Guide to Planting and Growing Marigolds

Marigolds are beautiful annual flowers that are great to plant in the garden for a number of reasons. They attract pollinators and beneficial insects while at the same time providing benefits for companion planting. Marigolds are extremely easy to grow and you can save the seed from them each year to start again year after year. Here’s more about growing marigolds in the garden.

How to Plant and Grow Marigolds

About French Marigolds (Tagetes patula)

French marigolds are annual marigolds and will die back when the fall frosts arrive. You can start seeds for French marigolds indoors 6 to 8 weeks prior to the last frost date or direct sow in the garden after the last frost date. Pre starting indoors will get them to their blooming stage a lot sooner.

You can expect flowers to bloom in about 8 weeks from the transplant date depending on the variety. All marigolds are full sun plants so put them in a location that gets sunlight for the majority of the day.

French marigolds tend to be shorter plants that spread more horizontally allowing for good bed coverage. When designing gardens with marigolds use French marigolds at the front of the garden as a border plant that allows taller plants to grow behind it. Space them 8-10 inches apart and they will fill in together.

African Marigolds (Tagetes erecta)

African marigolds are a different species than French marigold. Despite the name, African marigolds original from South America. Which is also why they have other names like American marigold, Mexican marigold or Aztec marigold. African marigolds have larger flowers that are often doubled and can get very heavy on tall flower stalks. Some varieties can get around 3 to 4 ft tall. Think of them as a middle area plant for a garden bed.

Companion Planting with Marigolds

Companion planting is where plants with beneficial properties are used with other plants to aid in their development and growth. Marigolds are great for companion planting. When flowering marigolds attract cool beneficial predatory insects like lacewings, small parasitic wasps, hoverflies, and of course lady bugs. These beneficials are like mini warriors to fend off your garden from attackers. Marigolds have a strong scent and can repel larger animals like rabbits and deer to some extent. When planted in a ring around a garden marigolds also can create a barrier for damaging nematodes around plants. Marigolds also will repel aphids and whiteflies.

Nematodes are damaging soil pests that like to attack some of our favorite vegetable plants like tomatoes. Marigolds can act as a trap crop for some marigolds and have chemicals that can damage and repel them.

Interplanting Marigolds

To get the maximum benefit of companion planting marigolds in your garden interplant them with your other crops. Mix them together with tomatoes, peppers, eggplants, cucumbers, strawberries, squash, onions, or garlic. Avoid planting with beans and cabbage as they don’t get along and marigolds may actually reduce the growth of beans.

Starting Marigolds from Seed

Growing marigolds from seed is much more economical than buying plants to transplant. Packets of seed can be purchased for just a few dollars at most and typically contain 30 or more seeds per packet. A six pack of marigolds may cost you $3-4.

Materials Needed for Starting Marigold Seeds:

Marigold Seeds: Pick your favorite variety of marigold seeds. You can find different types, such as French, African, or signet marigolds. Here’s a few marigold varieties from Botanical Interests you could try (affiliate link).

Seed-Starting Trays or Pots: Use trays or pots with drainage holes to prevent waterlogged soil and promote healthy seedlings. I like to use 1020 seed starting trays then plant the seeds into small 3″ pots inside that are biodegradable. My pots are made of coir but you can also find peat or use soil blocking.

Seed-Starting Mix: Opt for a well-draining seed-starting mix to provide the ideal conditions for germination but potting soil will work just as well. Marigolds are not all that picky!

Watering Can or Mist Sprayer: Maintaining a consistent moisture level during is very important. A mist sprayer adds a little moisture without disturbing the seeds. If you are using 1020 trays you can bottom water the tray to keep the medium moist.

Plastic Wrap or Dome: Covering the trays or pots will help to keep moisture contained and reduce the need for watering.

Sowing Marigold Seeds

Growing marigolds from seed is extremely easy. Often I will just scatter sow them in the garden where I want them to grow. Some I’ll start in pots in 1020 trays so I can control exactly where I want them in the garden. How you grow your marigolds is up to you but here’s how to start them from seeds.

Prepare the Soil:

Fill seed-starting trays or pots with a well-draining seed-starting mix. Moisten the mix slightly.

Sow the Seeds:

Plant the marigold seeds on the surface of the soil. Marigold seeds are tiny, so a light covering (about 1/4 inch) of the seed-starting mix is sufficient. Tamp the medium down gently to get good surface contact with the seeds.

For Direct Sowing: If you’re directly sowing marigold seeds outdoors follow the same steps but sow the seeds directly in the garden soil after the last frost date. Make sure the seeds are covered with a thin layer of soil to protect them.

Moisten the Soil:

Gently water the soil using a mist sprayer or a watering can with a fine nozzle. Ensure the soil is evenly moist but not waterlogged. Remember that too much water can be just as bad as too little water.

Cover the Trays or Pots:

Place plastic wrap or a clear plastic dome over the trays or pots to create a mini-greenhouse effect. This helps retain moisture and warmth.

Provide Warmth and Light:

Marigold seeds germinate best in warm conditions. Place the trays or pots in a warm location, preferably with temperatures around 70-75°F (21-24°C). If you are planting in a cooler location you can utilize heat mats under your seed starting trays. I generally seed start in unheated areas like a garage which can be a lot colder than it should be for sowing seeds. Heat mats save the day!

Ensure that your seeds receive bright, indirect light. Grow lights can be very useful as their light won’t blaze down like direct sunlight.

Monitor Germination:

Marigold seeds should germinate anywhere between 4-14 days. Depending on the temperature they may take a little longer. Keep an eye on your trays/pots and remove the plastic cover once the seedlings emerge.

Transplant Seedlings:

Continue to monitor the seedlings until their first set of true leaves form. These will look different that the first two leaves that emerge. The first set of leaves are called cotyledons and they won’t look like marigold leaves but will be much more rounded. Once you have that first set of leaves you can transplant to a larger pot or directly into the garden.

Harden Off and Plant Outdoors:

If you aren’t direct sowing your plants outdoors you will likely need to harden them off before you transplant outdoors. This is just where you gradually acclimate them to the outdoor growing conditions. Start by putting them in a shady outdoor location then give them a little more time in the sun each day. Be sure to keep them watered throughout this process.

Where to Plant Marigolds

Anywhere you want that is a good well drained location in full sun. A little shade won’t be the end of the world but may reduce the flowering somewhat. Companion plant your marigolds with tomatoes, peppers or other vegetable plants or use in ornamental garden beds. Planting in pots works great too. Marigolds are very good flowers in a variety of circumstances. I would recommend avoiding double flower type marigolds and opting for the single ones. Single flowered marigolds are much better for attracting pollinators as they have better access to pollen.

A Few Tips on Growing Marigolds

• Pinch back stems when seedlings are 6-8 inches tall for bushier growth. Pinching terminated the terminal bud which triggers side growth along other branches.
• Regularly remove spent flowers to promote continuous blooming. Flowers want to make flowers and if you remove flowers you get more flowers! Funny how that works!
• Water regularly, especially in hot, dry weather, but you knew this already.
• Lightly fertilize once a month during the growing season. A balanced organic fertilizer is the best thing.
• Apply a layer of mulch for moisture retention and weed suppression.

Uses for Marigolds

Marigolds are not just simply great to enjoy in the garden but also can be used in bouquets or as dried flowers.

When the growing season is a few weeks from being over allow your marigolds to form seeds. Harvest the seeds from the flowers and save them to start again next year.

Varieties of Marigolds:

That should at least get you started to gardening with marigolds! They are definitely worth planting a few in your garden. I like to mix them with other pollinator friendly companion planting plants like basil, cilantro, oregano, and others.