Plectocephalus Species, Mexican Basket Flower, Madrean Starthistle, Rothrock's Knapweed

Plectocephalusrothrockii

Family
Asteraceae (ass-ter-AY-see-ee)
Species
rothrockii (roth-ROK-ee-eye)
Synonym
Centaurea rothrockii
Sun Exposure
Full Sun
Sun to Partial Shade
Light Shade
Foliage
Herbaceous
Succulent
Height
12-18 in. (30-45 cm)
18-24 in. (45-60 cm)
Spacing
12-15 in. (30-38 cm)
Hardiness
USDA Zone 3a: to -39.9 °C (-40 °F)
USDA Zone 3b: to -37.2 °C (-35 °F)
USDA Zone 4a: to -34.4 °C (-30 °F)
USDA Zone 4b: to -31.6 °C (-25 °F)
USDA Zone 5a: to -28.8 °C (-20 °F)
USDA Zone 5b: to -26.1 °C (-15 °F)
USDA Zone 6a: to -23.3 °C (-10 °F)
USDA Zone 6b: to -20.5 °C (-5 °F)
USDA Zone 7a: to -17.7 °C (0 °F)
USDA Zone 7b: to -14.9 °C (5 °F)
USDA Zone 8a: to -12.2 °C (10 °F)
USDA Zone 8b: to -9.4 °C (15 °F)
Danger
N/A
Bloom Color
Pale Yellow
Medium Purple
Bloom Time
Late Spring/Early Summer
Mid Summer
Other Details
Category
Perennials
Water Requirements
Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not overwater
Foliage Color
Blue-Green
Where to Grow
Bloom Characteristics
This plant is attractive to bees, butterflies and/or birds
Bloom Size
Other details
Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)
Patent Information
Propagation Methods
By dividing the rootball
From seed; direct sow after last frost
Self-sows freely; deadhead if you do not want volunteer seedlings next season
Seed Collecting
Allow seedheads to dry on plants; remove and collect seeds
Regional

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Gardener's Notes:

0
positive
0
neutral
0
negative
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(Sclerocyphon sp.)
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Featured
Water Penny
(Sclerocyphon sp.)
Sacred Kingfisher
(Todiramphus sanctus)