Evolvulus alsinoides
tropical speedwell
Pantropical, including northern Australia
Overview
Evolvulus alsinoides is a small, spreading perennial herb of the morning-glory family, forming low mats 4-12 inches (10-30 cm) high and trailing 8-20 inches (20-50 cm) across on slender, softly hairy stems. The small narrow leaves are 0.2-1 inch (0.5-2.5 cm) long, grey-green, and clothed in silky hairs. Unlike its climbing relatives, it does not twine; instead the stems creep and ascend. Small flat flowers about 0.3-0.4 inch (8-10 mm) across open along the stems, clear blue with a paler center, lasting a single day and replaced over a long warm-season period. Native across the tropics, including northern Australia, Asia, Africa, and the Americas, it grows in open grassland, rocky slopes, and disturbed ground in full sun. It tolerates heat, drought, and poor soil but is frost-tender and behaves as an annual where winters are cold. The blue flowers close by afternoon and in dull weather, so the display is strongest in morning sun. Growth is quick, and plants flower within the first season. It is used in traditional herbal medicine in parts of its range.
Native Range
Native across the tropics and subtropics, including northern Australia, southern Asia, Africa, and the warmer Americas. It grows in open grassland, rocky slopes, and disturbed sunny ground.Suggested Uses
Used as a low groundcover, in rockeries, containers, and hanging baskets in sunny, well-drained sites. Suited to low-water and coastal gardens, spaced 10-14 inches (25-35 cm) apart for cover.How to Identify
Appearance
Size & Dimensions
Height4" - 1'
Width/Spread8" - 1'8"
Reaches mature size in approximately 1 years
Bloom Information
Clear blue flowers open over a long warm-season period, mainly spring through autumn and much of the year in frost-free climates. Each flat flower lasts only one day and closes by afternoon, replaced by new buds. Flowering is heaviest in full morning sun.
Detailed Descriptions
Foliage Description
Grey-greenGrowing Conditions
Sun Requirements
Requires 7-11 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grows in full sun on free-draining sandy, loamy, or rocky soils and tolerates heat and drought once established. Water needs are low, and excess moisture or shade reduces flowering and weakens the stems. It grows well in poor soil and needs little or no feeding. The plant is frost-tender and grows as a perennial in warm climates or an annual where winters are cold. In containers it suits a free-draining mix with moderate water. Light trimming keeps the spreading habit compact.Pruning
A light trim through the growing season keeps the mat dense and tidy. Cutting back leggy stems encourages fresh growth and more flowers. No heavy pruning is needed on this low herb.Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons