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Plant of the Month: Marigold

African Fall Trials


Tagetes erecta Fall Variety Test

Latin name: Tagetes erecta
Common name: African marigold
Flowers: Baseball-sized double flowers
Mature size: 12”-30” tall by 12”-18” wide, depending on variety
Hardiness: Summer or fall annual
Soil: Well-drained 
Exposure: Full sun
Water usage: Medium 
Sources: Local nurseries or seed companies

The name marigold is derived from the name Mary, meaning "the Mother Ray," and the word gold, for the flowers’ variety of warm colors. When it comes to marigolds, pretty much everyone knows what plant you are talking about. There isn’t anything truly exotic or new about this plant. Surprisingly, though, there seem to be two camps of thought: you either love them or hate them. Reactions seem to be mostly related to marigolds’ fragrance.

We happen to like marigolds at the Dallas Arboretum. They are easy to grow, heat tolerant, and they come in wonderful shades of yellows, oranges and gold. They are especially appreciated in our garden during the late summer and fall months. Other than chrysanthemums, there just aren’t many plants that give exceptional fall color. Many years ago, Texas A&M Agriculture Extension extolled the value of “Mari-Mums” to everyone. Basically, they were telling us to plant African marigolds in the garden and just fib to our neighbors about them being mums. It really wasn’t a bad idea. African marigolds planted in fall out-bloom any chrysanthemum we’ve ever tried. They have huge flowers of pumpkin orange and autumnal gold, and they are cheap! So we wondered, if the big-flowered African marigolds were so great for us here in Texas for autumn color, which variety should we use? There are many to choose from. So we turned to the Dallas Arboretum Trial Gardens to sort out the best of the group.

We trialed 32 cultivars last fall and 34 cultivars this spring and summer. All of the varieties tested actually did very well for us, but we award our Arboretum Approved seal only to the best of the crop. Here are some of the varieties that really stood out:

• ‘Perfection’ series is a taller series, available in gold, orange, and yellow, that you can display in the back of your landscape. Or allow it to be the “thriller” in a container. ‘Perfection’ quickly reaches 30” tall by 15” wide. Keep this in mind when planting! 
• ‘Marvel’ series is perfect for the middle of your landscape or the border and is available in gold, orange, or yellow. Highlight ‘Marvel’ in your containers as your “filler.” ‘Marvel’ reaches 18” tall by 10” wide. 
• ‘Moonsong Deep Orange’ is the best choice if you like a slightly deeper orange with a larger flower. This cultivar is ideal used as that “filler” in a container, in the middle of your landscape, or as a colorful border. ‘Moonsong Deep Orange’ reaches 15” tall by 10” wide. This variety looks like pumpkins on sticks!

Marigolds are one of those plants that are easy to grow for any level of gardener, and they are especially great for kids. If you are new to gardening, try marigolds. They are easily grown straight from seed, and they grow fast. In our trials, marigolds have proven for several years that they love to bloom and that they require very little time or maintenance. To ensure success with gardening, establish your beds with good soil preparation and proper drainage, and always hand-water the first several weeks to allow roots to establish. Don’t give marigolds any shade at all. The biggest mistakes you can make are to overwater or give them less than full, blasting Texas sun. If you get spider mites on your plants, most likely it is due to one of these causes.

The best time to plant marigolds in the garden is during the last weeks of August or first few weeks of September. Even though they are often thought of as spring through summer flowers, they really perform much better from late summer up until frost. Use them to fill holes in your borders, add color to your fall display, and to mass plant. Plant directly into the garden from seed the last week of August, and you will have flowers by mid-September, right up until the first hard freeze. (Personally, we think they actually grow best seeded directly into beds.) If you plant your marigolds from 4-inch nursery containers, be sure to break open the root ball. Marigolds have huge root systems and can get so root bound that they won’t take hold in the garden otherwise. Well-drained soil in full sun, coupled with medium feedings of either a granular or a liquid fertilizer will allow them to establish quickly and bloom heavily throughout the season.

Many veggie gardeners plant marigolds around their gardens to deter insects with their strong fragrance. You must plant them in masses, but if nothing else, they will add a nice display of color around your veggie beds. To harvest from your yard, pick the flowers and add them to your salad. This will add a nice splash of color, but use sparingly at first! Marigolds can be an acquired taste. If you like dehydrating or drying flowers, marigolds are a flower for you. Some even create marigold ointments that aid in skin irritation relief. 
 
Marigolds are one of those plants that have many uses that make them attractive and fun for all levels of gardeners. If you visit The Dallas Arboretum Trial Gardens now, you can choose the marigold that you think would work the best for your gardening experience.