How to Grow Marigolds

Marigolds are undeniably eye-catching flowers, so beautiful and bold that anyone would be thrilled to have them in their flower garden! With their stunning orange and yellow blooms and strong scent, marigolds are also one of the best companion plants for your vegetable gardens, deterring pests from attacking! Perfect for your flower beds and vases throughout the house, these cut flowers will liven up any space!

If you’re wondering how to grow these flower seeds, our Mr Fothergill’s guide has plenty of information to help you along the way. From when to plant marigold seeds to how to harvest marigold flowers, you’ll find everything you need to know right here.

Marigold Classification

Family

Asteraceae.

Genus

Tagetes patula, Tagetes erecta & Tagetes tenuifolia.

Lifecycle

Annual but prone to self-seed.

Marigold Varieties

With over 50 varieties of Marigold available, there are plenty of options to suit you and your garden aesthetic. Some popular varieties include:

• French (Tagetes patula)
• African (Tagetes erecta)
• Signet (Tagetes tenuifolia)

In order to give your marigolds the best chance of showing healthy, vibrant blooms, we recommend taking the time to prepare your soil for planting.

Marigolds thrive in well-draining fertilised soils, in either full sun or just partial shade. Be sure to keep your soil free from weeds to give your marigolds the best chance at healthy growth. Marigolds do, however, suffer in tropical climates due to the wetter seasons.

Just these simple steps will go a long way when it comes to setting the foundations of initial growth for your marigold seeds.

When to sow marigold seeds

Let’s start with how to sow marigold seeds. Wait until your flower bed is nice and warm in late springtime before sowing your marigold seeds. Marigolds tend to flower within around 8 weeks, meaning you could be witnessing gorgeous blooms by the end of spring or early summer!

How to grow marigold seeds

When it’s time to start growing, sow your marigold seeds about 20cm apart and 5mm deep in your soil. Whilst they don’t like being waterlogged, you should make sure they’re nice and moist leading up to germination! Germination typically takes between 4 and 10 days, so you shouldn’t have to wait too long to see progress for your marigolds. 

Feel free to add more organic mulch as the weeks pass to give your marigold seedlings that extra little bit of nutrition.

How to sow marigold seeds indoors

You do, of course, also have the option to sow your marigolds in trays or containers indoors before transplanting your seedlings outdoors when the weather is suitable. 

After sowing your seeds indoors, you’ll eventually need to transplant them outdoors! You’ll know the perfect time to plant your seedlings when they have their first true leaves and stand between 5 and 10cm tall. When it comes to planting, handle your seedlings delicately and space them around 20-40cm apart in their final growing position.

One of our main pieces of advice to follow when planting seedlings is to make sure you completely avoid the frost. Just be sure to sow your seeds indoors around six weeks before the last expected frost in order to time their transplanting perfectly. 

As much as it’s important not to overwater your marigolds, you should keep an eye on their moisture. If it seems that the first couple centimeters of soil is dry, give your marigolds a light watering. Excesses of water can lead to root rot, affecting the health of the entire plant. 

To keep your marigolds nice and bushy, be sure to deadhead your flowers. This means that the plant can put all of its energy and nutrients towards strengthening future healthy blooms rather than creating seedheads out of dead flowerheads. 

Pests and Diseases

Something to look out for is fungal diseases like powdery mildew, which can come as a result of high humidity. You can avoid this by making sure your seeds are spaced out when sowing to encourage airflow around your plants. It could also be beneficial to remove your plants’ lower leaves to further increase the airflow around your marigolds.

Who wouldn’t want to display these gorgeous blooms around their home? When it comes to harvesting, there’s no need to pull up your plants - they make for stunning short-stemmed bouquets! Just cut the stem near the ground and remove any unwanted foliage before displaying them in a vase around your house. 

Companion Plants

Marigold flowers can benefit the growth of a whole variety of plants, including herb seeds and vegetable seeds! Certain scented varieties of marigolds are perfect for deterring insects when bordering vegetable gardens. However, this quality isn’t as present in newer hybrid breeds of marigolds. Species like French marigolds can act as a natural pesticide even after the plant is long gone!