Ornamental Flower
Kew Blue Salpiglossis is a stunning heirloom annual that produces intensely deep blue, almost black blooms with delicate flecks of pollen that shimmer like stars across each petal. This rare painted tongue grows 24 to 30 inches tall and thrives in full sun across hardiness zones 10 to 11, earning its place as a dramatic focal point in summer gardens. The flowers are so arresting that they demand attention, especially when paired with white blooms like moonflower, creating a striking nighttime garden display. Hardy annuals when started indoors 8 to 10 weeks before your last frost date, they prefer moderate watering and well-draining soil with a pH between 6.0 and 7.0.
Full Sun
Moderate
10-11
30in H x ?in W
Annual
High
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The flowers of Kew Blue Salpiglossis are genuinely unlike anything else you'll grow. Deep blue petals so dark they're almost black, dusted with golden pollen that catches the light like constellations, make this a conversation-starting plant. At 2 to 2.5 feet tall, it works equally well as a mixed border plant or in containers, and it blooms reliably all summer once established. The rarity and drama of this painted tongue variety means you're growing something that will stop gardeners in their tracks.
Kew Blue Salpiglossis shines as a focal plant in mixed flower borders and container gardens. Its deep blue, almost black petals make it especially striking when combined with contrasting white flowers like moonflower, creating a high-drama evening display. The height and presence of this cultivar suits it well for back-of-border positioning or as a standout specimen in mixed plantings where its rare coloring can take center stage throughout the summer bloom season.
Start seeds indoors 8 to 10 weeks before your average last frost date. Press seeds into the soil surface without covering, as light aids germination. Maintain a temperature of 70 to 80 degrees Fahrenheit and expect sprouts within 14 to 30 days. Transplant is recommended for this variety.
Transplant outdoors after your average last frost date, since this cultivar is frost-tender. Space plants 8 inches apart in full sun. Harden off seedlings gradually before moving them to the garden.
You may sow outdoors 1 to 2 weeks before your average last frost date in most climates. In mild climates, sow in late summer or fall for cool-season blooms.
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