This compact, mounding plant with lots of cup-shaped flowers is a container favorite.
A tender perennial, nierembergia, also known as cupflower, is commonlygrown as an annual.
Nierembergia is native to Argentina.
The plant is valued for its long bloom period from early summer through early fall.
In the landscape, nierembergia looks best in a mass planting.
Plant it in rows along the front of beds or borders or plant it in groups in rock gardens.
Nierembergia also makes an excellent filler plant for containers,hanging baskets, and window boxes.
With its medium height, it visually ties together taller plants and cascading plants.
Harden the plants off before transplanting.
Dig a hole about twice the size of the nursery pot and just as deep.
Place the plant in the center of the hole and backfill with original soil.
Tamp it down and water it immediately.
Continue to water until the plants are established.
Apply mulch around the base of the plant to retain soil moisture.
Young plants initially grow slowly but growth picks up after transplanting.
Space plants 12 inches apart.
Soil and Water
The soil should be rich in organic matter and well-drained.
ApH between 6.6 and 7.5is ideal but nierembergia is quite adaptable to different levels of soil acidity.
Temperature and Humidity
Nierembergia is not winter-hardy below Zone 7 and is commonly grown as an annual.
The bloom period ends with the first fall frost.
Pruning
Removing dieback anddeadheading spent flowershelps to keep the plant looking tidy and extend its bloom period.
Potting and Repotting Nierembergia
Nierembergia makes an excellent container plant.
Use a pot with large drainage holes and fill it with well-draining, rich potting soil.
keep in mind that potted plants need more frequent watering and fertilization than plants in the landscape.
Pests and Problems
The plants are not prone to serious pests or diseases.
You might findslugsand snails feeding on the plants, especially young plants.
Keep the seeds evenly moist.
At a temperature around 70 degrees F., germination takes 2 to 3 weeks.
Place the seedlings in a window with plenty of bright direct sunlight or under grow lights.
Harden seedlings off and transplant them outdoors after the last spring frost.
It grows 8 to 12 inches tall and wide.
‘Mont Blanc’ Nierembergia
Nierembergia scoparia’Mont Blanc' is an All-America Selection winner with pure-white flowers.
It grows 6 inches tall and spreads 12 inches.
‘Purple Robe’ Nierembergia
Nierembergia scoparia’Purple Robe' is a compact variety with violet-blue flowers.
The plant grows 6 inches tall and spreads 12 inches.
This cultivar does especially well in hot and humid summers.
This cultivar grows 10 to 16 inches tall and 18 inches wide.
Most angelonia plants grow upright with spires of flowers and deep green, glossy foliage.
Erect spires of angelonia fit nicely into the middle of a bed or border.
This South American native loves lots of sun and damp soil.
It is hardy in USDA zones 911 and is grown as an annual in cooler climates.
Even without the blooms, they have attractive deep green foliage.
Frequently Asked Questions
It depends on where you live.
In cooler climates, nierembergia is an annual.
It is a popular nierembergia variety with violet-blue flowers that became an All-America Selections winner in 1942.
