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Gentiana septemfida

Skill Level: Intermediate (germination)

Gentiana septemfida—the Crested Gentian from the cool, open slopes of the Caucasus Mountains—is one of those alpine perennials that stops gardeners in their tracks. Low, mounded, and quietly handsome for most of the season, it suddenly erupts in mid to late summer with oversized, intensely blue trumpets that look almost tropical against its tidy green foliage.  Added bonus: it is by far one of the easiest Gentiana to propagate and grow.

In the wild, it grows in subalpine meadows and grassy, moisture‑retentive slopes, often fed by long‑lasting snowmelt. In gardens, mature plants reach 8–12 in., forming a loose, spreading clump that fits beautifully at the front of a border or in a rock garden. It prefers full sun in cool climates or part sun where summers run hot, with moist, humus‑rich, well‑drained soils.

Our Seed Germination Experience

The seeds are fine and fall into the “intermediate” category mainly because they require the same careful handling as other very small seeds. They are orthodox, but viability declines quickly.  In our experience, it is best to work with seed less than 6 months old. Older seed can still germinate, but rates drop sharply.

A complicating factor is the high proportion of chaff typically mixed with the seed. It is very difficult to separate, and germination percentages may reflect this more than any inherent reluctance of the species.

We’ve had the best results with a surface sow technique: sow on the surface of a firmed, moist medium, avoid covering, and maintain steady humidity. Our fresh seed germinated in 3 weeks at a cooler room temperature (65°F).

Seedlings are small at first and require careful watering and bright, indirect light. Once established, they grow steadily and appreciate cool roots, and consistent. With good care, seedlings should reach flowering size within 2–3 years.

Photo: friedrichstrauss.de

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Primula kewensis

Skill Level: Beginner/Intermediate

Primula kewensis, often called Kew Primrose, is one of those horticultural curiosities that reminds us how generous the Primula genus can be. A naturally occurring hybrid between Primula verticillata and Primula floribunda, it first appeared at the Royal Botanic Gardens, Kew—an unexpected seedling that went on to charm gardeners with its bright yellow blooms and spectacular leaves. A signature feature of Kew Primrose is the soft grey farina—a natural powdery coating on the leaves and stems that gives the plant its silvery, ethereal appearance. Though technically a hybrid, it behaves with the reliability of a species and has been cultivated for more than a century.

In cultivation, P. kewensis forms neat rosettes and typically grows 10–14 inches tall and 8–12 inches wide. It thrives in partial shade and humus rich, evenly moist soil with good drainage—classic primrose preferences. Hardy in Zones 6–8, it performs beautifully in woodland borders, along paths, or in lightly shaded beds where the soil never fully dries.

Blooming begins in mid to late spring, followed by sporadic flowering through summer whenever conditions remain cool and moist. This extended, stop and start bloom pattern is one of its charms, offering small surprises long after the main spring show has passed.

Our Seed Germination Experience

We classify Primula kewensis as beginner/intermediate level. It benefits from cold stratification, but it is not absolutely required. Germination is triggered by cool temperatures (10°C to 15°C), not deep dormancy. Like all primulas, the seed is short lived—viability drops sharply after 12 months—so sow as soon as possible after harvest for the strongest germination.

Light aids germination, so we recommend barely covering seed so that around 50% are still visible. Although not required, seeds benefit from cold stratification, either naturally outdoors or via refrigeration.

At Spirithouse Gardens, we sow our seed outdoors in December in an unheated Zone 8 greenhouse, allowing winter to provide the chill. Germination typically occurs about 90 days later, in March, as temperatures begin to rise. This method has been reliably successful for us, though the refrigerator method works well for those in warmer climates.

Seedlings grow steadily once established, and plants usually flower in their second year, though vigorous autumn sown seedlings may bloom earlier if they receive their cold period promptly.

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Erythronium tuolumnense

Skill Level: Advanced

Erythronium tuolumnense, known as the Tuolumne Fawn Lily, is one of the “easiest” erythronium to start from seed with erythronium being notably difficult. Its clear, glossy green leaves emerge in early spring, smooth and luminous, forming a low rosette that seems to glow in cool light. Soon after, slender stems rise to carry elegant, reflexed yellow flowers — each one poised like a tiny lantern above the foliage. Mature clumps reach 10–14 inches tall, spreading slowly into tight, graceful colonies.

