Gentian speedwell
Veronica gentianoides · Plantaginaceae
Slender spires of the palest ice-blue flowers, veined in darker blue, rise in late spring from a carpet of glossy, evergreen rosettes.
- Size
- 16 in tall, 18 in wide
- Zones
- 4 to 8
- Light
- Full sun to part sun
- Flowers
- Mid May to mid June
- Pets
- Not checked
- Job in a bed
- Carpet
A bed built around gentian speedwell
The planner designed this bed around gentian speedwell when this page was made: a 12 × 6 ft (3.7 × 1.8 m) cottage garden in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why gentian speedwell stands where it does.
The plants
- 1 Gentian speedwell × 10, blue
- 2 Dianthus 'Kahori' × 5, pink
- 3 Leadwort × 13, blue
- 4 Italian bugloss 'Dropmore' × 3, blue
- 5 False sunflower 'Summer Sun' × 3, yellow
- 6 Inkberry 'Gem Box' × 1, dark green leaves
- 7 Meadow saffron × 5, white
- 8 Surprise lily × 10, pink
Why this plant
- The only spires. The others are open bowls, dense clusters, airy sprays and others. Shape reads at a distance, where colours blur.
Why here
- Under the taller plants. It runs back between them as living mulch: there its job is to cover the soil, not to be looked at.
- 10 plants in 2 groups (7 and 3). Seen again further along, the same plant ties the bed together.
Why now
- In flower for five weeks. From mid May to mid June.
- In company. With dianthus 'Kahori' and Italian bugloss 'Dropmore' in late May: 3 kinds at once.
- One of three evergreens. They are what the bed has to show from November to March.
Planned as a cottage garden: 28 of the 35 plants (80%), bulbs aside, stand alone or in groups of no more than five, small enough for the kinds to mingle. The bed is balanced: the left half carries 49% of the visual weight and the right half 51%. Blue runs through the planting: 3 of the 7 kinds grown for their flowers have it.
The planner's own design check: 9 Excellent, 8 Good.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where gentian speedwell goes in a border
At 16 in it belongs at the front of a bed. In the planner's ten height classes it is short (12 to 18 in).
Its job: carpet. A groundcover planted in threes and fives to cover the soil: along the front, and just behind it.
It flowers before other speedwells, with the late tulips. The pale blue is cool and elegant, and the rosettes make a neat groundcover for the rest of the year.
- Pale blue for late spring
- Evergreen groundcover at the front
- Planting with late tulips
What to plant with gentian speedwell
Plants recorded as good partners for it, and what each pairing does:
- Tulip.
- Lady's mantle: in flower together for three weeks, from late May; a low mound at the foot of its spires; happy in the same moist soil.
- Bergenia: flowers first, mid April to early May, so the spot is never empty; bold leaves against its medium ones; a low mound at the foot of its spires.
Questions about gentian speedwell
Does gentian speedwell need sun or shade?
Gentian speedwell grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).
It wants soil that stays evenly moist, of average fertility, and a good soak in dry spells.
What zones does gentian speedwell grow in?
USDA zones 4 to 8. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does gentian speedwell flower in my zone?
In zone 5 it flowers mid May to mid June. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 4 | Late May to late June |
|---|---|
| Zone 5 | Mid May to mid June |
| Zone 6 | Early May to mid June |
| Zone 7 | Early May to early June |
| Zone 8 | Late April to early June |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should gentian speedwell be planted?
14 in (35 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 18 in (45 cm), so a group knits into one patch.
It grows 16 in (40 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many gentian speedwell plants do I need?
At 14 in apart, set out in staggered rows:
- 9 to fill 10 square feet (about 1 m²)
- 9 for a single row 10 ft (3 m) long
- 28 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as threes and fives, along the front and just behind it.
In the bed above, the planner used 10 in two groups.
Is there a native plant like gentian speedwell?
Gentian speedwell is not native to North America. These North American natives come closest to doing its job:
- Robin's plantain 'Lynnhaven Carpet': the same job in a bed and the same flowering time; 10 in shorter, lavender, not blue.
- Wild strawberry: the same job in a bed and the same flowering time; 10 in shorter, white, not blue.
- Lingonberry: the same job in a bed and the same flowering time; 8 in shorter, pink, not blue.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
What flowers after gentian speedwell?
Gentian speedwell is over by mid June. These start as it finishes and carry the same spot on, so it never goes flat:
- Creeping thyme: from early June to mid July, 3 in tall, to stand in front of it and cover its fading stems.
- Black-eyed Susan: from mid July to mid September, 24 in tall.
- Butterfly weed: from late June to early August, 24 in tall.
What does gentian speedwell look like in winter?
Gentian speedwell keeps its dark green leaves all winter, so it is one of the plants that hold a bed together from November to March, when the perennials have gone.
More Veronica
- Long-leaved speedwell Veronica longifolia
- Speedwell 'Georgia Blue' Veronica umbrosa 'Georgia Blue'
- Speedwell 'Red Fox' Veronica spicata 'Rotfuchs'
- Speedwell 'Royal Candles' Veronica spicata 'Royal Candles'
- Speedwell 'Sunny Border Blue' Veronica 'Sunny Border Blue'
- Spike speedwell Veronica spicata
- Woolly speedwell Veronica incana
In these guides
- Groundcover plants
- Evergreen perennials, ferns and grasses
- Plants with spires: vertical accents
- Plants with blue flowers
Every fact on record
- Type
- Perennial (groundcover)
- Size
- 16 in (40 cm) tall, 18 in (45 cm) wide
- Plant
- 14 in (35 cm) apart
- Height class
- Short (12 to 18 in)
- Place in the bed
- Front
- Flowers
- Mid May to mid June; upright spires; blue, white
- Leaves
- Medium texture, evergreen; dark green
- Shape
- Mat-forming, spreading
- Hardy in
- USDA zones 4 to 8
- Light
- Full sun, part sun
- Soil
- Average, evenly moist
- Water
- Moderate
- Feeding
- None needed
- Family
- Plantaginaceae
Not yet checked against an outside reference: its figures rest on general horticultural knowledge. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.