Tithonia, aka “Mexican Sunflower”

Perhaps no other plant in the garden tells the story of Wondrous Gardening more than Tithonia rotundifolia. One of the few annuals found in my garden, Tithonia is a pollinator powerhouse.

I start Tithonia by seed under grow lights in March, and set out in the garden in mid-May after the last chance of frost. Once in the ground, seedlings virtually explode with growth and vigor, quickly reaching 4 feet tall by June and towering to 6 feet by August. Yes, you’ll need a big, sunny space if you want to really appreciate Tithonia. By end of summer, one plant can exceed 7 feet in height and 4 feet in width. Plants develop strong lateral branching and produce delightful, orange daisy-like blooms.

In southern NH, the “Tithonia Show” begins around July 4th and doesn’t end until late October, or whenever we have our first killing frost. While other annuals and perennial blooms have come and gone, Tithonia just keeps on producing hundreds of blooms which are irresistible to bees and butterflies. Its late-season hardiness ensures a vital food source for pollinators as other nectar sources have dried up.

  • Plant type: annual, native to Mexico and Central America

  • Growing Conditions: full sun, tolerates average to poor soil and hot, dry conditions

  • Size: reaches 84" in height;

  • Spread: 3-4', branching from central stalk, non-invasive

  • Bloom: early July through October in Zone 5b

  • Maintenance: low-maintenance show-stopper

  • Biodiversity: frequented by bees, butterflies & hummingbirds

  • Pairings: rudbekia, veronicastrum and alliums

  • Location: place in an open bed, unencumbered by man-made structures where it can be accessed from all sides by pollinators

  • Pests: none

mid august in the mailbox garden

One tithonia plant dominates my mailbox garden which is in full sun. I interplant annual seedlings with Veronicastrum which obediantly bows out just in time for the Tithonia seedling to reach gigantic proportions and take over the role of sustaining native pollinators.

vital food source for monarchs

By end of summer, my one Tithonia plant is massive and still producing consistent blooms. Bees and butterflies spend the day flitting between this plant and Verbena Bonariensis, planted a few feet away. Dried seed heads are permitted to mature before harvesting for next year’s garden.

The Big Little Garden only has one suitable location for Tithonia, and that’s down by the street in what I call my “Mailbox Garden”. It’s full sun, dry and hot. Perfect growing conditions for this hardy annual. Beautiful, easy care and a pollinator magnet - what else do you need?