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How to Grow Hesperis Plants in your Garden

Gardener's HQ Guide to Growing Dame's Rocket, Garden Rocket, Summer Lilac, & Sweet Rocket

Members of the Hesperis genus are woody hardy perennials that grow in height from 30 cm to 1.2 m 91 to 4 feet).

They carry lilac, white or purple flower that carry a fragrant aroma in the nighttime.

They come into bloom in the summer.

Some of the common names for Hesperis include Garden Rocket, Sweet Rocket, Dame's Rocket, and Dames Violet.

Hesperis matronalis
Hesperis matronalis - Dame's Rocket by kirybabe.

Dame's violet
Dame's-violet by anemoneprojectors.

Hesperis Plant Growing and Care Guide

Common Names: Dame’s Rocket, Dames Violet, Garden Rocket, Summer Lilac, Sweet Rocket.
Life Cycle: Short lived hardy perennial usually grown as a hardy biennial.
Height: 12 to 48 inches (30 to 120 cm).
Native: Europe. Asia.
Growing Region: Zones 3 to 9.

Flowers: Summer.
Flower Details: Purple, lilac, white, pink. Fragrant. Four petals. Terminal raceme.
Foliage: Alternate. Lanceolate. Rough.

Sow Outside: Surface. Middle of summer. Spacing 12 to 20 inches (30 to 50 cm).
Sow Inside: Germination time: three weeks to one month. Temperature: 70 to 85°F (21 to 29°C). Two months in advance. Transplant outdoors following the last frost.

Requirements and care: Full sunlight or partial shade, can be grown in shady areas in warm parts. Good drainage. Soil pH 5.0 to 8.0. Provide new seed beds with straw mulch during the winter.
Most soils even poor ones. Regular feed. Prune stems once flowering has completed to encourage further blooming. Propagate: Self seeds readily; or from cuttings.

Miscellaneous: Invasive and banned in some parts of the USA. Often confused with phlox (five petals) but flowers have one less petal. The plant attracts butterflies such as the small white and orange tip, and various species of moths.

How to Grow Garden Rocket and other Hesperis Plants in the Garden

If you are planning to grow Hesperis from seed, then they should be sown on the surface in the middle of summer.

They can grow in sunny, partially shaded and even shaded area (hot locations) of the garden. Plants enjoy a soil that has good drainage, is moist, and has a pH of between 5 and 8.

If you plan to first start growing Garden rocket plant and other Hesperis plants as seedlings indoors, then they should be started about two and a half months before due to be transplanted out. Put out after the last frost of spring.

It usually takes about three to four weeks to germinate at a temperature of 21 to 29 degrees Centigrade (68 to 84°F).

Once growing, they should be spaced at about 30 to 40 cm (12 to 16 inches) apart in the middle of spring.

Caring for Garden Rocket

If you require more plants, then cuttings of Garden Rocket can be readily taken. Although the Hesperis plant is a hardy perennial, it is short-lived, so you may want to sow new plants regularly.

Members of the Hesperis plant genus are easy to maintain. They require regular feeding and cutting back of the stems following flowering, this will produce more blooms.

Common Questions

How many members does the Hesperis genus have?

The Hesperis genus contains about 50 species, often valued for their pretty clusters of flowers.

Do members of Hesperis make a good garden or landscaping plant?

Yes, Hesperis matronalis or Dame's Rocket, with its clusters of fragrant flowers, can add great beauty to gardens, but be aware, it can be invasive.

Which Hesperis species are most frequently grown by gardeners?

The Hesperis matronalis or Dame's Rocket is often grown for its colorful and fragrant flowers that bloom in late spring.

Are members of the Hesperis plant genus fragrant?

Yes, especially the Dame's Rocket (Hesperis matronalis) which has a sweet clove-like fragrance.

What is the perfect location to grow Hesperis?

Hesperis plants prefer full sun to part shade and fertile, well-drained soil.

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

Dame's Rocket (Hesperis matronalis) is currently considered invasive in many states, particularly in the Midwest and Northeast.

How do I remove Hesperis plants from my garden?

To remove Hesperis, dig up the plants ensuring you remove all the roots and seeds to prevent re-growth.

Summary

The Hesperis plant genus belongs to the Brassicaceae family. Native to Europe and Asia, these biennial or perennial plants are known for their four-petaled, fragrant flowers. The most commonly cultivated species is Hesperis matronalis.

Plant out Hesperis in a location with full sun to partial shade and well-drained soil. They require regular watering and perform well in cooler climates. Propagation is usually achieved through seeds, sown in the spring or fall.

I hope that you enjoyed this guide on how to grow Hesperis plants. You may also enjoy my gardening guides on how to grow Bulbocodium, Narcissus plant, and Crinum plants.