Great Blue Lobelia
Lobelia siphilitica
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Great Blue Lobelia - #1 Container is backordered and will ship as soon as it is back in stock.
Plant Sentry™
Plant Sentry™
Plant Sentry is designed to protect both consumers and the nursery trade from invasive plant pests and diseases. Sites that display the Plant Sentry protection badge are protected from consumers buying and nurseries shipping material carrying invasive pests and diseases.
This proprietary eCommerce software prevents the shipment of a restricted plant to each state. The Plant Sentry system includes a shipment certification program. The Plant Sentry Compliance Officer works closely with NatureHills.com and each nursery or fulfillment center to ensure only compliant plants are sold to customers.
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Delivery and Shipping
Delivery and Shipping
Shipping
To obtain a more accurate shipment time-frame, simply enter your zip code in the “Find Your Growing Zone” box to the right. Our plants are grown all over the country and lead time on items may be different because of this. Once your order is placed, you will also receive the specific shipment time-frame information as part of your order confirmation. Once an item ships, you will receive shipment notification and tracking numbers, so you can follow along while your plant travels to your doorstep. We use FedEx, UPS, or USPS at our discretion.
Due to winter weather we have put a hold on shipping to the areas shown below in grey. You can still order now and we will ship the plant to you during an appropriate time for your zone.
Standard Shipping Rates
At Nature Hills we handle, package and ship the products you order with the utmost care to ensure healthy delivery. Shipping and handling charges are calculated based on the tables below. Please note that some items include an additional handling surcharge, these will be noted on the item's product page.
From | To | S&H |
---|---|---|
$0 | $19.99 | $24.99 |
$20 | $49.99 | $29.99 |
$50 | $69.99 | $34.99 |
$70 | $99.99 | $39.99 |
$100 | $129.99 | $44.99 |
$130 | $149.99 | $48.99 |
$150 | $150+ | Approx 28% |
Click here to see our full rates
Understanding Plant Options
Nature Hills offers plants in two main formats:
- Container Plants: Grown in pots with soil, sized by container volume and plant age
- Bare Root Plants: Dormant plants without soil, sized by height measurements
Container Plant Sizes
Container sizes indicate plant age and growing capacity rather than liquid volume equivalents. Our containers follow industry-standard nursery "trade gallon" specifications, which differ from standard liquid gallon measurements.
Young Plants (6 months to 18 months old)
Container Size | Actual Volume | Metric Equivalent |
---|---|---|
2" x 2" x 3" | 0.18 - 0.21 dry quarts | 0.20 - 0.23 dry liters |
4" Container | 0.31 - 0.87 dry quarts | 0.35 - 0.96 dry liters |
4.5" Container | 0.65 dry quarts | 0.72 dry liters |
6" Container | 1.4 dry quarts | 1.59 dry liters |
1 Quart | 1 dry quart | 1.1 dry liters |
5.5" Container | 1.89 dry quarts | 2.08 dry liters |
Established Plants (18 months to 2.5 years old)
Container Size | Actual Volume | Metric Equivalent |
---|---|---|
2 Quart | 2 dry quarts | 2.2 dry liters |
#1 Container | 2.26 - 3.73 dry quarts | 2.49 - 4.11 dry liters |
5" x 5" x 12" | 3.5 - 4.3 dry quarts | 3.85 - 4.74 dry liters |
Mature Plants (2-4 years old)
Container Size | Actual Volume | Metric Equivalent |
---|---|---|
#2 Container | 1.19 - 1.76 dry gallons | 5.24 - 7.75 dry liters |
#3 Container | 2.15 - 2.76 dry gallons | 8.14 - 12.16 dry liters |
Large Plants (3-5 years old)
Container Size | Actual Volume | Metric Equivalent |
---|---|---|
#5 Container | 2.92 - 4.62 dry gallons | 12.86 - 20.35 dry liters |
#6 Container | 5.25 - 6.01 dry gallons | 23.12 - 26.42 dry liters |
#7 Container | 5.98 - 6.53 dry gallons | 26.34 - 28.76 dry liters |
Bare Root Plants
Bare root plants are sold by height from the root system to the top of the plant. Plants may exceed minimum height requirements.
