When to plant marigolds – for blazing color and cut flowers

Discover when to plant marigolds for fiery flowers that attract wildlife and fill vases all summer long

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(Image credit: Getty Images)

The flame-bright flowers of marigolds light up the backyard throughout summer and provide a steady supply of fresh cut flowers for the house. 

On top of that, these annual plants smell wonderful and lure beneficial insects that protect edible crops from predators. 

Easy to grow and available in bold, fiery shades of orange or gold marigolds are a welcome site among flower bed ideas, and our guide has the lowdown on when to plant them. 

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(Image credit: Getty Images)

When to plant marigolds

You can grow marigolds from seed or put in ready-grown plants, and there are two main types: Calendula and Tagetes. Calendula are better for cutting, but both can be used for companion planting in the vegetable garden or for ornamental color. Our guide has details on when to plant marigolds of either type.

‘Plant marigolds in pots or use them to fill in holes in the summer perennial bed,’ says Ohio-based garden designer Ethan McGory. ‘They are very productive and easy to grow from seed.’  

When to sow Calendula marigolds

Being a hardy annual, pot marigold (Calendula officinalis) can be sown under cover (in a greenhouse or on a windowsill) or direct into the soil outside in March, April, or May for summer flowers the same year. Alternatively, they can be sown under cover or direct into the soil outside in August or September for flowers the following year. 

Sow in well-drained soil in sun, at half an inch (1cm) deep. Thin the seedlings to 12in (30cm) apart, protect them from slugs, and water regularly (especially in dry, hot weather). 

When to plant Calendula marigolds

Pot marigolds (calendula) can be bought as bedding plants from plant nurseries or as seedlings via mail order in May or June. Plant in well-drained soil or containers in sun. 

When to sow Tagetes marigolds

The answer to when to sow Tagetes marigolds depends whether you’re doing so indoors or outdoors.

‘The best time to sow tagetes indoors is six to eight weeks before the last frost at a temperature of 70 to 75°F (21 to 24°C),’ says Kelly Funk, President of Park Seed. ‘Expect germination in five to seven days. African marigolds (Tagetes erecta) can be started indoors two to three weeks earlier than the French (T. patula) as they take longer to initiate flowering.’ 

In temperate climates (such as the northern US and the UK), ideal sowing time indoors (on a sunny windowsill or in a heated greenhouse) is February for traditional, old-fashioned African marigolds (such as Tagetes erecta ‘Park's Whopper); while more contemporary French marigolds (such as T. patula ‘Linnaeus Burning Embers) and signet marigolds (such as T. tenuifolia ‘Lemon Gem) can be sown in March or April. 

‘Seeds can be sown outdoors after danger of frost has passed in your region,’ says Kelly. In temperate climates (such as the northern US and the UK), this is May and June. 

Sow these half-hardy annuals into moisture-retentive, well-drained soil in sun, around 10in (25cm) apart. ’When sowing outdoors, sow at a depth that is four times the width of the seed,’ advises Kelly.  

When to plant Tagetes marigolds

Buy and plant Tagetes as ready-grown bedding plants in May or June. Use them to brighten gaps in borders, in moisture-retentive, well-drained soil in sun. Alternatively, plant them in pots or windowboxes. 

If you have grown your own plants from seed, harden them off before planting outside – for example, by placing them in a cold frame or by sitting the plants outside during the day for a week covered with fleece, then gradually remove the fleece. 

Do marigolds come back every year?

Calendula and Tagetes are annuals, so they only live for one year. However, if sown early and then deadheaded or regularly cut for the vase, marigolds will flower for months, sometimes from May to November. Calendulas will often self-sow, giving you more flowers the following year. 

What should marigolds not be planted near?

There aren’t many plants that marigolds shouldn’t be planted near but avoid planting them near beans – a study published in Environmental Entomology showed French marigolds inhibited the growth of snap beans. 

Hazel Sillver

After experience in the fashion industry, Hazel became a beauty and wellbeing journalist, and worked for The Ecologist as Green Living Editor. During a period of injury, she studied horticulture and garden design, and went on to work as a gardener and write about gardening for national newspapers, including The Guardian. Today, she enjoys regularly contributing to print and online magazines, including Amateur Gardening and Homes & Gardens.