A very compact perennial with domed clusters of purple flowers on purple red stems. Height and spread 80cm. Flowers from July to September. Full sun/partial shade. Hardy. Attracts bees and butterflies.
Eupatorium purpureum ‘Ruby’ is a compact, eye-catching perennial known for its domed clusters of purple flowers held on striking purple-red stems. Flowering from midsummer to early autumn, it is a favourite among bees and butterflies and adds height, colour, and movement to borders. Follow this complete guide to help your Eupatorium purpureum ‘Ruby’ thrive season after season.
PLANTING and AFTERCARE GUIDE
Best Planting Time
Spring: The best time to plant Eupatorium purpureum ‘Ruby’ is in spring, when the soil is naturally warming. This allows the plant to root strongly and prepare for its summer flowering period.
Autumn: Eupatorium can also be planted in early autumn, giving the roots time to settle before winter dormancy and resulting in robust growth the following year.
Site Selection
Sunlight: Eupatorium grows beautifully in full sun or partial shade. Choose a site with several hours of good light to promote strong stems and abundant blooms.
Soil: Moist, fertile, well-drained soil is essential. Eupatorium particularly appreciates soil that retains moisture without becoming waterlogged. Adding compost enhances both structure and drainage.
Planting Instructions
Prepare the Hole: Dig a planting hole twice the width of the root ball and of equal depth. Eupatorium purpureum ‘Ruby’ benefits from ample space to establish a healthy root system.
Soil Preparation: Incorporate organic matter such as garden compost or leaf mould to enrich the soil. This supports vigorous early growth.
Planting: Place the plant into the hole so that the top of the root ball is level with the soil surface. Backfill gently and firm the soil to eliminate air gaps.
Watering After Planting: Water thoroughly after planting to help settle the soil and encourage strong root development.
Watering Requirements
Growing Season: Eupatorium prefers consistently moist soil. Water during dry spells and allow the soil surface to dry slightly between waterings to avoid oversaturation.
Dormant Season: In winter dormancy, watering needs are minimal. Only water if the soil is becoming overly dry.
Feeding
Spring: Apply a balanced, slow-release fertiliser in early spring to give Eupatorium purpureum ‘Ruby’ the nutrients needed for healthy new growth.
Mid-Summer: A light summer feed can help extend flowering and maintain plant vigour throughout the season.
Pruning
Deadheading: Remove faded flower heads to keep your Eupatorium looking tidy and to encourage continued flowering.
Autumn Pruning: After flowering finishes in autumn, cut back stems to ground level. This prepares the plant for winter dormancy and promotes fresh, healthy regrowth the following year.
Mulching
Spring: Apply a generous layer of mulch around the base of Eupatorium purpureum ‘Ruby’ to retain moisture, improve soil quality, and suppress weeds.
Winter: A winter mulch helps protect the roots and stabilises soil temperature through the colder months.
Supporting the Plant
Staking: Eupatorium usually forms sturdy upright stems, but in exposed garden positions, staking may be helpful to prevent wind damage.
Final Tips
Eupatorium purpureum ‘Ruby’ is a low-maintenance perennial that performs beautifully in mixed borders and wildlife-friendly gardens. By planting it in fertile, moist soil with good sunlight, and by following this care routine, your Eupatorium purpureum ‘Ruby’ will reward you with vibrant purple blooms and a lively display of visiting pollinators from midsummer to early autumn.
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Lesley Boswell (verified owner) –
Karen Little (verified owner) –