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Upcoming Events

05 Oct 2025;
01:00PM - 05:00PM
October Meeting featuring Todd Boland presenting Alpines of the Southern Alberta Rockies
09 Nov 2025;
01:00PM - 05:00PM
November Meeting featuring Paul Zammit presenting Inspirations and lessons I have learned
14 Dec 2025;
01:00PM - 05:00PM
December meeting with Garry Edwards presenting Meadow View Gardens - The Story

What's New!

  • 2025 Meeting Dates
  • Peter Keeping 2025 Clematis List
  • New menu option "ORG&HPS Donations"
  • Alpine Garden Society Zoom Lectures Open to Non-members

Plant of the Month

 

Lunaria annua var albiflora  ‘Alba Variegata’

 

Lunaria annua var albiflora
‘Alba Variegata’

 

Toronto Botanical Garden

Our in-person meetings are held at the TBG.

Plant of the Month for August, 2012

Iris dichotoma heading
Iris dichotoma
 

 (EYE-ris dy-KAW-toh-muh)

General Information:

Known as the vesper iris, the flowers of this plant open at 4:00 pm each day, just in time for evening vespers. This is a collector’s plant; something special for those who like growing plants that none of their gardening buddies have. Although fairly rare in cultavation, the vesper iris is easy to grow and adds a special touch to the garden late in the year when few other plants flower. It flowers for many weeks with each flower remaining open for one day. A well grown plant can have over a hundred flowers.

Iris dichotoma main

Iris dichotoma; photo by Robert Pavlis

The leaves look a bit like a bearded iris, but it has a definite stem and the sword shaped leaves fan out flat on the sides, reminiscent of a Vanda orchid. This is a perennial but some sources claim that it is short lived. Luckily they grow quickly and easily from seed so you can expect some self seedling. Seedlings can flower the first year.

This plant used to be called an Iris and then it was moved to its own genus and called Pardanthopsis dichotoma. As a result of recent DNA studies it has now been renamed, Iris dichotoma. Many references still use the old name.

The Candy Lily, originally called “x Pardancanda norrisii” is a cross between Pardanthopsis dichotoma and Belamcanda chinensis, the Blackberry Lily. The “x’ in front of the name Pardancanda indicates that it is a man-made primary hybrid between two different genera. Both Pardanthopsis and Belamcanda (now called Iris domestica) have now been moved to the genus Iris, so the scientific name of the Candy Lily also had to be renamed. The proposed name is Iris x norrisii, where the “x” now indicates that it is a man-made primary hybrid between two species.

This is all very confusing so let’s get back to the flowers. Plants with all of the above names are similar looking in both plant and flower structure. Iris dichotoma has flowers that are a definite blue-violet colour. The above picture shows the most common coloration, but it can have darker bars on the petals, and have a much darker violet colour. A white version may exist. Belamcanda are shorter plants and have either red or yellow flowers, usually with spots, and open first thing in the morning. The hybrid flowers have a mixture of colours with or without spots. They are shorter than Iris dichotoma and flowers open earlier in the day. The hybrids seem to be long lived.

Iris norrisii 1

Iris norrisii 2

Iris x norrisii; photos by Robert Pavlis

Iris dichotoma has very distinct arms on the flower style. Iris domestica and most hybrids lack this feature, making it a fairly reliable way to confirm the species. Iris dichotoma has brown, elongated seeds whereas Iris domestica and the hybrids have large round black seeds, hence the name Blackberry Lily.

Life Cycle: perennial – short lived

Height: 120 cm (4 ft)

Bloom Time: late summer

Natural Range: Siberia, Mongolia, China

Habitat: moist fertile soil, sandy grasslands, dry sunny areas

Synonyms: Pardanthopsis dichotoma

Cultivation:

Light: full sun 

Soil: normal, well draining soil, tolerates a wide range, pH 6.5 - 7.5

Water: drought tolerant once established, but prefers regular watering

USDA Hardiness Zone:  5 – 10

Propagation: seed

Seedex availability (ORG&HPS annual Seed Exchange): available infrequently (will be there in 2012) 

 
 
 
Requires soaking. Place in warm water until seeds swell, usually 24-48 hours. Discard floaters and the water used for soaking. See https://youtu.be/dhL57pqnHHQ
 
Sow @ 20°C. Seed germinates within 3 months.
Iris dichotoma seed prefers sunshine and variable temperature but rots if too wet. Seeds at milk stage rot without germinating; seeds at dough stage can germinate and have rather high germination rate; fully ripe seeds can germinate without dormancy, and the germination rate is up to 100%. Soak and rinse ripe seed in clean water daily x 4 weeks
Iris dichotoma WRIG 2014
 
 
Robert Pavlis

Plant of the Month for June, 2014

iris cristata alba header
Iris cristata 'Alba'
 

 (EYE-ris kris-TA-da)

General Information:

Iris are popular plants for the sunny garden, but what if you want to grow them in shade? Iris cristata ‘Alba’ fills that role very nicely. It grows best in part shade with a reasonable amount of moisture.

