Trachelium Caeruleum Lake Forest Purple

Trachelium Caeruleum Lake Forest Purple Seeds

(Professional Cut Flower — Dark Purple)

Trachelium caeruleum, commonly known as Throatwort, is one of the most valued specialty cut flowers in the professional floristry trade — a member of the Campanulaceae family producing distinctive dome-shaped umbels densely packed with hundreds of tiny star-shaped florets. Lake Forest Purple from PanAmerican Seed’s Lake Collection is a deep, sparkling dark purple variety that delivers outstanding stem quality, excellent vase life averaging 11 days, that have made the Lake Collection the benchmark range for professional cut flower production worldwide.

The Lake Collection produces a large central umbel with smaller side umbels or “satellites” that surround it, creating a multi-layered flower head of exceptional visual richness and texture. The dark purple coloration of Lake Forest Purple is particularly valuable in floral design — deep, cool-toned purple provides contrast and depth in mixed arrangements, works well with whites, soft pinks, and lavenders, and gives a rich, luxurious character to wedding, event, and bouquet work.

The flowers are excellent fillers in arrangements alongside lisianthus, roses, snapdragons, and other cut flowers, where Trachelium’s cloud-like texture provides a counterpoint to the bold forms of larger blooms. The stems are stiff, erect, and do not require support in the vase. Flowers should be harvested when one quarter to half of the florets are open for the longest vase life, and stems can last up to two weeks in clean water.

Trachelium has very small seeds that need to be pelleted to be visible, and seedling growth is slow, requiring 10–12 weeks from sowing to transplanting. Seeds should be sown on the soil surface since light is required for germination.

Variety Details

• Variety: Lake Forest Purple
• Series: Lake Collection
• Breeder: PanAmerican Seed
• Flower color: Sparkling dark purple
• Flower form: Large central dome umbel with satellite side umbels
• Stem height: Approximately 75 cm
• Vase life: Average 11–14 days in clean water
• Season: Winter-flowering variety — transplant autumn to early winter for mid-winter to early spring flowers

Key Features

• Professional cut flower variety from PanAmerican Seed’s Lake Collection.
• Large sparkling dark purple dome-shaped umbels with satellite clusters.
• Stem height approximately 75 cm — excellent for bouquets and arrangements.
• Average vase life 11–14 days in clean water.
• Stiff, erect stems — no support required in the vase.
• Pairs beautifully with lisianthus, roses, snapdragons, and soft-toned flowers.

Plant Information

• Height: Approximately 75 cm
• Spread: 20–25 cm
• Plant type: Half-hardy annual (short-lived perennial in frost-free zones)
• Light requirement for flowering
• Sun: Full sun to partial shade
• Soil: Fertile, well-drained soil, pH 6.0–7.0
• Water: Consistent moisture — sensitive to high salts at germination
• Spacing: 25–30 cm apart

Seed Germination

• Seed depth: Surface sow — do NOT cover; seeds require light to germinate
• Germination time: 10–30 days
• Ideal germination temperature: 20–22°C
• Important notes: Trachelium seeds are very small and come pelleted for easier handling. Surface sow on moist, fine seed-starting compost at 20–22°C and keep continuously moist.
• Do not cover seeds as light is essential for germination.
• Trachelium is sensitive to high salt levels — do not fertilize during germination.
• Seedling growth is slow — allow 10–12 weeks from sowing to transplant-ready size.

Growing Tips

• Sow Lake Forest Purple seeds on the surface of a fine, moist, sterile seed-starting compost at 20–22°C.
• Do not cover seeds. Water gently by misting or sub-irrigation to avoid disturbing the tiny, pelleted seeds.
• Keep continuously moist and maintain good light throughout germination.
• Germination takes 10–30 days and seedling growth thereafter is slow — patience and consistent care are essential.
• Once seedlings reach transplant size after 10–12 weeks, move into individual 7.5 cm pots and grow on under bright light.
• Space final plants 25–30 cm apart in well-drained, fertile soil or growing medium.
• Harvest stems when half or more of the florets are open for best vase life.
• For cut flower use, pinch or cut the central stem after first harvest to encourage side-shoot development and additional stem production.

Gulf Growing Notes

• Trachelium thrives in cool to mild temperatures — the Gulf cool season from November to April provides ideal growing temperatures.
• Recommended approach for Gulf growers: Sow seeds in August–September indoors.
• Grow seedlings under supplemental lighting. Transplant in October–November.

Floral Design Uses

• Cut flower filler and texture in mixed bouquets
• Wedding and event floristry
• Arrangements with lisianthus, roses, snapdragons, and soft-toned flowers
• Long-life stems for retail and fresh market cut flower supply
• Dried flower arrangements — retains color well when dried