Tithonia rotundifolia (Mexican Sunflower)

Article by Extension Master Gardener℠ volunteer Kathryn Copley

Mexican Sunflower is a low-maintenance annual that tolerates deer, drought, heat, and dry soil and has moderate salt tolerance. Showy in the garden, it is also a good cut flower.

It is fast-growing (3- to 6-ft. tall and 2- to 3-ft. wide) with plenty of orange-red 3-in. blooms that attract bees, butterflies and hummingbirds from mid-summer to fall.

Plant Tithonia rotundifolia in full sun in average, well-drained soils. Avoid rich soil or heavy fertilization, both of which promote excess foliage and weak stems. Pinch back plants to encourage sturdier, bushier growth. Sturdier plants are less likely to fall over but plants may need to be staked. Stems can be brittle, so shelter plants from strong winds if possible. Dead-head to prolong the bloom season.

Use this plant in the back of the border in cutting gardens, drought tolerant gardens and pollinator gardens. For a high-energy planting, use in mixed or annual borders with tall zinnias, coreopsis, and other flowers in hot colors. Or tone down the brilliant orange-red flowers by combining with purple flowers and larger plants with dark-colored foliage.

Mexican Sunflower has no serious insect or disease problems, but watch for slugs and snails.

• 'Torch' - the most commonly offered cultivar, winner of an All-American Selection award in 1951.
• 'Fiesta del Sol' - a shorter cultivar, growing about 3-ft tall.
• 'Goldfinger' - 2 to 2 1/2-ft tall with orange-gold flowers.
• 'Yellow Torch' - with apricot yellow-orange flowers.

Resources

• NC Extension Gardener Plant Toolbox: Tithonia rotundifolia (Mexican Sunflower)
• Home & Garden Information Center: Growing Annuals
• Wisconsin Extension Center: Mexican Sunflower Tithonia rotundifolia

By Kathryn Copley, Extension Master Gardener SM Volunteer, Brunswick County, NC. For more information on gardening in Brunswick County, please call the Brunswick County Cooperative Extension Office 910-253-2610