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How to Grow Nierembergia Plants

Guide to Growing Cupflower and Whitecup

Nierembergia plants are a genus of mat growing plants that reach from 5 to 60 cm (2 to 24 inches) in height.

They are usually grown as half hardy annuals in the garden, but are in fact half hardy perennials.

Nierembergia caerulea
Nierembergia caerulea by Windsurfgirl; creative commons.

Nierembergia have small feathery leaves and white or purple flower that have an attractive purple inner. Plants come into bloom in the summer.

Their size and nature make Nierembergia an ideal plant to grow in rock gardens, or as an edging plant.

Some common names for Nierembergia include Cupflower and Whitecup.

Dwarf cupflower
Dwarf cupflower by Beautifulcataya; creative commons.

How to Grow Cupflower and other Nierembergia Plants in the Garden

Cupflowers like to grow in a sunny part of the garden that has good drainage and a rich moist soil.

The cupflower seeds can be sown either at the start of autumn or early in spring. Once sown lightly cover the seeds with soil.

To grow cupflowers indoors, sow the seeds about 10 weeks in advance. Nierembergia plants can be planted out in early spring or early autumn.

They take about two to four weeks to germinate at 21 to 25 degrees centigrade (70 to 77°F).

Once ready, transplant into the garden using a spacing of about 15 to 20 cm (6 to 8 inches).

Caring for Cupflower

Once growing it is important to keep the soil that Cupflower (and other Nierembergia) plants grow in moist.

Nierembergia plants should be deadheaded to produce more flowering, and cut back in the autumn.

In the spring apply a top dressing of manure. If you require more Nierembergia, then cuttings can be took in the autumn, or they can be divided in the springtime.

Nierembergia Plant Growing and Care Guide

Common Names: Cupflower, Whitecup, Purplecup
Family: Solanaceae.
Life Cycle: Half hardy perennial commonly grown as a half hardy annual by gardeners.
Height: 4 to 12 inches (10 to 30 cm).
Native: South America.
Growing Region: Zones 2 to 10. As a perennial in zones 7 to 10.
Flowers: Summer.
Flower Details: White, blue, purple, lavender. Often veined with deeper colours. Yellow or white centres. Cup-shaped. Upright.
Foliage: Oval. Feathery. Smooth.
Sow Outside: Cover seed. Before last frost or in autumn. Spacing 6 to 10 inches (15 to 25 cm).
Sow Inside: Germination time: two to three weeks. Temperature 70°F (21°C). Nine or ten weeks in advance. Transplant outdoors a few weeks before the last frost or in autumn.
Requirements: Full sunlight or light shade. Good drainage. Rich soil. Moist soil. Manure top dressing in spring. Regular watering to keep soil moist. Deadhead. Perennials should be cut back to the ground in autumn. Propagate: dividing in the spring; cuttings in autumn.

Common Questions

How many members does the Nierembergia genus contain?

The Nierembergia genus contains about 30 species. These South American natives are generally grown as annuals or perennials, depending on the climate.

Do Nierembergia members make a good garden or landscaping plant?

Yes, Nierembergia are excellent garden plants. Their small, bell-shaped flowers are charming in containers, hanging baskets, or as ground cover.

Which Nierembergia species are most frequently grown by gardeners?

The species Nierembergia scoparia (Cupflower) and Nierembergia hippomanica (White Cupflower) are most frequently grown for their continuous bloom throughout the summer.

Are Nierembergia plants fragrant?

Nierembergia plants are not typically noted for their fragrance. Their appeal lies in their profusion of charming, cup-shaped flowers.

What is the perfect location to grow Nierembergia?

Nierembergia prefers a sunny to partially shaded location with well-drained soil. They can withstand heat and are fairly drought-tolerant once established.

Is Nierembergia invasive in the USA, if so in which states?

Nierembergia species are not considered invasive in the USA. They are generally well-behaved plants in the garden.

How do I remove Nierembergia plants from my garden?

Being shallow-rooted, Nierembergia plants can be easily removed by pulling or digging up. Regular deadheading can prevent unwanted self-seeding.

Summary

The Nierembergia genus is a member of the Solanaceae family, is a group of perennial and annual plants, often known as cup flowers. They're recognized for their attractive bell or cup-shaped flowers, which bloom over a long period in summer.

Nierembergia plants are ideal for sunny borders, rock gardens, or containers. They prefer full sun and well-drained soil. Planting is typically done in the spring. Once established, they require minimal maintenance, rewarding gardeners with their vibrant, long-lasting blooms.

I hope that you enjoyed this guide on how to grow Nierembergia plants. You may also enjoy the following Gardener's HQ growing guides: How to grow Chinese Lanterns, Erigeron plant, and Schizanthus plants.