Marigolds are a very popular group of plants, but not all marigolds are created equal.
In fact, there are approximately 46 plants referred to as marigolds that aren’t actually marigolds at all.
One of the genera most frequently referred to as marigolds is Calendula, most notably Calendula officinalis, better known as the common marigold or pot marigold.
But while calendulas share many similarities to true marigolds, they also have some important differences.
Depending on your preferences, these differences may be negligible or highly important.
What’s The Difference Between Marigolds And Calendulas?
The term “marigold” is actually about the Virgin Mary, referring to how the generally golden blooms of many plants resemble a halo.
Here are some of the key differences between calendulas and true marigolds.
Calendulas make up a genus of between 15 and 20 different species.
Tagetes (the true marigolds) is a genus of approximately 50 species.
A third genus, Dimorphotheca, has 20 accepted species and are all but two plants commonly referred to as cape marigolds.
All three belong to the Asteraceae family, but Calendula and Dimorphotheca are part of a tribe called Calendulae.
Calendulae plants are native to Africa and parts of southern Europe, whereas Tagetes is native to the Americas.
Calendulas contain a resin that makes them sticky to the touch.
Their leaves are long, rounded, and hairy, and the seeds are brown and crescent-shaped with little ridges on the outside.
These plants generally grow no taller than 24” inches, with flowers that vary from one species to another but tend to resemble those of daisies.
They also have a pleasant scent to most people.
However, Tagetes are very different.
Their own long leaves are serrated and smooth.
There’s no stickiness when touching them, and the blooms are densely packed, making them more closely resemble a squashed pom-pom.
Depending on the species, marigolds can range from 6″ to 48” inches tall.
Also, these plants are a bit more pungent, with some species being worse than others.
The seeds of true marigolds are straight and black with white tips.
Calendulas and marigolds are cherished for their flowers, bringing many benefits both in and out of your garden.
However, there are some differences even here.
Calendulas, for example, have edible flowers, once a staple of English and Dutch cuisine.
Known as poor man’s saffron, the petals have a mildly sweet taste with just a touch of bitterness that becomes stronger if the petals are dried out.
The petals are also traditionally used as a food dye.
Meanwhile, the resin has been cherished for medicinal purposes and is used in many folk remedies.
The plants even have spiritual and religious values.
Meanwhile, marigolds aren’t exactly edible, with some being more edible than others.
Tagetes lucida, for example, is often used as a substitute for tarragon.
Tagetes minuta is a major ingredient in a popular South American potato dish where it replaces the need for several herbs and spices.
Tagetes erecta is used as a food coloring, while Tagetes minuta is used in perfumes and as an essential oil.
Be warned that all true marigolds contain toxic substances that can be harmful to pets and may cause some symptoms in humans if you use the wrong species or too much of it.
But these two genera are also both beneficial companion plants in the garden.
Both attract pollinators and other beneficial insects, with calendulas and Tagetes erecta being the best at this task.
All members of the Tagetes genus can deter harmful nematodes.
Depending on the scent of marigolds, they can also repel several other pests, with calendulas repelling several caterpillars such as the tomato hornworm and true marigolds sometimes being pungent enough to chase away rabbits.
Calendulas are also excellent sacrificial plants for certain pests, drawing their attention away from more important members of your garden.
Another important distinction is that true marigolds tend to be tender perennials almost invariably grown as annuals.
Calendulas, meanwhile, are perennials in zones 9b to 11 but can also be grown as annuals further north.
Both are capable of self-seeding.
You’ll get calendula blooms stretching from May into early fall, whereas marigolds will bloom as early as 8 weeks after planting and will continue to bloom throughout the summer.
Some Final Notes
At the end of the day, these two genera have different appearances and smells, making them easy to tell apart once you know what to look for.
However, their care requirements and benefits in the garden are nearly identical so you can use the two pretty much interchangeably.
The only exception to this rule is if you want to use them in cooking.
Calendulas are all equally edible, but you must be careful with what species of Tagetes you use and ensure children and pets don’t munch on them.