This plant is much smaller than your common garden iris, but it puts on a nice show early in the season, well before the bearded iris. It does not need to be dug up regularly, and so far I have not seen an iris borer on them.

         iris cristata alba main

Iris cristata ‘Alba’ ; photo by Robert Pavlis

The normal colouration for Iris crista, the dwarf crested iris, is dark blue, light lilac, or lavender and the alba form is white with yellow falls. The white one really stands out in a shady area.

The crested iris can be a bit tricky to plant. Out of 4 attempts, 2 have survived. The good news is that once it takes hold, it is quite easy to grow and it spreads fairly quickly—for an iris! The iris likes moisture, but I think it is important that when you plant, you keep the rhizomes uncovered. If they are covered with soil they seem to rot. Once established, new rhizomes grow along the soil surface, fully exposed.

Life Cycle: perennial

Height: 15cm (0.5ft)

Bloom Time: May

Natural Range: Eastern USA

Habitat: calcareous soils, in rich wooded slopes and floodplain forests in dappled shade

Synonyms:  none

Cultivation:

Light: part-shade or sun if given enough moisture

Soil: well drained

Water: even moisture

USDA Hardiness Zone: 3-9

Propagation: seed, division

Seedex availability (ORG&HPS annual Seed Exchange): rarely

 
 
Sow @ 4°C for 3 months, then place @ 20°C for 3 months.
 
Requires soaking. Place in warm water until seeds swell, usually 24-48 hours. Discard floaters and the water used for soaking. See https://youtu.be/dhL57pqnHHQ
sow fresh or soak old seed; prechill 4 weeks or place outdoors over winter and bring indoors once germinated to avoid temperature shock; transplant at 4 leaves
 
 
Robert Pavlis

Plant of the Month for November, 2019

incarvillea mairei header
Incarvillea mairei
 

 (in-kar-VIL-ee-uh  MAIR-ay)

General Information:

Incarvillea mairei, looks very tropical with its large pink flowers. It's hard to believe that such a plant is hardy to zone 3.

Incarvillea mairei: photo by Robert Pavlis

Incarvillea mairei:photo by Robert Pavlis

Known as the dwarf hardy gloxinia, flowering fern or Chinese trumpet flower, it is more compact than other Incarvillea species and seems to be longer lived. I’ve grown several Incarvillea species from seed in zone 5 and most only last a few years. This one has been in the garden for at least 5 years. In colder climates it takes 2 years to flower from seed.

Grows well in full sun, but some reports suggest it might do better in part shade with more moisture. 

As far as I can tell it is not available as an alba form, although alba seeds are sometimes offered for sale. These will be either I. delavayi or a hybrid. 

Incarvillea mairei: photo by Robert Pavlis

Incarvillea mairei:photo by Robert Pavlis

The plant forms a cigar shaped tuber and is occasionally sold as a dry tuber. Plant it with the eye up and the pointy end down, but if you can’t tell which end is up, just plant it horizontally about 3” below soil level.

Life Cycle: perennial

Height: 30cm (12in)

Bloom Time: early summer

Natural Range: SW China to Nepal 2400-4500 m

Habitat: sunny dry slopes

Synonyms:  Incarvillea compacta, Incarvillea grandiflora, Incarvillea racemose, Tecoma mairei

Cultivation:

Light: part shade to full sun

Soil: well drained

Water: average to dry

USDA Hardiness Zone: 3- 9

Propagation: seed, division

Seedex availability (ORG&HPS annual Seed Exchange): common

 
 
Sow @ 20°C. Seed germinates within 3 months.
Incarvillea mairei with Dodecatheon meadia MIDD 2014
 
 
Robert Pavlis

Plant of the Month for September, 2012

hypericum athoum header
Hypericum athoum
 

 (hy-PER-ee-kum ath-oo-um)

