How to grow nasturtiums

How to grow nasturtiums

All you need to know about growing nasturtiums in our expert 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
Sow
Sow

Do not Sow in January

Do not Sow in February

Do not Sow in March

Do Sow in April

Do Sow in May

Do Sow in June

Do Sow in July

Do not Sow in August

Do not Sow in September

Do not Sow in October

Do not Sow in November

Do not Sow in December

Plant
Plant

Do not Plant in January

Do not Plant in February

Do not Plant in March

Do not Plant in April

Do Plant in May

Do Plant in June

Do Plant in July

Do 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 not flower in May

Plant does flower in June

Plant does flower in July

Plant does flower in August

Plant does flower in September

Plant does flower in October

Plant does not flower in November

Plant does not flower in December

Collect seeds
Collect seeds

Do not Collect seeds in January

Do not Collect seeds in February

Do not Collect seeds in March

Do not Collect seeds in April

Do not Collect seeds in May

Do not Collect seeds in June

Do not Collect seeds in July

Do not Collect seeds in August

Do Collect seeds in September

Do Collect seeds in October

Do Collect seeds in November

Do not Collect seeds in December

At its best
At its best

Plant is not at its best in January

Plant is not at its best in February

Plant is not at its best in March

Plant is not at its best in April

Plant is not at its best in May

Plant is at its best in June

Plant is at its best in July

Plant is at its best in August

Plant is not at its best in September

Plant is not at its best in October

Plant is not at its best in November

Plant is not at its best in December

  • Plant size

    30cm height

    45cm spread

  • Spacing

    30cm apart

Nasturtium (Tropaeolum majus) is one of the quickest and easiest hardy annual flowers to grow, producing masses of vividly coloured blooms through summer and autumn. They’re perfect for growing with children. Nasturtiums come in both bushy and climbing varieties, which makes them splendidly versatile. Some varieties have attractively marbled or mottled leaves. Nasturtiums not only look spectacular but the flowers, leaves and seeds are edible too. Bees love the colourful nasturtium blooms, and caterpillars of the large and small white butterflies feed on the leaves.

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Being annuals, nasturtiums complete their lifecycle in one growing season.

How to grow nasturtiums

Nasturtiums are ideal for lots of different sunny spots around the garden, including pots. Climbing varieties of nasturtium can be trained up vertical supports and are great to twine through other plants too. Nasturtiums that are climbers can also be used as trailers – to spread across gravel or cascade down a slope or bank. Free-draining soil is essential for nasturtiums and, unlike many other flowers, they thrive on poor soils.

Nasturtiums: jump links

  • Where to grow nasturtiums
  • How to plant nasturtiums
  • How to propagate nasturtiums
  • How to harvest nasturtiums
  • Nasturtiums problem-solving
  • Types of nasturtium to grow
  • More on  growing nasturtiums:


    Where to grow nasturtiums

    How to grow nasturtiums - nasturtiums growing with geraniums and nemesia in a hanging basket
    How to grow nasturtiums – nasturtiums growing with geraniums and nemesia in a hanging basket

    Nasturtiums must have sun for at least half the day in order to grow well and do best in sites sheltered from winds. A free-draining soil is essential, and nasturtiums flower best in poor soils (that are low in fertility) as a fertile soil results in lots of leafy growth at the expense of flowers. Hence there’s no need to add fertilizer before sowing. Nasturtiums do well in gravelly or stony ground or growing on banks. In containers, mix two-thirds peat-free multi-purpose compost with one third fine gravel or grit, to reduce fertility and ensure good drainage.