This species is native to the Sierra Nevada foothills of Tuolumne County, California, where it grows in cool, humus‑rich woodland soils. It thrives in dappled shade, consistent spring moisture, and well‑drained, leafy loam that dries slightly as the plant enters summer dormancy. Hardiness is generally Zone 5, with some growers reporting success in sheltered Zone 4 sites. Bloom time is mid to late spring, depending on snowmelt and local temperatures.


Our Seed Germination Experience

Erythronium seeds are orthodox, meaning they tolerate normal drying, but they are also very short‑lived. Fresh seed is strongly preferred. Although no published studies quantify longevity under dry storage, we’ve consistently seen germination drop after even a single year. For best results, sow in the same season the seed is harvested. It has been reported that seeds collected green should rest a few days before sowing, as they are prone to rot.

Erythronium have a shallow physiological double dormancy, meaning the dormancy is easy to break, but the process still requires two full seasons—one warm/cold cycle to produce the root, and a second warm/cold cycle to produce the shoot.

Because of this, they are excellent candidates for both the “Baggie Method” and the “Move‑along Method” described by Carol and Jerry Baskin. Sow seed in an inert, moistened medium in a clear plastic bag so the stages can be observed. A brief warm stratification is required; we found 14 days at room temperature sufficient. Move the seedlings into the fridge for about 2 months. Once a root appears in the fridge, move the seeds back to a cool room temperature for a second warm period. The cotyledon will emerge and then pause. Because the ideal temperature for this phase is likely slightly cooler than typical room temperature, and no research‑based recommendation exists, we used 2 months. During this time, seedlings appear stalled, producing no true leaves. Only after a second cold period—again, we used 2 months—do true leaves begin to develop.

Alternatively with less control, seed can be sown outdoors in zones 7 or 8 in early fall for natural warm stratification. If moved to an unheated greenhouse that does not freeze for long stretches, the seed will experience alternating cold and warm periods through winter. Depending on the degree and duration of these fluctuations, either cotyledons or true leaves may appear in spring as temperatures rise.

This is a seed for a patient grower, typically requiring 4–6 years to reach blooming size. Since Erythronium are ephemeral, the entire growth cycle to develop the bulb is done within a 12 week period. In cooler climates or deeper shade, 7 years is not unusual.

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Syneilesis aconitifolia

Skill Level: Beginner (germination)

Syneilesis aconitifolia—the Shredded Umbrella Plant from the cool, wooded slopes of Korea, Japan, and northeastern China—is one of those woodland perennials that catches attention. In early spring, its silky, ghostlike shoots push through the soil like miniature parasols, slowly unfurling into finely cut, almost paper‑delicate umbrellas that look more sculpted than grown. Mature plants reach 18–24 in., forming tidy, slowly expanding clumps that lend a quiet architectural sophistication to part‑shade gardens. It prefers humus‑rich, moist but well‑drained soils and is hardy to roughly USDA Zone 4. In mid to late summer, slender stems rise above the foliage carrying clusters of pale, curiously configured flowers that hover like fairies with parasols.  But as the name suggests, you grow a shredded umbrella for the leaves.

Syneilesis aconitifolia Emerging

Our Seed Germination Experience


Although Syneilesis aconitifolia is rarely offered, the seeds themselves are surprisingly cooperative. They are orthodox but short‑lived, so fresh seed performs best. Sow at room temperature, cover lightly or not at all, and maintain even moisture. Our seed is usually less than six-months old, and consistently germinates within two weeks. Plants are slow to reach full size, but with good care, young seedlings should produce their characteristic shredded leaves by their second year.

The reason this plant is not more widely available has nothing to do with germination difficulty and everything to do with seed production. Syneilesis aconitifolia sets very few seed because it is strongly self‑incompatible: a single plant, or even multiple divisions of the same clone, cannot pollinate itself. Two genetically distinct individuals must flower at the same time for viable seed to form. Even then, the flowers attract few pollinators, and their intricate structure makes pollen transfer inefficient. Combined with the short viability of the seed, this explains why fresh seed is so rarely encountered and why growers treasure every viable achene they can collect.

Photo: Spirithouse Gardens and rtbf.be


#SyneilesisAconitifolia #ShreddedUmbrellaPlant #WoodlandPerennials #ShadeGarden #RarePlantsFromSeed #UmbrellaPlant #BotanicalCuriosities

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Lilium pumilum

Skill Level: Beginner

Lilium pumilum, often called the Coral Lily or Siberian Coral Lily, is a graceful, small‑statured species native to Siberia, Mongolia, northern China, and Korea. Unlike more demanding lilies, it forms tidy clumps of narrow foliage topped with delicate, nodding, coral‑red Turk’s‑cap flowers. Mature plants reach 18–30 inches tall, making them ideal for the front of the border, rock gardens, and meadow‑style plantings where their vivid colour and airy structure shine.

