Evolvulus alsinoides (tropical speedwell)

1 / 3

Evolvulus spp.

dwarf morning glory

Convolvulaceae

Tropical and subtropical Americas (some species pantropical)

Attracts Pollinators Attracts Butterflies Drought Tolerant Container Friendly

Native to North America

SunFull Sun

WaterLow · drought-tolerant

HardinessZones 8–11

Overview

Evolvulus spp. is a genus of about 100 herbs and subshrubs in the morning glory family, Convolvulaceae, found mainly in the warmer parts of the Americas, with some species spread across the tropics. Unlike most of its twining relatives, Evolvulus spp. does not climb; instead it forms low, spreading mats or mounds 6-18 inches (15-45 cm) tall and up to 3 feet (90 cm) across. The small leaves are often silvery with silky hairs, and the funnel-shaped flowers, about 0.5-1 inch (1-2.5 cm) wide, open flat in clear blue, lavender, or white. Each flower lasts a single day, opening in morning sun and closing by afternoon, but plants bloom steadily through warm weather. E. glomeratus, sold as blue daze, is widely grown as a heat-tolerant bedding and container plant, while E. alsinoides is used in traditional medicine across its pantropical range. Plants are frost tender and are grown as annuals where winters are cold. Growth is fast, but the stems can become bare at the base over time.

Native Range

Mainly the tropical and subtropical Americas, with the greatest number of species in Central and South America. A few species, such as E. alsinoides, are spread across the tropics of Africa, Asia, and Australia.

Suggested Uses

Evolvulus spp. is grown as a low bedding plant, edging, ground cover, and spiller in containers and hanging baskets, where its blue flowers and silvery foliage trail over the sides. Its heat and drought tolerance suit it to hot borders and coastal gardens. E. alsinoides is grown as a medicinal herb in parts of its range.

How to Identify

Recognized by low, non-climbing, spreading stems clothed in small, often silvery, silky-haired leaves and by round, funnel-shaped flowers in clear blue that open flat in the morning sun. The lack of twining separates Evolvulus spp. from true morning glories and bindweeds. Flowers close by afternoon and on cloudy days.

Appearance

Size & Dimensions

Height6" - 1'6"

Width/Spread1' - 3'

Colors

Flower Colors

Foliage Colors

Bloom Information

Bloom Period

~20 weeks

Spring Summer Fall

Plants bloom steadily from late spring through autumn in warm conditions, and year-round in frost-free climates. Each blue flower opens in the morning and closes by mid-afternoon, replaced by new buds the next day. Bloom slows in cool or cloudy weather and stops with frost.

Detailed Descriptions

Flower Description

Blue, lavender, or white

Foliage Description

Green to silvery grey-green

Growing Conditions

Sun Requirements

SunFull Sun

Requires 6-12 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

Soil Requirements

pH Range6.0 - 7.5(Neutral)

357912

Soil Types

sand loam

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

tender

Time to Maturity

Flowers within 10-12 weeks from seed

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Evolvulus spp. grows in full sun and light, free-draining soil and tolerates heat, drought, and coastal conditions once established. Constant wet soil causes root rot, so plants are watered only as the soil dries. Light feeding supports steady bloom in containers and beds. The genus is frost tender, perennial only in roughly USDA zones 8 to 11, and is treated as a warm-season annual elsewhere. Trimming straggly stems keeps mounds dense, as older plants tend to open up at the center.

Pruning

Stems are trimmed lightly through the growing season to keep plants compact and to renew growth that becomes bare at the base. A harder cutback in spring restarts plants kept over winter. No other pruning is needed.