In Poland common viper’s bugloss (E. vulgare L.) is the most common species. E. vulgare belongs to medicinal, ornamental and bee plants, since it is a source of nectar and pollen forage. These flowers are frequently visited by bumblebees and honey bees. Flowering specimens of common viper’s bugloss were collected in the area of Lublin. Flowers and their parts were observed using stereoscopic microscopy. The micromorphology of the nectary at the initial stage of nectar secretion was observed in a scanning electron microscope. The rate of nectar production and pollen yield of the plants were determined as well as insects visiting flowers of this species were identified. The nectary, located at the base of the ovary, was found to be fused with its lower part. Nectar is secreted through numerous stomata located in the epidermis of the nectary. Nectar secretion, which starts at the bud stage, lasts throughout the flower life (3–4 days). Over this period, one flower of common viper’s bugloss produces 2.14 mg of nectar with high sugar concentration (48%). Sugar yield of its flowers is on average 9.8 mg/10 flowers. The flowers start to shed pollen at bud break and release the largest amount of pollen during late morning hours. The weight of pollen produced by 10 flowers is 5.4 mg. The present study shows that the flowers of E. vulgare are a very good source of nectar and pollen forage.

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