How to grow Echium
There are Echium to suit different garden styles, including exotic plantings, borders, dry gardens, containers, meadows, and conservatories. Some need frost-free conditions in winter but, given a sunny spot and free-draining soil, anyone can take on the challenge and enjoy spectacular results.
- Flower spikes range from 50cm (20in) up to 4m (13ft)
- Flowers in shades of blue, purple, pink, red and white
- Most Echium flower during summer
- Suitable for borders or containers
- Thrives in full sun
- Some species require winter protection as they can’t survive frosts
- Echium can be grown from seed and cuttings taken from shrubby plants
All you need to know
Choosing an EchiumEchium vary a lot in size and habit. There are biennials (completing their life cycle in two years), herbaceous perennials (that die down in winter), and shrubs (with year-round structure and foliage). If you choose to grow a frost tender species, consider how and where you can overwinter it, and the practicalities of moving a container large enough for your chosen Echium. More information on the minimum temperatures that different types need can be found in the Echium by hardiness page.
Different species lend themselves well to different styles of planting. When selecting an Echium for your garden bear in mind the following:
- The flower colours of Echium vary, with shades of blue, purple, pink, red and white
- Echium differ greatly in size. E. pininana and E. ‘Pink Fountain’ can exceed 4m (13ft) in height, whereas E. vulgare reaches about 50cm (20in). Many of the shrubby species reach about 1.5m (5ft)
- Their hardiness varies considerably depending upon which species you choose to grow. E. vulgare are reliably hardy throughout the UK. Others like E. wildpretii can be grown outside in mild areas with free-draining soil
- The longevity of Echium plants depends on the species you grow. Cultivars of E. vulgare, for example E. ‘Blue Bedder’ and E. ‘Pink Bedder’, are often used as summer bedding plants
- Echium are toxic if eaten and the leaves and stems may cause skin irritation, so consider wearing gloves when handling
- Choose an Echium that has received the RHS Award of Garden Merit, as these have been assessed and are known to perform well.
Buying an Echium
Echium seeds can be bought from many online seed companies (eg. Plant World Seeds) or garden centres. Growing from seed is a good option, particularly for biennial and short lived plants.
Echium aren’t generally part of the mainstay stock of garden centres, but various nurseries throughout the country stock them. Use our find a plant tool to track down a particular Echium.
A Plant Heritage National Collection of Echium is held at Echium World in Nottinghamshire, from where plants can be ordered online.
Planting an EchiumWhichever Echium you decide to grow, it will do best planted in well-drained soil in full sun.
When to plant
- Planting out container-grown Echium is best done in May when the worst of the winter wet and cold has passed
- If you buy a container-grown plant during the summer, plant it as soon as possible and water it thoroughly
- Self-seeded Echium can be left to continue growing where they have germinated, but may need some winter protection
- Echium are often bought as seeds. See the propagation section below for more details on growing from seed
Where to plant
- Echium grow well in full sun on free-draining soil. If your soil is prone to waterlogging, or you live in a cold area, grow Echium in containers so they can be moved to a sheltered position
- Once established, Echium are fairly drought tolerant
- Many species of Echium will perform much better if grown in a sheltered location, away from frost pockets and strong winds
- E. vulgare is a British native that makes an attractive addition to meadow planting
How to plantIf you have container grown Echium to plant out, plant them the same soil depth that they are in the container.
Echium like well-drained soil and will not thrive where the soil is heavy or overly wet. To improve drainage, dig in plenty of well-rotted organic matter, like leaf mould or manure, before planting.
WateringWatering Echium planted in the ground:
Water after planting to help your plants establish (get their roots down into the soil). Once established they are fairly drought tolerant and should not require frequent watering. However, on very free-draining soil or during prolonged hot dry spells, they may need additional water to support healthy growth. Aim to keep the soil slightly moist, but not soggy.
Echium do not like to sit in wet soil, so there can be a risk of overwatering. Too much water could be a problem in colder months when the plant is not actively growing. A shelter to keep the soil around the Echium dry might be necessary in wet winters.
