Family : Convolvulaceae
Text © Pietro Puccio
English translation by Mario Beltramini
The species is native to Bolivia, French Guyana, Guyana, Northern and Eastern Brazil, Northern Argentina, Paraguay, Surinam, Uruguay and Venezuela where it grows in open spaces at low altitudes.
The name of the genus comes from the Latin verb “evolvo” = to unwrap, to unroll; with reference to the absence of wrapping branches as in many species of the family; the specific name is the Latin adjective “glomeratus, a, um” = grouped, gathered, with reference to the inflorescences.
Common names: blue daze, Brazilian dwarf morning glory, Hawaiian blue eyes, (English); azulzinha, evólvulo, sete-sangrias (Portuguese-Brazil); daze azul, evólvulo (Spanish).
The Evolvulus glomeratus Nees & C. Mart. (1823) is a perennial prostrate semi-shrubby species, evergreen, 25-40 cm tall, with pubescent branches rooting on the soil that can cover a surface of 0,6-1 m of diameter. Alternate sessile leaves, simple, oblong-lanceolate with entire margin and obtuse to subacute apex, of green colour and covered by a fine light grey tomentum, 1,5-3 cm long and 0,6-1,5 cm broad. Axillary and terminal sessile sub-globose inflorescences, thick, bearing sessile flowers opening gradually with penta-parted calyx of white colour, hairy, with lanceolate lobes having pointed apex, about 0,5 cm long, imbutiform corolla, of 1,2-1,8 cm of diameter, with 5 lobes of lavender to intense blue colour and white centre. The flowers last one day only, open in the morning and close at the sunset or during the cloudy days, but are produced continuously. The fruit is a globose capsule of about 2 mm of diameter containing 1-4 seeds. Several varieties have been selected with bigger flowers, of up to about 2,5 cm of diameter, and various shades of colour.
It reproduces by seed, division and semi-woody cutting in summer, with a high percentage of success.
Species with thick ornamental foliage and abundant and long lasting blooming, ideal as covering or drooping from a wall or from an escarpment and for edges and rocky gardens. Cultivable in the tropical and subtropical regions, marginally in the temperate-warm ones sheltered from the winter rains, in full sun, for an abundant blooming, or at most a light shade. It is not particular about the soil, from slightly acidic to slightly alkaline, provided perfectly draining, being easily subject to root rotteness. Of easy cultivation, once well rooted does not require particular cares, tolerates short periods of drought, but not the water stagnations, therefore the waterings are to be duly spaced in way to maintain the soil moderately humid; the leaves are not to be left wet for long time, particularly in presence of rather low temperatures, in order to avoid rotteness. Furthermore, it has a good resistance to the saltiness, consequently it can be utilized in the gardens located close to the sea. Light prunings may help to maintain the compact habit and stimulate the blooming.
Of fast growth, in the less favourable climates is employed as annual, sowing in late winter in protected ambient and planting in late spring. It is easily cultivated in flower boxes and pots, of great effect in the suspended ones, for the decoration of open spaces or winter gardens and very luminous verandahs, where it can be sheltered in winter where the climate does not allow the permanence in open air, utilizing a fertile loam with addition of sand or perlite per a 30% to improve the drainage. The waterings must be frequent in summer, allowing the substratum to partially dry up before giving water again, spaced in winter, but without ever allowing the substratum to dry up completely. The lowest temperatures must preferably maintain over the 16 °C, even if it can stand some degree less without damages if maintained fairly dry. Fertilizations from spring to early autumn with hydrosoluble products for flowering plants at 1/3 the dosage suggested on the package.
Synonyms: Evolvulus echioides Moric. (1838); Evolvulus glomeratus f. genuinus (Meisn.) Ooststr. (1934); Evolvulus glomeratus subsp. obtusus (Meisn.) Ooststr. (1934).
The photographic file of Giuseppe Mazza