(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; 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; 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

 (hy-uh-sin-THOY-deez his-PAN-ih-kuh)

General Information:

Hyacinthoides hispanica, or Spanish bluebells are one of the best spring bulbs. Any type of bluebell is a great addition to the garden, but Spanish bluebells put on a better show than most of the others. They flower later than other bluebells and are much taller, allowing them to make a big splash in the garden.

Hyacinthoides hispanica; photo by Robert Pavlis

Hyacinthoides hispanica are also called wood hyacinth, and scilla. They are native to Spain and Portugal but have become a relatively common plant in many countries. They like part shade, but I grow them in full sun which they seem to like in zone 5. They are deer and rodent resistant and will grow in just about any soil. Plant them and forget them.

Hyacinthoides hispanica; photo by Robert Pavlis

The other common blue bell is the English bluebell, Hyacinthoides non-scripta. The Spanish bluebell is much taller, has flower bells on all sides of the stem and the flower stem is more upright. The Spanish bluebell has blue anthers while the English or common bluebell has creamy-white ones. The two species cross breed easily and garden plants may be hybrids.

Available in white, pink and various shades of blue.

Life Cycle: perennial bulb

Height: 40 cm (1.5 ft)

Bloom Time: late spring

Natural Range: Spain and Portugal

Habitat: woodland edges

Synonyms:  Endymion campanulatus, Endymion hispanicus, Scilla campanulata, Scilla hispanica

Cultivation:

Light: full sun to shade

Soil: not fussy

Water: regular moisture in spring, drought tolerant in summer

USDA Hardiness Zone: 3 - 8

Propagation: seed, offsets

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

 (hor-HUNG-ee-a AL-pin-ah)

General Information:

A darling plant for the rock garden that is not very well known, especially in North America.

Hornungia alpina forms a nice solid tufted clump with small pinnate fresh green leaves that look good all year round, even in winter. The plant is reported to bloom in early spring (March to April), but mine blooms almost continuously from mid summer into late fall. In my zone 5 garden this is the last plant to have open flowers – still going strong in late November.

Comment added June 9, 2013: This year the plant started to flower in late April and it has been covered with flowers ever since.

Hornungia alpina ‘Icecube’; photo by Robert Pavlis

The flowers are slightly fragrant, white and typical of the mustard family. As flowers fade, the flowering stem elongates and new flowers are formed on the same stem. No wonder the variety ‘Icecube’ is a Quality Award winner.

I originally had the plant growing at ground level beside larger neighbours where it grew well but did not shine. This year I moved it to a trough and it is the star of the show. Over a few years it might get too big for a trough without some pruning.

Hornungia alpina ‘Icecube’; photo by Robert Pavlis

The plant has had several names. It’s common name is chamois cress. In Europe it is better known as Pritzelago alpina and in North America it is known as Hutchinsia alpina.

Life Cycle: perennial

Height: 10 cm (4 inches)

Bloom Time: early spring to late fall

Natural Range: Southern and central Europe

Habitat: Mountains

Synonyms: Noccaea alpina, Lepidium alpinum, Pritzelago alpina, Hutchinsia alpina.  

Cultivation:

Light: full sun 

Soil: loam or sandy soil

Water: average moisture

USDA Hardiness Zone: 4 - 9

Propagation: seed

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

 (hep-tuh-KOH-dee-um  mik-on-ee-OY-deez)

General Information:

Heptacodium miconioidesis a small tree or large shrub that provides year long interest, especially in late summer and fall when it appears to flower twice; once in white and then again in red. The white flowers form in bunches of 7 which gives the plant its common name of seven sons plant. After flowering, it forms small fruits and red calyx that are as large as and showier than the flowers.  

Heptacodium miconioides mature tree:photo by Robert Pavlis

In addition to the floral display, it has a great open structure and exfoliating bark. The flowers are smaller and reserved, but covered with bees and other insects. Other common names include Seven son flower, crape myrtle of the North and autumn lilac. It has few insect and disease problems and is easy to grow.

Heptacodium miconioides flowers:photo by Robert Pavlis

Heptacodium miconioides calyx:photo by Robert Pavlis

H. miconioides can be pruned into various forms. It can be kept short and bushy to make it look like a tall shrub or it can be pruned into a single-stemed tree. I prefer a form in between these two extremes; a shorter multi-stem,  fountain-shaped structure with the lower sections kept open and free of branches. In this way you can enjoy the great bark and see the flower display at or just above eye level.

This tree was discovered in 1907 by E. H. Wilson on an expedition to China. It remained a great secret until 1980 when new seeds and cuttings were brought back to the US for propagation. Since then it has become more popular.

Heptacodium miconioides exfoliating bark:photo by Robert Pavlis

Life Cycle: tree

Height: 450cm (15 ft)

Bloom Time: fall

Natural Range: China

Habitat: Part shade, mountainous regions

Synonyms:  Heptacodium jasminoides

Cultivation:

Light: full sun

Soil: wide range of soil

Water: medium moisture

USDA Hardiness Zone: 5 – 9

Propagation: seed, soft-wood cuttings

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