Watering Echium in pots:
Echium grown in pots will be dependent upon you to provide the water they need. If your pots are kept under cover during winter keep the compost on the dry side, water sparingly.
Ensure that there are sufficient drainage holes at the base of the pot so excess water can drain away. Raising the pot off the ground with pot feet/blocks will also aid drainage.
During the summer when the plant is actively growing, water thoroughly until you see water running out the bottom of the pot. Allow the top of the compost to begin to dry out (it will turn a lighter colour) before the next watering is required.
FeedingEchium need little or no regular feeding on most average garden soils. On poorer soils an application of a general purpose fertiliser in spring, such as Growmore (70g per sq m or 2oz per sq yd) will help promote healthy growth.
If you are growing an Echium in a pot, liquid feeding according to the instructions on the pack will be beneficial in the growing season (April-September).
DeadheadingIt is not necessary to regularly deadhead Echium. Deadheading will encourage more flowers on the small-flowered types, but seeds should be allowed to ripen on the plant if you want to encourage self-seeding, or if you want to collect seeds for sowing.
OverwinteringIf you grow Echium in containers, tender species can be moved to a light, frost-free place to protect them from the cold and wet during winter. A heated greenhouse kept above 5°C (41°F) is ideal. The exact timing for moving plants inside and back outside will vary from year-to-year depending when the first and last frosts occur in your garden. In general, May would be a suitable month to move them outside, and October a suitable month for placing them inside.
Different species have different levels of hardiness (how well they cope with cold temperatures), and it is worth noting that winter wet as well as temperature determines how well a plant survives in the ground outdoors. More information on the minimum temperatures that particular types tolerate can be found in the Echium by hardiness section.
Species that are not reliably hardy throughout the UK (except in the south west and cities) can be wrapped with fleece and kept dry with a temporary waterproof roof. Biennial types like E. pininana grow a rosette of leaves in their first year, this rosette may need protection to ensure it survives the winter to produce flowers the following summer. Echium foliage and crowns are prone to rotting, therefore wrapping shouldn’t be too tight, and the plant should be able to breath.
Caring for older plantSome of the very tall species may require staking if grown in an open, exposed position.
Echium do not require pruning. If you are growing shrubby types (eg. E. candicans) removing old flower spikes and giving it a light trim in October (assuming they are in a frost-free environment over winter) will help to maintain a neat shape and prevent the plant becoming straggly.
Some types of Echium are monocarpic (the plant dies after flowering), these tend to be biennial (completing their life cycle in two years). Although individual plants may not last for many years, they produce lots of seeds that can be collected and sown in spring to make replacements each year.
Propagation of EchiumFrom seed:
Echium can be propagated from seed. The best time to sow seed is from late spring to early summer. Sow into a soil based compost, such as Sylvagrow with added John Innes. After sowing, cover the seed lightly and water sparingly to keep the compost slightly damp to the touch. Echium generally germinate well at temperatures of 13-16°C (55-61°F) and benefit from slight fluctuations between day and night temperatures, as this is what they would experience in their natural habitats.
Seedlings need to be overwintered at 5-7°C (41-45°F), therefore require a frost-free greenhouse, conservatory, or sunny windowsill. Hardy species (eg. E. vulgare) can be direct sown outside, either broadcast or in drills.
Propagating from seed is an inexpensive method of increasing your Echium plants, and cost free if you collect seed from existing plants. Some species will self-seed and you will find young plants at the base of the parent plant that can be transplanted elsewhere. Usually only seed collected from Echium species are the same as the parent plant. Seedlings from a named cultivated variety are likely to be extremely variable in appearance.
Most Echium will take two or three years from seed to flowering. Sow seed and pot on plants each year for a display of flowers every summer.
Cuttings can be taken from shrubby species, either as softwood cuttings in late spring/early summer (May/June), or as semi-ripe cuttings towards the end of summer (August/September).
Echium are generally disease free.
It is important to choose a type of Echium that suits the growing conditions that exist in your garden, or that you can provide, this will result in an impressive display of flowers.
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