Tithonia (Mexican Sunflower) in Zone 5a & 5b

Tithonia rotundifolia

When to plant tithonia (mexican sunflower) in zone 5b

Zones 5a and 5b share the same average frost dates in our data, so this page covers both.

Method: Either: Start indoors for an earlier harvest, or direct-sow outside for less fuss. Tithonia (Mexican Sunflower) tolerates either.

Spacing: about 2 square feet per plant (square-foot-gardening spacing). Mature height: 4-6 ft.

Tithonia, better known as Mexican sunflower, is a fast-growing, heat-loving annual that produces vivid orange-red blooms on tall, sturdy stems late in the season, just as many other cut flowers are winding down.

How tithonia (mexican sunflower) fits zone 5's season

Zone 5b's frost-free window runs about 148 days, from May 10 to October 5. Tithonia (Mexican Sunflower) needs about 88 days from sowing to first harvest.

Good companions

No standout companions recorded yet for Tithonia (Mexican Sunflower).

Where to buy tithonia seeds

• Botanical Interests
• True Leaf Market
• Burpee
• High Mowing Organic Seeds

See why we recommend these suppliers →

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See it growing

Search YouTube for "growing tithonia (mexican sunflower)" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)

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Growing Tithonia (Mexican Sunflower) in USDA zone 5b: when to start seeds indoors, when to direct-sow, and when to expect a bloom.

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