Gladiolus communis subsp. byzantinus

How to grow gladioli

Find out all you need to know about growing gladioli, in this detailed Grow Guide.

A table displaying which months are best to sow, plant and harvest.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Plant
Plant

Do not Plant in January

Do not Plant in February

Do Plant in March

Do Plant in April

Do not Plant in May

Do not Plant in June

Do not Plant in July

Do not Plant in August

Do not Plant in September

Do not Plant in October

Do not Plant in November

Do not Plant in December

Flowers
Flowers

Plant does not flower in January

Plant does not flower in February

Plant does not flower in March

Plant does not flower in April

Plant does flower in May

Plant does flower in June

Plant does flower in July

Plant does flower in August

Plant does not flower in September

Plant does not flower in October

Plant does not flower in November

Plant does not flower in December

Cut back
Cut back

Do not Cut back in January

Do not Cut back in February

Do not Cut back in March

Do not Cut back in April

Do not Cut back in May

Do not Cut back in June

Do not Cut back in July

Do not Cut back in August

Do Cut back in September

Do not Cut back in October

Do not Cut back in November

Do not Cut back in December

Gladioli are often known as sword lillies due to their long, pointed leaves. The distinctive tall flower spikes emerge in summer and come in a whole host of colours. Although they have suffered from an unfashionable reputation, despite being popular props for musicians and performers, they are sneaking back into favour. It’s not hard to figure out why, as they’re perfect for bringing colour to a sunny herbaceous border, providing good contrast with grasses and other flowering plants. They also look good in containers and make excellent cut flowers.

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How to grow gladioli

Grow gladioli in moist but well-drained soil in full sun. Dig up corms to overwinter indoors if you live in the north of the UK, or mulch above them to overwinter them in the soil. Divide congested clumps every few years.

More on growing gladioli:


Where to plant gladioli

Gladioli originate from hot, dry climates, in South Africa or Mediterranean countries. So they require good drainage and plenty of sun. For best results grow in moist, but well-drained soil, in full sun.


How to plant gladioli

Planting gladiolus corms
Planting gladiolus corms

Plant gladiolus corms in spring. If you’re planning to use them for successional colour, plant a handful a week or so apart from March onwards, to extend the display. You can plant gladioli corms directly into borders, adding plenty of organic matter – well-rotted manure is good. Or plant in pots that you can plunge into borders as they come into flower.

Here, Monty Don demonstrates how to plant gladioli corms in a pot, to plant into the garden later:


How to care for gladioli

Water well during the growing season and stake plants before the flower spike emerges. While in flower, give your gladioli tomato feed or comfrey feed every couple of weeks. For tender varieties, and in colder parts of the country, lift the corms each autumn and overwinter them in frost-free conditions. For hardier varieties, cover with a thick mulch in autumn to protect from cold snaps. Divide congested clumps every few years.

Find out how to give gladioli the best possible growing conditions, in our Quick Tips video with Lucy Hall:


How to propagate gladioli

Cutting back gladiolus for storing
Cutting back gladiolus corms for storing

Over time, clumps of gladiolus get congested, resulting in weaker plants with few or no flowers. To prevent this, divide clumps every few years, in autumn, selecting the best new corms for replanting the following spring (see notes on overwintering lifted corms below). Alternatively, if you’ve previously had success with overwintering your gladioli in the ground, you could wait until spring to divide and replant the corms.


Growing gladioli: problem solving

Sap-sucking gladiolus thrip can attack plants, causing white flecks to appear and sometimes flower buds will go brown and drop off. Prevent the spread of thrips by removing affected foliage and flowers. Gladioli can also fall prey to slugs and aphids and grey mould.


Gladioli varieties to try

Gladiolus 'Hastings'
Gladiolus ‘Hastings’
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  • Gladiolus ‘Miss Green’  – with tall spikes of white-green flowers. Hailing from the Mediterranean region, Gladiolus ‘Miss Green’ is frost tender
  • Gladiolus ‘Hastings’ – bears tall spikes of orange/brown flowers. In warmer regions it may survive outdoors all year round, particularly if the corms are given a thick mulch in autumn. However in colder regions it’s best to lift the corms each autumn to overwinter in frost-free conditions.
  • Gladiolus nanus ‘Charm’ – one of the hardier gladioli, this has masses of violet pink flowers enhanced by a pale white blotch at the lower lip of the flower.
  • Gladiolus ‘Happy Weekend’ – produces tall spikes of apricot flowers.
  • Gladiolus colvillei ‘The Bride’ – a fantastic gladiolus, bearing pretty, delicate white blooms from late-spring to mid-summer. Plant bulbs in autumn rather than spring. Not fully hardy.