<em>Echinops</em>: to plant, to grow and to care for

Botany

Echinops are spiny plants, mostly perennials (there are also annuals and biennials), and very hardy. They bear spherical inflorescences at the top of erect stems. They originate from Europe, central and eastern Asia, and tropical Africa. Nearly 190 species are recorded. The most commonly cultivated are Echinops ritro, sphaerocephalus and bannaticus. In the wild, echinops are mainly found in relatively dry habitats, notably on dry short grass meadows, rocky slopes, fallow land and uncultivated ground. This explains why Echinops is undemanding about soil type, grows well in poor soils and tolerates drought. In France, three species occur naturally: Echinops ritro, Echinops sphaerocephalus and Echinops exaltatus.

Echinops belong to family Asteraceae (plants formerly called “Compositae”, comprising nearly 33,000 species). This is the family of daisies, dandelions and oxeyes… but also of thistles and knapweeds, to which echinops are fairly close. Echinops are sometimes called “Globe thistle”. All these plants have inflorescences in heads, gathering a large number of tiny flowers. Unlike dandelions and daisies, which have flat heads (all flowers on the same horizontal plane), Echinops bear spherical heads.

Echinops resemble eryngiums, Eryngium, in their blue–grey colours, silvery stems, graphic inflorescences and spiny aspect.

Echinops sphaerocephalus: Botanical illustration

Etymologically, name Echinops means in Greek “resembling a hedgehog” (Echinos: hedgehog, and opsis: resembling), alluding to the spherical inflorescences. Echinops is also the name of a small mammal, a genus of hedgehog. Common names for the plant include azurite, blue thistle, globe thistle, blue urchin, azure globe…

Echinops grow quickly, forming clumps of erect, ramified stems topped by spherical inflorescences. They can reach between 60 cm and 1.50 m in height, but are often around one metre tall. Echinops giganteus is an exception: it can reach up to five metres! Among commonly grown species, Echinops sphaerocephalus tends to be slightly taller than others.

Echinops have a very open, airy habit, allowing sight through the plants. They create beautiful scenes with light, when spherical inflorescences catch the sun’s rays, or with frost in winter. Stems are sturdy and persistent; if not cut back they remain in place over winter.

Echinops flower in midsummer, from July through August or September. Flowering can sometimes be extended by pruning, removing spent flowers… which encourages the plant to rebloom.

At stem tips they bear blue spheres, earning Echinops the common name “Azure globe”. These distinctive inflorescences resemble small sea urchins and also recall the flowering of Alliums. All flowers are attached at the centre, on a receptacle, and radiate outwards. As the flowers are narrow and elongated they give the impression of a sphere bristling with small points. These inflorescences are highly graphic, forming very round spheres. They usually measure between 3 and 5 cm in diameter… but those of Echinops giganteus are much larger, between 10 and 20 cm in diameter — a true giant Echinops.

These inflorescences are therefore spherical heads, gathering numerous flowers attached to the same axis. Flowers are in fact tiny, but each head contains a very large number! Flowers are tubular. Each is formed of five fused petals (five lobes), and five sepals. Inside the tube formed by the petals are five stamens (male sexual organs carrying pollen), blue-grey in colour, and a style. Flowers are hermaphrodite. They are also surrounded by spiny bracts.

Inflorescences are generally blue–grey; a slightly mysterious hue, both deep and at the same time light, silvery, metallic. Unlike many other flowers, it is not a bright, pure colour. Variety Echinops ‘Arctic Glow’ stands out with white flowers. Spaces between flowers are always somewhat darker, in shadow, adding contrast to the flowering and highlighting each little “point”.

Flowering stems of Echinops are ideal for bouquets. They are very decorative in a vase, both during flowering and afterwards. You can cut the flowers and dry them by hanging heads upside down.

Echinops is a melliferous plant: its flowers are much appreciated by insects. They attract bees and butterflies, which pollinate flowers in exchange for nectar.

Flowering of Echinops sphaerocephalus (photo Drew Avery) and detail of an inflorescence of Echinops ritro (photo Patrick Ch. Apfeld)

Echinops leaves are spiny, elongated and nicely dissected. They are dentate, irregular, thick and leathery. Echinops graecus is distinguished by extremely fine foliage. Leaves bear small spines along the lamina margin, protecting the plant from herbivores tempted to eat it. The prickliest by far seems to be Echinops spinosissimus; its lamina is very reduced but extremely spiny! Echinops leaves measure between 10 and 30 cm long. They are alternate, placed one after another along stems. Basal leaves are larger than those higher up. Lamina is attached directly to stem, without petiole. It is even embracing, more or less surrounding the stem.

Foliage is deciduous, disappearing in winter with the cold.

Usually leaves are dark green (sometimes more or less grey) above, and silvery beneath. Most often the upper surface is glabrous (without hairs), and the underside tomentose.