It thrives in full sun to light shade, in well‑drained, humus‑rich soil that stays evenly moist but never waterlogged. Its origins in open, grassy slopes and forest margins give it a surprising tolerance for a range of soils, provided drainage is good. Hardy to Zone 3, it emerges in mid‑spring and begins blooming in early to midsummer, often producing a generous flush of flowers even at a young age.

Our Seed Germinating Experience

This is a beginner‑friendly seed—one of the easiest lilies to start. Lilium pumilum produces orthodox seed, meaning it tolerates drying and stores well. When kept cool and dry, seed remains viable for 3–5 years, with only a gradual decline in germination over time.

We sowed our batch at room temperature (around 70°F), with nearly all seedlings emerging within a week.

Seedlings grow quickly but are highly attractive to slugs, which can devastate a tray overnight or prevent young bulbs from emerging.

Seed‑grown bulbs size up steadily, and most plants will bloom in their second or third year, with exceptionally vigorous seedlings flowering even earlier if sown very early in the season.

Photo: Alberta Regional Lily Society

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Pelargonium endlicherianum

Skill Level: Beginner

Pelargonium endlicherianum, often called the Armenian Pelargonium, is a compact, jewel‑toned perennial species native to the rocky uplands of Turkey and the Caucasus. Unlike the tender bedding pelargoniums most gardeners know, this one is a true hardy species—forming neat mounds of divided, slightly aromatic foliage topped with vivid magenta‑pink flowers. Mature plants reach 12–18 inches tall and wide, making them ideal for rock gardens, gravel beds, and sunny borders where their saturated colour reads beautifully against stone and silver foliage.

It thrives in full sun and well‑drained, gritty soil, reflecting its origins in dry, mountainous terrain. Ordinary garden soil works well as long as drainage is sharp; this is not a plant for heavy, winter‑wet conditions. Hardy to Zone 5, it emerges in mid‑spring and begins blooming in late spring to early summer, often continuing in flushes through the warm months if spent flowers are removed.

Our Seed Germinating Experience

This is a beginner‑friendly seed that germinates reliably at room temperature. After sowing, our batch began sprouting in just over two weeks, with additional seedlings appearing steadily over the following several weeks. Germination is not instantaneous, but it is consistent—an easy, low‑stress process ideal for new seed starters.

Because this species comes from a climate with warm summers and cool nights, gentle bottom heat can speed germination slightly, but it is not required. Room‑temperature conditions (around 65–70°F) are perfectly adequate, and seedlings grow quickly once they develop their first true leaves. The young plants are sturdy, compact, and eager to establish.  Seeds sown early may produce exploratory blooms in the first year.  Expect seed grown plants to flower in their second year.

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Arisaema tortuosum

Skill Level: Intermediate

Arisaema tortuosum, the Whipcord Cobra Lily, is one of the most striking members of the genus. Growing 3–6 feet tall, it forms a single pseudostem topped with an umbrella‑like leaf, while the long, threadlike spadix rising above the hood gives the plant a distinctly sculptural presence in the woodland garden. In its native Himalayan range, it emerges in late spring and blooms in early to mid‑summer.

Hardy to zone 6, where corns do not freeze solid, this species thrives in bright shade to dappled light and tolerates more sun than many of its relatives provided the soil remains evenly moist. It prefers humus‑rich, well‑drained woodland soil, but it is notably more forgiving than the fussier Himalayan species such as A. griffithii or A. fargesii.

Our Seed Germinating Experience

Seeds earn an intermediate rating because its dormancy behavior depends on freshness. Arisaema seed is not recalcitrant – they can dry out, but behave differently when fresh versus stored. Fresh seed often germinates warm without any cold period, while stored or dried seed frequently requires moist cold stratification to break dormancy. This places the species in the “short‑lived to sub‑recalcitrant” category: tolerant of drying, but with a shift in dormancy once dry.

Our batch of A. tortuosum seed had an unknown storage history, so we sowed it immediately into moist medium at 4 °C. Germination began five months later, still in the cold phase. Once moved to room temperature, germination accelerated dramatically: about 90% of the seed germinated within two weeks.

Fresh seed, by contrast, often germinates in 4–8 weeks under warm, bright, evenly moist conditions without any cold period. Both pathways are reliable, but stored seed nearly always benefits from cold.

