounds (9 to 14 kg). I’m betting that if I get any fruits, they won’t reach full size in only a half day of sun. But then, you never can tell when a pumpkin planted in a hill of manure might get just enough of a power boost and conquer the earth.

Other posts by Judith this week:

• Community birdbaths
• Early viburnums

Posts by Judith last week:

• Making sense of fertilizers  
• ‘Pink Charm’ narcissus
• PJM rhododendrons