Common Sizes:
- Trees: 1 foot, 2 feet, 3 feet, 4 feet, 5 feet, 6 feet
- Shrubs & Perennials: 1 foot, 18 inches, 2 feet
Important Notes
Container Volume Specifications
- Trade Gallon Standard: Our containers follow industry-standard "trade gallon" specifications established by the American National Standards Institute (ANSI Z60.1) for nursery stock
- Volume Variations: Actual soil volume may vary due to plant root systems and growing medium settlement
- Age Indicators: Container size primarily indicates plant age and maturity rather than liquid volume equivalents
Growing Conditions
- Plant size can vary based on variety and growing conditions
- Container size helps indicate plant maturity and establishment level
- Larger containers generally mean more established root systems and faster landscape establishment
Seasonal Availability
- Bare root plants are available seasonally when dormant
- Container plants are available throughout the growing season
- Specific varieties may have limited availability in certain sizes
Questions?
For questions about specific plant sizes or availability, please contact our plant experts who can help you choose the right size for your landscape needs.
Plant Highlights
Great Blue Lobelia highlights at a glance!
Specifications
Specifications
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Brand
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Botanical Name
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Growing Zones
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Mature Height
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Mature Spread
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Sun ExposureFull Sun
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Moisture
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Soil
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Growth RateMedium
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Flower Color
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Pollinator Friendly
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Fragrant
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Pruning Time
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Bloom PeriodLate Spring, Summer, Fall

Growing Zones 4-9
Need a gorgeous blue flowering perennial that handles wet to very moist soil? The Great Blue Lobelia (Lobelia siphilitica) is a hardy Cardinal Flower bearing tall, leafy spikes of clear blue flowers. Members of the Bellflower Family, this showy perennial can be branched or unbranched, which you can encourage with pruning if you want more flowers, versus one large towering spire!
Great Blue is a clump-forming perennial with upright leafy stems. It blooms from late summer to mid-autumn and bears dense spikes of light to bright blue, but can sometimes be lavender or purplish because of their wide native genetic variability. Forming many tubular, two-lipped flowers with a more prominent lower lip. These are wonderfully long-lasting because they flower from the bottom to the top!
Great Blue will attract a plethora of curious butterflies to their nectar resources and the tubular flowers might even have a Hummingbird visitor or two! Perennial throughout USDA planting zones 4 to 9, this wetland native plant features mounds of lance-shaped green leaves with tall wands of dramatic flowering spikes rising high above them.
Planting and Application:
These spikes make it the perfect back-of-the-border plant in your perennial flower beds, Cottage gardens, and Rain Gardens! This perky perennial was made for your backyard pollinator gardens! Create groupings in water gardens or pond edges to draw the eye and give beneficial insects, like dragonflies, a place to land as they search for more pesky prey, like mosquitoes. This will make your outdoor enjoyment even better without these pests!
Of course, this Blue Cardinal Flower can also be used near the back of your property to soften the moist woodland edges or used at the base of a water feature you've installed. No matter where you plant Great Blue, it'll look absolutely stunning!
The tall flower spikes can be clipped and bright indoors to complete a delightful bouquet. Place them in the kitchen or on the living room coffee table to freshen up your space. By snipping a few blooms, you'll encourage more to rebloom throughout the growing season!
- Tall Spikes of Blue to Purple Florets
- Long-Lasting Blooms Until Mid-Autumn
- Lush Green Lance-Shaped Foliage
- Wetland Native Perennial
- Great For Pollinators, Hummingbirds & Cut Flowers
- Tall Specimens, Groupings, Back-of-the-Border, Water Gardens & Rain Gardens
#ProPlantTips for Care:
This full-sun perennial grows 2-3 feet tall, so 6 hours of direct sunlight is needed to maintain strong upright flowering stems. The Blue Cardinal Flower prefers deep, moist soil and should be fertilized every two weeks in spring and early summer to improve flowering.
Pinching back young plants encourages branching, or pinch back offshoots to encourage a single large flower per plant. These herbaceous Perennials may be trimmed as they die back in hot summers. Deadhead to encourage new blooms, and clean the mounds up in the early spring before the growing season begins.
- Full Sun Perennials
- Almost Any Soil That Isn't Stagnant
- Moist to Wetland Conditions
- Pinch Back, Deadhead In Summer & Prune In Spring
- Deer & Rabbits Seldom Bother These
The beautiful blue cousin to the red Cardinal Flower is a refreshing native perennial to enliven your landscape with its unique color and form! Order the Great Blue Lobelia today at Nature Hills, and go native!