Melampodium is usually planted as a nursery-grown container plant or from seeds sown directly into the garden, as soon as the danger of frost has passed. Like many annuals, it is very fast-growing; even when planted from seed, it reaches flowering maturity within six to eight weeks. The other bit of good news is that melampodium also won’t require a significant amount of pruning or deadheading. This is a low-maintenance plant that will continue to blossom on its own up until the first frost of the year. In many locations, melampodium will self-seed, so you can enjoy these flowers year after year.
Light
The melampodium plant will grow best in full sunlight (at least six hours daily), as this will encourage optimal flower growth and discourage the flopping that can occur when plants grow leggy in shady conditions.
Soil
This plant is native to areas with rocky soil, so it is well suited for nutritionally poor soils. But it will grow well in any well-drained soil, provided it is not overwatered.
Water
Although it is a drought-resistant and heat-tolerant plant, melampodium will grow best with regular watering—1/2 to 1 inch per week is suitable. But just be sure to allow the soil to dry out slightly in between waterings, as the plants don’t respond well to soggy conditions.
Temperature and Humidity
These are truly warm-weather plants. Once they’re established, melampodiums are drought tolerant and able to withstand the hottest temperatures with ease. Despite its toughness, melampodium is susceptible to growing powdery mildew when planted in certain humid areas. Proper sunlight can help prevent this problem, but if you do see mildew growing, pruning infected areas can prevent spreading.
Fertilizer
To keep your melampodium blooming all season long, consider adding a slow-release fertilizer or a general-purpose liquid fertilizer to your soil. This is most likely to be of benefit it poor, rocky soils. In rich garden soil, these plants often do fine with no feeding whatsoever.
Types of Melampodium
There are two common annual species of the Melampodium genus cultivated as garden plants: M. Divericatum (butter daisy), and M. leucanthum (black-foot daisy).
M. Divericatum and Cultivars
The native species is a 12- to 24-inch plant with golden orange petals and darker orange centers. In addition, look for these popular cultivars:
´Derby´ has golden-yellow flowers and grows to about 12 inches in height.´Jackpot Gold´ has darker golden-orange flowers, about 2 inches across. It is also a relatively short cultivar, topping out at 12 inches.´Lemon Delight´ has flowers that are bright lemon yellow. It grows 12 to 24 inches tall.´Medallion´ is a large cultivar, growing 24 to 36 inches, with golden yellow flowers.´Million Gold´ is a compact, 10-inch plant with bright yellow flowers.‘Showstar´™ is a 14- to 24-inch plant with golden yellow blossoms.
M. Leucanthum
Know commonly as black foot daisy, Melampodum leucanthum is a bushy plant with small white daisy-like flowers and narrow, grayish-green leaves. A native of North America’s Sonoran Desert, it is a favorite rock garden plant for native plant enthusiasts.
Pruning Melampodium
This is a self-cleaning plant that needs no deadheading to continue producing flowers for the entire season. That said, you can clip off spent flowers if you want to limit the plant’s habit of self-seeding. At the end of the growing season, you can pull the plants from the ground, or leave them in place for the benefit of finches and other birds that like to eat the seeds.
Propagating Melampodium
Like many annuals, melampodium is best propagated by seeds—either purchased or collected from dried flower heads. Vegetative propagation, such as rooting stem cuttings, is possible but usually not necessary, since this plant is so easy to grow from seeds (see below). It is also quite easy to transplant volunteer seedlings that spring up in the garden from melampodium plants that self-seed.
How to Grow Melampodium From Seed
The seeds for melampodium are found clustered in the flower centers. Once spent flowers have dried, you can collect these seed heads and store them indoors until you’re ready to plant them. Crush the seed heads to separate the plentiful seeds. They can be direct-sown into the garden after all danger of frost has passed in the spring, but for earlier flowers, start the seeds indoors seven to ten weeks before the last frost date. Seeds will germinate in one to two weeks if planted 1/4 inch deep in standard potting mix and kept at 68 to 86 degrees Fahrenheit in a bright location. These plants will readily self-seed, so you may find that melampodium reliably returns year after year without any need for replanting. Learn to recognize the volunteer seedlings so you don’t mistake them for weeds.
Potting and Repotting Melampodium
Since the melampodium plant likes dry conditions, it makes a fantastic container plant. Just be sure to initially plant them a light, well-drained potting mix, and be wary of overwatering. Although many garden plants require more frequent watering when grown in pots, melampodium will be fine with once-a-week watering. Any pot material will be fine but make sure the container has good drainage. Repotting is not necessary, as these are annuals that will be discarded at the end of the season.
Overwintering
These plants are generally just pulled from the garden and discarded at the end of the growing season, but you can also leave the in place into the winter for the benefit of seeds that will be eaten by birds or which will fall into the garden to sustain the colony by self-seeding.
Common Pests & Plant Diseases
These plants are not susceptible to any notable insect problems, but they can be prone to powdery mildew in hot, humid climates. Give the plants plenty of space to improve air circulation and prevent this fungal disease.
How to Get Melampodium to Bloom
Both species of Melampodium will typically bloom from late spring until frost. If they fail to bloom as expected, it’s almost always a matter of needing more direct sunlight. These plants will not bloom in deep shade, but otherwise, flowers are almost guaranteed.
Common Problems With Melampodium
The only notable problem with melampodium is its tendency to get leggy and flop over. This may happen in shady conditions, as stalks are struggling upward to get enough sunlight, but flopping can also be a problem in hot, sunny locations, where soil can become so dry that it fails to support the stalks. In these cases, staking the plants may be necessary. This daisy will attract butterflies, bees, and other pollinating insects, and its seeds provide food for goldfinches and other songbirds. Smaller varieties are great for container gardens.