    In this clip from Gardeners’ World, Monty Don arranges plants for a late summer display, with a dramatic purple-leaved Phormium cookianum ‘Black Adder’ in the centre, lots of magenta-flowered Cosmos bipinnatus ‘Dazzler’, and four Bidens ‘Hawaiian Flare Orange Drop’ cascading over the rim, alongside trailing nasturtiums, Tropaeolum majus ‘Cherry Rose Jewel’. He also advises on aftercare to keep the display at peak flowering through to late autumn:


    How to plant nasturtiums

    How to grow nasturtiums - sowing nasturtium seed
    How to grow nasturtiums – sowing nasturtium seed

    For best results, sow nasturtium directly where they are to flower, as they’re fast-growing and there’s no need to bother about transplanting. Sow the seed 1.5 cm deep into moist soil to speed germination, so water before planting if conditions are dry. The first seeds can be sown in mid-spring and you can carry on sowing until mid-summer to ensure flowers right up to the first frosts. Thin the seedlings to 30 cm apart.

    However, sowing in pot also works – simply sow one seed per pot and transplant outside when all risk of frost has passed.


    How to care for nasturtiums

    Nasturtiums are easy-care and need little maintenance. Plants growing in containers should be watered to keep the compost evenly moist, but not fed. Removing the dead flower heads of nasturtiums will encourage more blooms to be produced for a longer period.


    How to propagate nasturtiums

    Nasturtium seeds can be collected when ripe and saved to sow next year. In mild areas, nasturtiums are also likely to self-sow, so you may get seedlings springing up in future years. These can be easily pulled up if not wanted.


    How to harvest and use nasturtiums

    Nasturtium leaves, flowers and seeds are all edible. The flowers make a brightly coloured garnish to salads and other uncooked dishes. Nasturtium leaves have a peppery taste and should be picked when young to incorporate in salads. Nasturtium seeds can be used as a substitute for capers and should be picked when mature but still green, for pickling in vinegar.


    Growing nasturtiums: problem solving

    How to grow nasturtiums - blackfly on nasturtium leaf
    How to grow nasturtiums – blackfly on nasturtium leaf

    Nasturtiums are likely to attract large and small white butterflies (known as cabbage white butterflies) which lay their large greenish eggs on the leaf undersides, which hatch into caterpillars that eat the leaves. This can be useful to deter caterpillars from eating brassica crops but not desirable if you’re growing nasturtiums for flowers. The best method of control is to inspect plants regularly and squash the eggs or young caterpillars, or move them on to plants you don’t mind being eaten. Nasturtiums are also attractive to aphids, particularly blackfly. Again, by planting nasturtiums alongside bean crops you can lure aphids away from your crop, but you may not appreciate aphids on nasturtiums you’re growing for leaves and flowers. Spray them off with a jet of water or let ladybirds, hoverflies and lacewings remove them for you – all three lay their eggs on aphid colonies and their young quickly eat them up.


    Nasturtium varieties to grow

    How to grow nasturtiums - yellow nasturtium flower
    How to grow nasturtiums – yellow nasturtium flower

    A wide range of annual nasturtium (Tropaeolum) varieties is available by mail order from seed companies, or from garden centres. Choose from mixed flower colours or opt for individually coloured varieties to create coordinated planted schemes.

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    • Nasturtium ‘Alaska’  – flowers in yellow, orange and red are shown off against cream and green marbled leaves. Bushy, 30 cm high.
    • Nasturtium ‘Empress of India’ – crimson-red flowers and dark reddish leaves. 25 cm high.
    • Nasturtium ‘Milkmaid’ – Creamy-white flowers on climbing/trailing stems. 180 cm high.
    • Nasturtium ‘Paintbox Mixed’ – a mix of brightly coloured flowers that are more upward facing and hence visible than most. 30 cm high.
    • Nasturtium ‘Salmon Baby’. Bright salmon pink flowers. 30 cm high.
    • Nasturtium ‘Tip Top Velvet’. Dark red blooms that show off well against fresh green foliage. 30 cm high.
    • Nasturtium ‘Trailing Mixed’, ‘Tall Mixed’. Masses of orange, yellow and red blooms on long stems that can climb or trail. 180 cm high.