The Story
Plant Bio
Lobelia x hybrida 'Grape Knee-Hi' is a compact, bushy perennial with vibrant, trailing stems adorned with small, tubular, violet-blue flowers. Its lush foliage is green and slightly serrated.
This cultivar is prized for its vigorous trailing habit and rich color, making it ideal for hanging baskets and containers with a long flowering period.
Uses & Benefits:
Essentials
At a Glance
Plant Type
Perennial
Height
6 inches
Width
12 inches
Light
Full Sun, Partial Sun, Shade
Zones
4, 5, 6, 7, 8, 9
Water
Regular moisture, avoid drought
Humidity
Average
Lifespan
Perennial
Native To
North America
Toxicity
Non-toxic to humans and pets
Bloom period
Mid-summer – Late summer
In flower about 2 months of the year
Planting
How to Grow
- Tuck seeds into moist soil in early spring.
- Keep soil consistently moist during the growing season.
- Provide partial shade in hot climates for optimal growth.
- Use organic compost to enrich soil before planting.
- Water regularly to maintain soil moisture, especially in dry periods.
- Pinch back to encourage bushier growth and more flowers.
Pro Tip
Maintain evenly moist soil and provide partial shade for best flowering.
Keep It Thriving
Care Guide
Do
- Water regularly to keep soil moist 🌱
- Pinch back to promote bushier growth
- Apply organic mulch to retain moisture
Don't
- Allow soil to dry out completely ❌
- Over-fertilize, which can reduce flowering
- Expose to full harsh sun in very hot climates ❌
Seasonal Care Calendar
| Task | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Fertilize | ||||||||||||
| Pest Check | ||||||||||||
| Prune |
Watch Out For
Pests & Diseases
Common Pests
Common Diseases
In the Garden
Landscape Uses & Companions
Landscape Uses
Companion Plants
Multiply
Propagation Methods
Good to Know
Common Questions
Grape Knee-Hi Lobelia questions
What zones can Grape Knee-Hi Lobelia grow in?
Grape Knee-Hi Lobelia is hardy in USDA Zones 4–9. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.
Is Grape Knee-Hi Lobelia deer resistant?
Not reliably. Deer may browse Grape Knee-Hi Lobelia, especially tender spring growth — plan on repellents or fencing where pressure is high.
When does Grape Knee-Hi Lobelia bloom?
Grape Knee-Hi Lobelia typically blooms in mid-summer through late summer. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.
Does Grape Knee-Hi Lobelia need full sun?
Grape Knee-Hi Lobelia does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.
More Lobelia to compare
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Lobelia cardinalis
Hybrid Cardinal Flower
Lobelia speciosa 'Compliment Violet'
Lilac Candles Great Blue Lobelia
Lobelia siphilitica 'Lilac Candles'
Cardinal Flower 'Black Truffle'
Lobelia cardinalis 'Black Truffle'
Fan Cinnabar Rose Lobelia
Lobelia speciosa 'Fan Cinnabar Rose'
Perrys White Cardinal Flower
Lobelia cardinalis 'Perrys White'
Keep exploring
Explore the genus
Grow Grape Knee-Hi Lobelia with confidence
See it in a design of your actual yard, get zone-matched care reminders, and track it season by season in your garden journal.