How to Grow Marigold Seeds

Grow Guide #2288
Family: Asteracea
Binomial name: Tagetes sp.
Life Cycle: Annual

This 'How to Grow' guide details everything a home gardener needs to know to plant, grow and care for Marigolds (Tagetes sp.).

When to Sow Marigold Seeds

Marigold is a warm season flower. Use the table below to identify the best time of year to sow marigold seeds in your climate.

  JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Cool
Temperate
Sub-Tropical
Tropical
Arid

Preparation

Marigold plants commonly self-seed in the garden. Self-seeding plants drop seeds onto the soil at the end of the season that may germinate and grow without help the following season. Choose a position where new plants will be welcome. If you do not want marigolds to become established in your garden, deadhead plants before they can drop seed or grow them in containers.

Marigold plants are best grown in full sun. Choose a location that will receive at least 6 hours of full sun each day.

Marigold plants need a well drained soil enriched with plenty of organic matter. Prepare soil by weeding it thoroughly, digging it over to loosen it and adding aged animal manure or compost. Keep the area free of weeds until planting. Learn more about preparing soil for planting here.

Marigold plants can be grown in containers. If possible choose a variety that’s recommended for container growing. Use a good quality potting mix and make sure your container is large enough for mature plants; a minimum of 20 litres is recommended for marigolds. During the growing season, keep in mind that container grown plants may need additional fertiliser to encourage healthy growth.

How to Sow Marigold Seeds

Marigold seeds do not require any treatment (eg soaking, stratification) before sowing.

Marigold seeds can be sown directly into the garden OR seedlings can be raised in trays or other containers and transplanted to the garden once established.

Sow Direct

  1. Sow seeds directly in the garden 5mm deep and 20-40cm apart.
  2. Keep soil moist but never wet or dry.
  3. Seeds should germinate in around 4-10 days at a soil temperature of 24-28°C.
  4. Young seedlings will need protection from pests, pets and weather until they are established.

Raise Seedlings

  1. Fill trays, punnets or jiffy pots with a good quality seed-raising mix, or use soil starter pellets.
  2. Sow seeds 5mm deep.
  3. Keep soil moist but never wet or dry.
  4. Seeds should germinate in around 4-10 days at a soil temperature of 24-28°C.
  5. Transplant seedlings to the garden once they have their first true leaves and are large enough to handle (usually 5-10cm tall).
  6. Plant out, spacing plants 20-40cm apart.

Marigold is a tender crop that’s sensitive to frost. Do not transplant seedlings or sow seeds outside until all danger of frost has passed.

Tip: Marigold seeds can also be sown in the less formal ‘scatter seed’ method. Simply roughen the soil, scatter seeds evenly over the surface, then smooth the soil over lightly to cover the seeds.

Optional: In cool climates marigold seeds can be sown indoors 6 weeks before the last expected frost. Grow them in a warm position with plenty of natural light.

How to Grow Marigold

Marigold plants may need watering during the growing season. Water when the soil is dry about 5cm below the surface (test this by scratching away a little soil with your finger). Water deeply in the early morning or late afternoon. Avoid watering the leaves of plants to avoid fungal diseases. Learn more about watering here.

If soil was well prepared no extra fertiliser should be necessary. In poor soil or to give your plants an extra boost, application of a high-potassium fertiliser or one formulated for flowering plants can be beneficial:

  • Apply slow release fertiliser at the recommended rate when transplanting or when seedlings are 5-10cm tall.
  • Apply liquid fertiliser at the recommended rate and frequency while plants are fruiting or flowering.

Optional: Pinch out the growing tips of marigold plants to encourage denser growth with stronger stems and more flowers. Using sharp secateurs or snips remove the top set of leaves, cutting just above a set of lower leaves.

Marigold plants should flower in approximately 80-90 days.

Deadhead marigold flowers regularly during the growing season. Using sharp secateurs or snips cut fading or dead flowers off just above a set of leaves. Removing old flowers regularly will encourage plants to produce more flowers. Learn more about deadheading flowering plants here.

Common Problems when Growing Marigolds

Like all plants, marigold is susceptible to some pests, diseases and other problems. Below is a list of the most common problems gardeners encounter when growing marigold plants:

  • Damping Off
    Damping off is caused by a fungal growth that transfers from the soil to seeds or tender seedlings. Seeds may appear not to germinate, or young plants start to rot when they emerge from the soil and become soft and mushy at the base before dying. Use new potting mix if raising seedlings, do not water foliage and avoid waterlogged soil. Read more about damping off here.
  • Powdery Mildew
    Powdery mildew is caused by fungal spores reproducing on the leaves of plants. First showing as white spots on leaves, affected areas can spread quickly to cover the entire leaf surface. While rarely fatal, powdery mildew can reduce yields. Water plants at soil level (not on leaves) to prevent spreading spores, allow good air flow between plants, remove affected leaves and if necessary spray with an appropriate fungicide or homemade spray. Read more here about powdery mildew here.
  • Slugs and Snails
    Slugs and snails are molluscs that feed on tender leaves and shoots, mostly at night, leaving slimy trails behind them. Control them by removing their hiding places, keeping free range poultry, collecting them by torchlight or by placing traps. Read more about slugs and snails here.

Browse Marigold Seeds

Marigold, African- Calando Mix
SOW SOON
SOW NOW 
SOW SOON

Marigold, African- Calando Mix

Packet 125 seeds

$1.75

Add
Marigold, African- Crackerjack
SOW SOON
SOW NOW 
SOW SOON

Marigold, African- Crackerjack

Packet 125 seeds

$1.50

Add
Marigold, African- Hawaii
SOW SOON
SOW NOW 
SOW SOON

Marigold, African- Hawaii

Packet 125 seeds

$1.50

Add
Marigold, African- Savannah Sun
SOW SOON
SOW NOW 
SOW SOON

Marigold, African- Savannah Sun