Speedwell flowers are herbaceous perennial plants commonly called Veronicas. These plants are typically hardy, easy-to-grow and easy to recognise because of their tall flower spikes. Most speedwell flower varieties prefer well-drained soils in full-sun locations. Select speedwell flowers for your landscape according to the plant's bloom colour, flowering time, your USDA hardiness zone and your intended usage.
"Nana" is a spiked speedwell variety (Veronica spicata) that winters well in USDA zones 3 to 8. Dense spikes of small, dark blue flowers bloom from June through August. The greyish-green leaves have a lance-like shape. Mature plants range from 6 to 9 inches in height, with spreads ranging from 9 to 12 inches. This hardy plant has no potentially serious pest or health problems. "Nana" prefers well-drained soils in fully sunny locations, but can tolerate light shade conditions. Use the "Nana" speedwell variety in your border fronts or rock gardens.
The "Darwin's Blue" plant forms clumps that reach 18 inches in height and 12 inches in width. This speedwell variety (Veronica spicata) features dense spikes of small, purplish-blue flowers and deep green leaves. The flowers bloom throughout the summer, adding a nice contrast to rock gardens or border fronts. "Darwin's Blue" speedwell prefers fertile, consistently moist soils in fully sunny positions. Flowers planted in poorly draining soils sometimes suffer from root rot. This speedwell variety also works well as an edging plant.
"Alba" is a Gentian speedwell variety (Veronica gentianoides) that blooms from May through July, featuring cupped white flowers with blue tints. These flowers rise from clumps of shiny, dark green leaves. Mature plants form mats that range from 12 to 18 inches in both height and spread. This speedwell species performs best in moist, humus-rich soils and cannot tolerate drought conditions. Although this variety prefers fully sunny locations, it tolerates partial shade. "Alba" winters well in USDA hardiness zones 4 to 7 and has few health or pest problems. Use "Alba" speedwell in your perennial border fronts or rock gardens.
"Georgia Blue" bears, small blue flowers that appear in April and May and often re-bloom during the summer months. Leaves emerge reddish-green, mature to dark green and turn bronze shades in the autumn. This speedwell variety (Veronica peduncularis) ranges from 6 to 9 inches in height and 6 to 12 inches in width. Plant "Georgia Blue" in well-drained soils that receive full sunlight. Few pests or diseases bother this plant. Use "Georgia Blue" as a flowering groundcover or as an edging plant.
"Nestor" is a prostrate speedwell variety (Veronica prostrata) that blooms with light blue flowers from May through July. This speedwell variety sometimes re-blooms throughout the summer. The green foliage forms mats ranging from 3 to 6 inches in height and 6 to 18 inches in width. Winter hardy in USDA zones 5 to 8, "Nestor" speedwells prefer well-drained soils in partially shady to fully sunny locations. This plant cannot tolerate overly wet soils. Few diseases or insects seriously affect this plant. Use the "Nestor" speedwell variety as a groundcover or trail the plant over garden walls.