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Houstonia caerulea - L.

Common Name Azure bluet or Quaker ladies
Family Rubiaceae
USDA hardiness 3-8
Known Hazards None Known
Habitats Fields and open woods on moist acidic soils in shady areas, growing especially well among grasses.
Range Native to eastern Canada (Ontario to Newfoundland) and the eastern United States (Maine to Wisconsin, south to Florida and Louisiana, with scattered populations in Oklahoma).
Edibility Rating    (2 of 5)
Other Uses    (3 of 5)
Weed Potential No
Medicinal Rating    (0 of 5)
Care (info)
Fully Hardy Well drained soil Moist Soil Semi-shade Full sun
Houstonia caerulea Azure bluet or Quaker ladies

Houstonia caerulea Azure bluet or Quaker ladies
Jomegat wikimedia.org


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Physical Characteristics

 icon of manicon of flower
Houstonia caerulea is a PERENNIAL growing to 0.1 m (0ft 4in) by 0.1 m (0ft 4in) at a fast rate.
See above for USDA hardiness. It is hardy to UK zone 4.
It is noted for attracting wildlife.
Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid and neutral soils and can grow in very acid soils.
It can grow in semi-shade (light woodland) or no shade. It prefers dry or moist soil.

UK Hardiness Map US Hardiness Map


Anotis coerulea (L.) G.Don. Anotis gentianoides (Endl.) Walp. Hedyotis brachiata Miq. ex Hook.f. Hedyotis caerulea (L.) Hook. Hedyotis caerulea f. albiflora (Millsp.) Fosberg. Hedyotis caerulea f. benkei Fosberg. Hedyotis caerulea var. faxonorum (Pease & A.H.Moore) Fosberg. Hedyotis gentianoides Endl. H. caerulea f. albiflora Millsp. H. caerulea f. caerulea. H. caerulea var. caerulea. H. caerulea var. elatior (Michx.) Pursh. H. caerulea var. faxonorum Pease & A.H.Moore. H. caerulea var. piersii Barbour. H. caerulea var. toxonorum Stevens. H. faxonorum (Pease & A.H.Moore) Fernald. H. grandiflora Raf. H. linnaei Michx. H. linnaei var. elatior Michx. Oldenlandia caerulea (L.) A.Gray. Poiretia erecta J.F.Gmel.

Plant Habitats

Edible Uses

Edible Parts: Flowers  Leaves
Edible Uses:

Raw; Leaves. Flowers in salads. No further information found.

References   More on Edible Uses

Medicinal Uses

Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.

None known

References   More on Medicinal Uses

The Bookshop: Edible Plant Books

Our Latest books on Perennial Plants For Food Forests and Permaculture Gardens in paperback or digital formats.

Food Forest Plants for Hotter Conditions: 250+ Plants For Tropical Food Forests & Permaculture Gardens.
Edible Tropical Plants

Food Forest Plants for Hotter Conditions: 250+ Plants For Tropical Food Forests & Permaculture Gardens.

Plants for Your Food Forest: 500 Plants for Temperate Food Forests & Permaculture Gardens.
Edible Temperate Plants

Plants for Your Food Forest: 500 Plants for Temperate Food Forests & Permaculture Gardens.

PFAF have eight books available in paperback and digital media.
More Books

PFAF have eight books available in paperback and digital formats. Browse the shop for more information.

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Other Uses

Groundcover. This plant is attractive to bees, butterflies and/or birds. Uses: Alpine & Rock gardens, Containers, Edging, Waterside, Wild Flower, Woodland.

Special Uses

Food Forest  Ground Cover

References   More on Other Uses

Cultivation details

A low creeping mat of tiny green leaves. Prefers evenly moist soil and acidic conditions. Full Sun or Partial Shade. Soil Type: Normal to Clay. Soil pH: Neutral to Acid.

References   Carbon Farming Information and Carbon Sequestration Information

Temperature Converter

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The PFAF Bookshop

Plants For A Future have a number of books available in paperback and digital form. Book titles include Edible Plants, Edible Perennials, Edible Trees,Edible Shrubs, Woodland Gardening, and Temperate Food Forest Plants. Our new book is Food Forest Plants For Hotter Conditions (Tropical and Sub-Tropical).

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Plant Propagation

Seed or division. Divide the rootball. Seed - Direct sow as soon as the ground can be worked in spring. Seed Collecting: Collect seedhead/pod when flowers fade; allow to dry.

Other Names

If available other names are mentioned here

Azure bluet, Quaker ladies, little bluet

NORTHERN AMERICA: Canada, Québec (south), Nova Scotia, Ontario (south), United States, Connecticut, Indiana, Maine, Massachusetts, Michigan (south), New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, Vermont, West Virginia, Illinois, Iowa (east), Missouri (southeast), Wisconsin, Alabama, Arkansas, Delaware, Georgia, Kentucky, Louisiana (north), Maryland, Mississippi (northeast), North Carolina, South Carolina, Tennessee, Virginia,

Weed Potential

Right plant wrong place. We are currently updating this section. Please note that a plant may be invasive in one area but may not in your area so it’s worth checking.

None Known

Conservation Status

IUCN Red List of Threatened Plants Status :

Related Plants
Latin NameCommon NameHabitHeightHardinessGrowthSoilShadeMoistureEdibleMedicinalOther
Ageratum houstonianumAgeratum, Bluemink, Floss Flower, GardenAnnual0.3 0-0 MLMHNDM01 

Growth: S = slow M = medium F = fast. Soil: L = light (sandy) M = medium H = heavy (clay). pH: A = acid N = neutral B = basic (alkaline). Shade: F = full shade S = semi-shade N = no shade. Moisture: D = dry M = Moist We = wet Wa = water.


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Botanical References

Links / References

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Subject : Houstonia caerulea  
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