A leaf of Echinops bannaticus, foliage of Echinops sphaerocephalus (photo Lucy Downey) and underside of a leaf of Echinops exaltatus (photo Rolf Engstrand)

Stems bearing leaves and flowers have a lovely silvery colour. In Echinops ‘Star Frost’, inflorescences share the same tone, making the plant relatively uniform.

Echinops tends to self-seed… It can become somewhat invasive. But it is easy to avoid volunteers by cutting stems after flowering.

Seeds are small elongated achenes, topped by an egret of silk, allowing them to be carried by wind. As in many Asteraceae, Echinops fruits are dispersed by wind. This enables the plant to reach new territories. Seedheads are reminiscent of those of dandelions. They are very decorative, making Echinops interesting in the garden even in winter. They are also appreciated by birds.

Main varieties of Echinops

Most popular varieties

Echinops ritro

One of the most commonly grown Echinops! Its inflorescences have a metallic blue tint before the small flowers open, then become a truer blue. Leaves are green on upper surface, but white and downy underneath. Found growing wild in southern France.

• Flowering time August to October
• Height at maturity 80 cm

See the product sheet

Echinops bannaticus Blue Globe

This Echinops produces spherical inflorescences in summer, a fairly pronounced blue, darker than other varieties. It can reflower (in early autumn) if pruned after flowering.

• Flowering time August, September
• Height at maturity 1,50 m

See the product sheet

Echinops ritro Veitch’s Blue

This variety bears grey-green foliage and flowers in spherical heads, with a fairly dark metallic blue hue. It can also reflower in autumn after being pruned.

• Flowering time August to October
• Height at maturity 80 cm

See the product sheet

Our favourite varieties

Echinops bannaticus Star Frost

This Echinops is notable for its silvery-white inflorescences that harmonise with the supporting stems, making the plant appear entirely silvery.

• Flowering time August to October
• Height at maturity 1 m

See the product sheet

Echinops sphaerocephalum Arctic Glow

A fairly tall Echinops, producing silvery-white spheres in summer, slightly tinged with green. Stems take on a rather dark reddish tint, creating a striking contrast with the paler flowering.

• Flowering time August, September
• Height at maturity 1,20 m

See the product sheet

Planting Echinops

Where to plant?

Echinops are plants that enjoy heat and need good light: plant them preferably in full sun, or possibly in partial shade.

Echinops are easy to grow, undemanding about soil type. They tolerate calcareous soil well. What matters most is that soil is well draining, as they dislike standing water. If your soil tends to retain water, improve drainage (add gravel, coarse sand, etc.).

Echinops do very well in poor, low-fertility and relatively dry soils. It is not necessary to give them compost or fertiliser. On the contrary, avoid planting them in very fertile soils, as they would then produce large, tall stems that are more fragile and would need staking. Plant will look better in poor soil. Echinops also appreciate deep, loose substrates, allowing their roots to penetrate well.

As Echinops like stony, free-draining soils, you can certainly plant them in a rockery, with plants that tolerate drought and enjoy full sun. They are also perfect in borders, alongside other perennials… or at the back of a bed, for the larger varieties!

If location suits it, Echinops tends to self-seed generously! It can even naturalise.

When to plant?

You can plant them in spring (April–May) or in autumn (September–October). Avoid periods of frost or extreme heat.

How to plant?

We recommend planting Echinops in groups rather than singly; or else scatter several plants within same bed, alongside perennials that flower in summer. Maintain about 50 cm spacing, although this also depends on chosen variety.

1. Dig a planting hole. It is not necessary to add compost, but you can improve drainage by adding gravel or coarse sand, or by planting on a mound.
2. Remove your Echinops from its pot and plant it.
3. Replace soil around it, and press down gently.
4. Water generously.

Continue watering until plant is well established.

Echinops ritro (photo Acabashi)

Care

Echinops do not need much maintenance. Except during drought, they do not really need watering. In any case, avoid excess moisture.

Feel free to cut flower stems to make bouquets! They last a long time in a vase. You can dry them by hanging them upside down, flowers pointing downwards. Ideally, place them in a dark, warm, dry and well‑ventilated room.

You can either leave stems in place over winter, as they remain decorative even after flowering, or cut the plant back in autumn. This will prevent self‑seeding, because when it settles in a spot, it can become somewhat invasive.

Cutting flowers when faded can allow the plant to flower again! Some Echinops varieties are perpetual and can produce a second flowering in autumn.

If exposed to wind, Echinops may need staking to help keep stems upright, especially in taller varieties.

As Echinops favours poor soils, there is no need to apply fertiliser or compost. You can optionally lay a layer of mulch around it, as this will limit weed growth and prevent soil from drying out too quickly.

We suggest renewing your plants every three to four years, because over time they become less vigorous.

Echinops is rarely affected by diseases or pests. It can occasionally be attacked by aphids. It also dislikes excess moisture, which can cause it to rot.

Propagation: sowing, division, propagation by cuttings

Echinops can be propagated by sowing, division of clumps or propagation by cuttings of roots. You can also lift volunteer seedlings and transplant them. Multiplying Echinops will allow renewal of plants that might become exhausted over the years.