General Information:

There are over 400 Hypericum species and all have yellow flowers, usually with 5 petals. They can be annuals, perennials and even shrubs. Hypericum athoum is one of the jewels of the genus making a very nice clump that flowers much of the middle and late summer.

hypericum athoum main

Hypericum athoum; photo by Robert Pavlis

H. athoum makes a nice tight clump. Leaves are 8-15 mm long, ovate to oblong-ovate and softly hirsute (ie hairy). It forms clusters of 2 to 7 yellow flowers, about 15 mm in diameter. The flowers are quite large for the size of the plant.

hypericum athoum closeup

 Hypericum athoum; photo by Robert Pavlis

The common name, St. John’s wort is used to name many of the Hypericum species and is of little use in identifying plants.

A great rock garden plant that deserves to be grown more frequently.

Life Cycle: perennial

Height: 1o cm (4 inch)

Bloom Time: mid to late summer

Natural Range: Greece

Habitat: shady rocks, gravelly soil

Synonyms: none

Cultivation:

Light: full sun to part shade

Soil: humus rich gravelly soil

Water: drought tolerant once established

USDA Hardiness Zone:  range not known – overwinters in zone 5

Propagation: seed and cuttings in late summer

Seedex availability (ORG&HPS annual Seed Exchange): available frequently

 
 
Sow @ 20°C. Seed germinates within 3 months.
 
 
Robert Pavlis

Plant of the Month for June, 2015

Hylomecon japonica header
Hylomecon japonicum
 

 (hy-LOH-mee-kon   juh-PON-ih-kuh)

General Information:

Hylomecon japonica is a special, collectors plant for the shady garden. It is rarely offered for sale, and seed from most seed exchanges will provide the wrong seed. This is a plant that is certainly worth hunting down.

Hylomecon japonica by Robert Pavlis

Hylomecon japonica; photo by Robert Pavlis

The plant forms quite large tubers that start to grow in early spring. In zone 5, the flowers appear early May and continue for about 2 weeks. When flowering is finished the plant has made a nice tight clump of leaves that persist until early summer. At that time the leaves die back, and the plant rests underground until next spring.

Common names for Hylomecon japonica include; forest poppy, Japanese woodland poppy, and Japanese poppy. These common names, and the yellow flowers have led to confusion in the industry. This plant is routinely confused with the other woodland poppies; Stylophorum diphyllum, Stylophorum lasiocarpum and Chelidonium majus.All four plants have similar looking leaves, and similar yellow flowers.

A detailed analysis of each of these species can be found at http://www.gardenmyths.com/hylomecon-japonica-which-is-the-real-plant/

Hylomecon japonica by Robert Pavlis

Hylomecon japonica; photo by Robert Pavlis

S. lasiocarpum has leaves that are distinctly different and can easily be distinguished from the other 3. C. majus is a biennial and the flowers are half the size of the others. Hylomecon japonica and Stylophorum diphyllum can be easily distinguished by their seed pods. H. japonica seed pods are very thin and point straight up in the air. The seed pods of S. diphyllum hang down, and are plump fruits almost as wide as they are long. Once you understand that the 4 plants are similar, they are fairly easy to tell apart.

Hylomecon vernalis may be a different species, but some authorities consider it to be a synonym of H. japonica.

Life Cycle: perennial

Height: 30 cm (1 ft)

Bloom Time: spring

Natural Range: Japan, Korea, China and Russia

Habitat: forest understories, ditch sides, shaded habitats to 2400m

Synonyms:  Chelidonium japonicum, Stylophorum japonicum,

Cultivation:

Light: part shade to shade

Soil: well drained to moist

Water: regular moisture in spring, dry after flowering

USDA Hardiness Zone: 5 – 9

Propagation: seed, division

Seedex availability (ORG&HPS annual Seed Exchange): occasionally

      

 
 

Germination is improved by using GA3. See http://botanicallyinclined.org/fridays-seeds-with-the-ga3-seeds-treatment

 
Sow @ 20°C for 6 weeks, then place @ 4°C for 6 weeks, then slowly raise temperature to 10°C for 6 weeks. If there is no germination, repeat the cycle. This mimics fall sowing outdoors for spring germination.
 
 
Robert Pavlis
  1. Hyacinthoides hispanica
  2. Hornungia alpina ‘Icecube’
  3. Heptacodium miconioides
  4. Helleborus foetidus

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