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Light Needs
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Mature Height
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Mature Spread
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Growing Zones
- Partial Sun to Full Sun (At Least 5 Hours of Direct Sunlight)
- Mature Height 18 - 22 Inches
- Mature Spread 18 - 22 Inches
- Growing Zones 4 - 9
- Use As A Thriller In Containers
Boasting a light blue flower atop dark green threadleaf foliage, this late spring to early summer flowering perennial will provide color and soft texture to your garden. In the fall, the foliage will turn from dark green to a brilliant orange. It can grow to a compact height of up to 22” and a spread of up to 36”. This easy to maintain plant will be an excellent addition to any garden.
Native to North America, this perennial is deer resistant and tolerant to moderate heat and humidity. Compact growth habits will create a visual appeal without too much pruning or shaping. Does great in mass planting, border planting and overall landscaping. Providing a splash of color and texture that will complement other flowers and foliage, it does great as a cut flower in floral arrangements. This plant thrives in average soil without much care, nor attention.
String Theory Amsonia Care
Planting in either poor or average quality soil will render the best results within the foliage and flowers, alike. A neutral pH of 7.0 is recommended for the soil for best results. It Is best planted in either partial or full sun. If the soil is too fertile or in too much shade, the compact habit is less likely to continue as the plant loses its shape by becoming droopy. Consistent watering is best for maintaining moist soil, but do be careful not to overwater.
After flowering, cut the stems down to about 6”-8” from the ground to encourage prolific flowering for the next spring. The growth habits of this plant provide you with peace of mind that you will not need to be endlessly dividing the individual plants to create space for new growth. After several years, plant division is recommended to maintain a healthy root system.
String Theory Amsonia Spacing
This is a compact, medium sized perennial that does well planted on its own or as a border plant. Growing up to 36” wide, the plant spacing is recommended to be 32”-36” on center.
String Theory Amsonia Information
USDA Hardiness Zones: 4 - 9 |
Plant Type: Bushes |
Light Exposure: Partial Sun to Full Sun (At Least 5 Hours of Direct Sunlight) |
Mature Height: 18 - 22 Inches |
Mature Spread: 3 Feet |
Spacing: 3 Feet |
Habit: Mounded |
Flower Color(s): Blue |
Flower Description: Light Periwinkle Blue |
Bloom Period: Early Summer To Late Spring |
Foliage Type: Deciduous, Herbaceous |
Foliage Color(s): Green |
Foliage Description: Dark green |
Seasonal Interest: Spring Flowering, Summer Flowering |
Watering: Average |
Resists: Deer |
Tolerates: Heat |
Attracts: N/A |
Container Role: Thriller |
Uses: Borders, Containers, Mass Planting, Specimen or Focal Point, Wildlife Gardens |
Features: Low Maintenance, Native to North America |
Brand: Proven Winners |
Common Name: String Theory Amsonia |
Other Name(s): Bluestar |
Scientific Name: Amsonia hybrid USPPAF, Can PBRAF |
- SKU:
- AMSTY
Container Sizes
Please Note: The pictures below are to give a general representation of the different container sizes. The actual size/ages of plants are estimates and will vary based on type of plant, time of year, last pruning & many other factors.
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Quart Pot
Also Known As:
Quart
Plant Age:
~ 6 months - 1 year
Plant Size:
~ 4"-8"
Pot Size:
~ 4.75"H x 4.5"W
Volume:
1.50 quarts
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2.5 Quart
Also Known As:
2.5 Quart Pot
Plant Age:
~ 1 - 2 years old
Plant Size:
~ 8"-12"
Pot Size:
~ 6.5"H x 6.5"W
Volume:
2.20-2.30 quarts
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#1 Pot
Also Known As:
#1 Container
1 Gallon
Plant Age:
~ 1 - 2 years old
Plant Size:
~ 10"-14"
Pot Size:
~ 7"H x 7.75"W
Volume:
2.26-3.73 quarts
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#2 Pot
Also Known As:
#2 Container
2 Gallon
Plant Age:
~ 1.5 - 3 years old
Plant Size:
~ 12"-18"
Pot Size:
~ 9.5"H x 9.5"W
Volume:
1.19-1.76 gallons
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#3 Pot
Also Known As:
#3 Container
3 Gallon
Plant Age:
~ 2 - 4 years old
Plant Size:
~ 12"-30"
Pot Size:
~9.5"H x 11"W
Volume:
2.32-2.76 gallons
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#5 Pot
Also Known As:
#5 Container
5 Gallon
Plant Age:
~3-4 years old
Plant Size:
~ 20" - 60"
Pot Size:
~11" H x 10 1/2” W
Volume:
3.5 - 4 gallons
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Best in Class Warranty
We stand behind our plants with industry-leading guarantees to give you peace of mind.
Arrival Guarantee
We want your plants to arrive in great condition! If you notice any issues upon delivery, contact us within 3 days.
Free 1-Year Plant Warranty
All bushes, perennials & trees come with an extended 1-year warranty for added confidence. If your plant dies due to a health issue within a year, we’ll make it right.
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Pre-Ordered Plants
Pre-ordered plants are scheduled to ship in Spring 2025. We carefully plan our shipping dates based on your USDA Plant Hardiness Zone to ensure optimal planting conditions upon arrival. Want it sooner/later? Reach out, and we'll try our best to accommodate.
Estimated Spring Shipping Schedule
Estimated ship week for pre-ordered plants will ship based on growing zones as shown below.
Growing Zone | Estimated Ship Week |
---|---|
Zone 10 | March 24th |
Zone 9 | March 31st |
Zone 8 | April 7th |
Zone 7 | April 14th |
Zone 6b | April 21st |
Zone 6a | April 28th |
Zone 5b | May 5th |
Zone 5a | May 12th |
Zone 4 | May 19th |
Zone 3 | May 26th |
Note: These are only estimated ship dates. Plants may ship out later depending on weather & growing conditions of the plant.
Note: Only plants indicated as pre-order will ship as shown above. All other plants and hard goods will ship as normal.
Plants Shipping Now
Plants that are currently in stock typically ship within 2-7 business days after your order is placed.