Agapanthus

How to grow agapanthus

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Plant
Flowers
Cut back

More on growing agapanthus:

Learn more about growing agapanthus in our Grow Guide, below.

Where to grow agapanthus

Agapanthus with grasses — How to grow agapanthus - agapanthus growing with grasses

Full sun and a well-drained soil are the secrets to success with agapanthus. Plants are able to cope in a coastal situation and are not fazed by sea winds and salty air. Agapanthus are drought-tolerant plants and able to cope in a gravel garden that isn’t watered. Agapanthus tend to flower better if their roots are restricted, so do well in pots.

How to plant agapanthus

Agapanthus rootball

Plant agapanthus in spring in pots or directly into the garden, ideally at the foot of a south-facing wall or similar, to offer protection in winter.

When planting in pots, choose a terracotta pot, which will keep the roots warm in summer. Use a soil-based compost such as John Innes No. 2 or 3, and feed plants in spring with a slow release fertiliser.

Watch Monty Don demonstrate how to plant agapanthus in a pot:

How to care for agapanthus

Water agapanthus planted in the garden for the first year after planting. Those grown in pots will require watering more regularly. Pot-grown agapanthus will benefit from an annual feed – a liquid tomato feed is ideal.

Deadhead spent blooms to encourage more to form, or leave the faded flower heads in place if you want to collect the seed. The attractive seedheads are often left on over autumn for decorative reasons. On a warm autumn day and before the first frosts, cover the crowns of the hardy deciduous agapanthus with straw, to protect over winter. Leave the foliage uncut as this provides additional winter protection.

Some tender, evergreen agapanthus may survive winter, but it's best to move them indoors in case of severe winter weather. Lift garden plant and pot them up in a cool, light but frost-free place for winter, and move pot-grown agapanthus under cover, too.

How to propagate agapanthus

Dividing agapanthus clump — How to grow agapanthus - dividing an agapanthus clump

Divide congested clumps of agapanthus every four or five years. Lift the plants and carefully divide the crown with a sharp spade, making sure that each section has at least two growing points. You may need to use two garden forks back to back to divide very established clumps. This can be done in spring or after flowering in autumn.

Agapanthus species can be grown from collected seed but the cultivars will not come true to type.

Growing agapanthus: problem solving

Agapanthus closeup — How to grow agapanthus - agapanthus closeup

Agapanthus a fairly trouble free if grown in the right place. The most commonly asked question is ‘Why aren’t my plants flowering?’. This is often due to plants being grown in pots or nutrient-rich compost that offer too much root room. Reduce the size of the container – plants that are very happy don’t see the need to flower.

If you grew your plants from seed they can take up to four years to flower, and it's not unusual for some plants to take a couple of years to flower after planting.

Agapanthus varieties to try

Agapanthus 'Albus' — How to grow agapanthus - Agapanthus africanus 'Albus'

Agapanthus africanus ‘Headbourne Hybrids’ – offering a very full head of lilac-blue flowers in August to October that are held on stems 1m in height. A deciduous type that will overwinter in a sunny, sheltered spot. A popular plant
Agapanthus africanus ‘Albus’ – stunning white flowers from August to October. Will overwinter outdoors if in a sunny, sheltered spot. Reaches a height of 70cm

Agapanthus inapertus ‘Midnight Cascade’ – dark blue flowers from August to September. Needs a sheltered spot to overwinter outside. Reaches a height of 70cm

Agapanthus ‘Blue Triumphator’ – Clear blue flowers in August and September. Needs a sheltered spot to overwinter outside. Reaches a height of 80cm

Agapanthus ‘Jacaranda’ – an early flowering type offering blue flowers in June through to August. Height of 90cm

Frequently asked questions

Do agapanthus come back every year?

Agapanthus are perennials which means they come back each year. Most are hardy, and their leaves will die back each winter before returning in the spring. Evergreen types tend to be more tender, so will need some protection in the winter and early spring.

Are agapanthus better in pots or in the ground?

You can grow agapanthus either in pots or in the ground. But they flower better if their roots are restricted, so they will do well grown in pots. Grow in terracotta pots so that the roots stay warm in the summer. Growing evergreen varieties in pots allows you to bring them inside for the winter.

Does agapanthus like sun or shade?

Agapanthus will grow best in full sun. Avoid growing in shade, as they won't flower as successfully.

Help! Is my agapanthus dead?

Evergreen agapanthus are less hardy than deciduous types and can be damaged by prolonged periods of frost. This damage results in 'mushy' or rotten leaves, which may attract small flies. As long as the roots haven't been affected, your agapanthis will bounce back in spring. Simply pull away any leaves that come away easily. If frost is still likely, cover with horticultural fleece or move indoors if your agapanthus is growing in a pot.