Verbena

Verbena
Genus:	Verbena
Family:	Verbenaceae
Type:	Annuals, Perennials
Pollination:	Insects

Verbena (Verbena or Vervain) is a genus of about 250 species of annual and perennial herbaceous plants in the Verbenaceae. The majority of the species are native to the New World from Canada south to southern Chile, but a few also native in the Old World, mainly in Europe (V. officinalis, V. supina).

Description

The leaves are usually opposite, simple, and in many species hairy, often densely so. The flowers are small, white, pink, purple or blue, with five petals, and borne in dense cymes or panicles.

The stems are square in cross section. Roots are fibrous.

Uses

Grown for the showy flowers and generally good foliage, but some species are used as medicinal and culinary herbs.

Maintenance

Propagation

Propagated by seed, division, or summer cuttings.

Harvesting

Pests and diseases

Bacterial Wilts

• Pseudomonas solacearum

Powdery Mildew

• Erisiphe chichoracearum

Leaf Spots

• Septoria

Flower Blights

• Botrytis cinerea

Stem Rots

• Macrophomina phaseoli
• Pellicularia filamentosa
• Phymatotrichum omnivorum
• Thielaviopsis basicola

Rusts

Nematodes

• Aphelenchoides olesistus
• Meliodgyne hapla

Aphids

• Foxglove Aphid: Acyrthosiphon solani
• Melon Aphid: Aphis gossypii
• Green Peach Aphid: Myzus persicae

Whiteflies

• Greenhouse Whitefly: Trialeurodes vaporariorum
• Silverleaf Whitefly: Bemisia argentifolii

Scales

• Cottony Cushion Scale: Icerya purchasi

Bugs

• Tarnished Plant Bug: Lygus lineolaris
• Greenhouse Orthezia: Orthezia insignis

Thrips

• Western Flower Thrips: Frankliniella occidentalis
• Flower Thrips: Frankliniella thricti
• Greenhouse Thrips: Heliothrips haemorrhoidalis

Beetles

• Clematis Blister Beetle: Epicauta cinerea

Maggots

• Vervain Leaf Miner: Agromyza artemesiae

Caterpillars

• Oblique Banded Leafroller: Choristoneura rosaceana
• Yellow Woolybear Caterpillar: Diacrisia virginica
• Vervain Bud Moth: Endothenia hebesana
• Morning Glory Leaf Cutter: Loxostege obliteralis
• Garden Webworm: Loxostege similalis
• Tobacco Budworm: Heliothis virescens

Mites

• Broad Mite: Rhizoglyphus echinopus
• Cyclamen Mite: Steneotarsonemus pallidus
• Two-spotted Spider Mite: Tetranychus urticae

References

• Ann Fowler Rhoads and Timothy A. Block (2000). The Plants of Pennsylvania: An Illustrated Manual. Anna Anisko, illustrator. Morris Arboretum, University of Pennsylvania Press. pp. 698-699. 
• Christopher Brickell and Judith D. Zuk (1997). The American Horticultural Society A-Z Encyclopedia of Garden Plants. DK Publishing. pp. 1044-1045. 
• Staff of the L. H. Bailey Hortorium (1976). Hortus Third: A Concise Dictionary of Plants Cultivated in the United States and Canada. Cornell University Press. pp. 1148-1149. 
• Pirone, Pascal P. (1978). Diseases & Pests of Ornamental Plants (Fifth Edition ed.). John Wiley & Sons, New York. pp. 527-528. 
• Cranshaw, Whitney (2004). Garden Insects of North America: The Ultimate Guide to Backyard Bugs. Princeton University Press. pp. 625. 
• Pippa Greenwood, Andrew Halstead, A.R. Chase, Daniel Gilrein (2000). American Horticultural Society Pests & Diseases: The Complete Guide to Preventing, Identifying, and Treating Plant Problems (First Edition ed.). Dorling Kindersley (DK) Publishing, inc.. pp. 201.