Sowing

You can sow Echinops in spring, around April, from seeds you have collected or purchased. Sowing can be done in open ground (after last frosts), or in pots.

If you wish to sow directly in place :

1. Choose a sunny spot on well-drained soil. If necessary, add some coarse sand to improve water infiltration.
2. Prepare sowing bed by breaking up clods, remove large stones and weed roots. Level ground to obtain an even, regular surface.
3. Scatter seeds on surface and cover very slightly.
4. Water with a fine spray.

Continue watering in following weeks.

You can also start them in pots. In that case, prepare pots with a good compost for sowing, then place seeds and cover with a very thin layer of substrate: they need a little light to germinate. Water with a fine spray. You can plant in open ground once risk of frost has passed.

Division of clumps

Dividing clumps is a good technique to rejuvenate plants. Carry out in early spring or autumn. We recommend doing this every three to four years.

1. Choose a fairly large clump, several years old
2. Lift it carefully, digging wide enough not to damage roots
3. Divide into several sections
4. Replant each in a new position after preparing soil.
5. Water.

Propagation by root cuttings

You can also propagate Echinops by root cuttings in winter or spring.

1. Prepare a pot with compost mixed with sand.
2. Choose a well-developed clump and lift it carefully, without damaging roots.
3. If necessary, remove excess soil to make roots clearly visible.
4. Choose a lateral root, fairly thick, healthy and well formed
5. Cut it close to base of plant to obtain a fragment 5–10 cm long. Use a sharp, disinfected knife and make a clean cut.
6. Replant original clump in ground and water.
7. Then place root cutting in pot, under a few centimetres of substrate, positioning it horizontally.
8. Cover with compost
9. Water.
10. Place pot under cover, frost-free, in a bright spot.

Water regularly so substrate remains moist (without excess moisture) until plant has established. It should take two or three months to develop.

→ Learn more about propagation by cuttings of Echinops in our tutorial: propagation by cuttings of Echinops.

Companion planting in the garden

To accompany echinops, choose preferably other plants that also enjoy sun and well-drained soil.

You can place echinops in a rockery, with rock geraniums, sedums, lavender, achilleas, Eryngium, santolina… For example, create a raised border with a few large stones and plant between them species that tolerate drought. You can also lay a mineral mulch around plants (gravel, pumice…). You will obtain a garden that requires very little maintenance.

Also consider pairing echinops with other plants in grey or silvery tones. Take advantage of the very soft, wooly foliage of Stachys byzantina… and the silvery leaves of santolinas, Helichrysum italicum, Senecio cineraria, Cerastium tomentosum, Convolvulus cneorum, artemisias (Artemisia schmidtiana or ‘Powis Castle’), or the centaury Centaurea pulcherrima… Enjoy also the impressive foliage of Cynara cardunculus (cardoon, ornamental artichoke)! To add small touches of colour, rely on rose campion, Lychnis coronaria.

By contrast, you can warm up the cool tones of echinops with warm colours. Daylilies, rudbeckias and echinaceas, achilleas with yellow or red flowers (‘Terracotta’ or ‘Paprika’), etc., will warm the border and create a superb contrast. Echinops are perfect alongside larger, vivid-coloured flowers. You can thus compose a superb summer border or a very colourful mixed border! Echinops bring a contrast of form and an airy lightness that highlights brighter flowers and broader foliage.

Because of their light, airy, wild aspect, echinops fit very well into naturalistic gardens. Plant them alongside splendid verbena hastata (Verbena hastata), burnets, agastaches, knautias… Especially since echinops are good melliferous plants. Use them to create a garden favourable to biodiversity. You can also include nigella damascena with its superb, very delicate blue flowers.

You can place echinops in a very natural, wild-style garden. Echinops ‘Arctic Glow’ with Anemone ‘September Charm’ and Pennisetum villosum / Nigella damascena (photo H. Zell) / Verbena hastata (photo Cody Hough) / Knautia macedonica ‘Melton Pastels’

With their very structured aspect and original, metallic colour, echinops allow creation of a modern, graphic garden! Dare contrasts, unusual shades, black, purple, white, silver… Choose other highly graphic plants such as Eryngiums, ferns, bamboos, horsetails, Japanese maples, ophiopogon and grasses.

Echinops can also be incorporated into a romantic garden, with roses, astrances, thalictrums, clematis, agastaches, perovskias… Not forgetting the delicate flowering of Japanese anemones.

You can also choose other very airy-looking plants to accompany them: gaura, perovskia, knautia, nigella… Echinops are perfect combined with grasses: pennisetum, miscanthus, calamagrostis, and above all, Stipa pennata! Also discover the small ovoid spikes of Lagurus ovatus! You will obtain a very light border, both natural and modern in style.

→ Discover other beautiful ideas for pairing with Echinops in our care sheet!

An idea for pairing Echinops sphaerocephalus, Astrantia major, Aconitum ‘Stainless Steel’ and lavender (photo Nicole and Patrick Mioulane – MAP)