Seed‑grown A. tortuosum is not fast to mature, but it rewards patience. Expect flowering‑sized corms in approximately 3–5 years, depending on growing conditions and how long you can keep the young plants actively growing before dormancy.

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Billardiera longiflora

Skill Level: Intermediate to Advanced

Billardiera longiflora, known as Climbing Blueberry or Purple Appleberry, is an elegant, twining evergreen vine native to Tasmania and southeastern Australia. In the garden it thrives in humus rich, neutral to acidic, lime free soils and appreciates consistent moisture with excellent drainage. It grows happily in partial shade to morning sun—conditions very much like a cool, coastal forest edge—making it well suited to sheltered sites in coastal British Columbia. Hardy roughly to USDA Zone 8–9, it reaches 2–3 m and produces narrow, bell shaped flowers that open pale chartreuse, age through creamy white, and finally blush lavender purple. By autumn, clusters of glossy violet 2.5cm berries hang among the dark green foliage, giving the plant a quietly exotic presence. Slow to establish, but definitely worth the wait.

Our Seed Germination Experience

Seed germination is slow and irregular, and patience is essential. Seeds are relatively short-lived, with germination rates reducing considerably after 12 months. Seeds can be sown at any time, covered lightly, and kept at 15–20 °C. Some sites suggest germination may take place under these conditions within 2-6 months, but this is not our experience. After six months at room temperature, germination required a further 2 months at 3–5 °C with radicles appearing while in cold stratification. Once germinated, seeds are grown on at 15–20 °C.

#evergreenvines#SeedGermination#GrowFromSeed#UnusualPlants#PlantPropagation#vines#SeedStarting#NativePlants#ShadeGarden#Stratification#Billardiera

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Cyclamen cyprium

Skill Level: Beginner – Intermediate

Cyclamen cyprium, the national flower of Cyprus, is a graceful autumn blooming species adapted to the island’s rocky, Mediterranean woodlands. In the wild it survives hot, bone dry summers tucked into crevices and limestone ledges, then awakens with the first autumn rains to grow in the cool, humus-rich leaf litter that accumulates in the cracks. This seasonal rhythm makes it exceptionally well suited to a drier, shady corner of the garden, where many plants struggle. Its marbled foliage emerges in early autumn, followed by soft pink, lightly scented flowers from October into November. Growth continues through winter and early spring before the plant retreats into its summer dormancy, during which dryness is essential. Hardy to roughly USDA Zone 7, it thrives in containers, troughs, and woodland beds where its subtle beauty can be appreciated.

Our Seed Germinating Experience

Seed germination is straightforward and ideal for beginners. Store dry seeds in the fridge for no longer than 6 months from harvest as germination rates reduce noticeably if kept longer. We have found soaking unnecessary. Sow at any time, covered lightly, and kept at ordinary room temperature, where they typically germinate in 4–6 weeks. Above all, excellent drainage is critical—both for seedlings and mature plants—mirroring the porous, rocky soils of its native habitat. Once established, Cyclamen cyprium is remarkably resilient, provided it receives moisture in winter and a reliably dry rest in summer.

Photo from cyclamen.org

#Cyclamen#SeedGermination#GrowFromSeed#MediterraneanPlants#PlantPropagation#SeedStarting#WoodlandGarden#AutumnBloomers

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Bukiniczia cabulica

Skill Level: Beginner

Bukiniczia cabulica, sometimes called the Afghan Pink or simply Bukiniczia, is a striking rosette forming member of the bellflower family native to rocky, sun washed slopes of Afghanistan and Pakistan. Its low, architectural whorl of silver green, lanceolate leaves looks almost sculptural, and in its second or third year it sends up a tall, airy spire of soft pinkish, starry flowers that hover above the foliage like a cloud of confetti. As a monocarpic species, each rosette flowers once and then dies, but it often self sows lightly in well drained, gritty soil, allowing the plant to persist in the garden with minimal effort. Perfect for troughs, crevice gardens, and dry borders, it thrives in full sun and lean conditions, echoing the rugged alpine habitats it comes from.

Our Seed Germination Experience

Seed germination is refreshingly straightforward—ideal for beginners. Seeds can be sown at any time, covered very lightly, and kept at ordinary room temperature, where they typically germinate in about 7 days. Once seedlings appear, they grow on happily in bright light with careful watering and excellent drainage.

Photo: Garden.org

#rockgarden #SeedGermination #GrowFromSeed #UnusualPlants #PlantPropagation #SeedStarting#AlpinePlants #Monocarpic