- Name also: Common Forget-me-not
- Family: Borage Family – Boraginaceae
- Growing form: Annual or usually biennial, sometimes perennial herb. Taproot short, many-branched.
- Height: 10–40 cm (4–16 in.). Stem ascending–erect, usually branched, round–slightly angular, hair usually growing upwards flush with stem.
- Flower: Regular (actinomorphic), 3–4 mm wide. Corolla blue, fused, funnel-shaped, 5-lobed, protuberances in throat of tube. Calyx fused, campanulate (bell-shaped), 5-lobed, lobes narrow; hairs at base spreading and hook-tipped, flush with calyx at tip, matted; calyx 3–5 mm (0.12–0.2 in.) long in fruiting stage, usually closed, falling with fruit. Stamens 5, filaments fused with calyx-tube. Gynoecium fused, single-styled. Inflorescence a scorpioid cyme, extending to become racemose; all flowers without subtending bracts. Flower-stalk hair almost flush with surface, after flowering approx. 2 times as long as calyx.
- Leaves: Basal leaves stalked, stalk widely winged. Basal leaves usually withered by flowering time. Stem leaves alternate, stalkless. Leaf blade lanceolate–oblanceolate, with entire margin, both sides hairy.
- Fruit: 4-parted schizocarp. Mericarps egg-shaped, glossy, narrowly winged, initially yellowish brown, when ripe almost black, 1.5–2 mm (0.06–0.08 in.) long.
- Habitat: Fields, waste ground, gardens, yards, meadows, rocky outcrops.
- Flowering time: (May–)June–September.
Field forget-me-not is usually an annual or biennial herb. Its success is based on its flexibility. The seeds can wait in the soil for a suitable time to sprout for up to 30 years and germinate when conditions become favourable. Field forget-me-not’s flowers are pollinated by small flies and hymenopterans, and if needs be the plant can also self-pollinate to ensure its seed production. The plant often spreads via the whole calyx, which has hooked hairs that can catch on to animal fur or people’s clothes and carry it to new habitats. Field forget-me-not is happy on different kinds of soil and can be spotted as often on rocky outcrops as in vegetable gardens, where it can be a nuisance weed for farmers and gardeners alike.
It is not always easy to classify the forget-me-nots in their correct species. Important identification markers are e.g. the relative dimensions of the flower, the form of the calyx and its hairiness. Field forget-me-not can be most easily differentiated from early forget-me-not (M. ramosissima) and strict forget-me-not (M. stricta) by its fruit-stalk, which is up to twice the length of the calyx, and also its larger size. When it is not flowering, field forget-me-not can also be confused with field mouse-ear (Cerastium arvense), whose leaves are however opposite one another.