Mexican Sunflower, How to Sow, Grow, Care for, with Images and Guide


Sunflower Guides /

If you have space in your yard or a large pot to grow a Mexican sunflower, then I’m sure you’ll have as much pleasure, as I have, in doing so.

The bright red and orange varieties attract an abundance of butterflies and bees. And if you reside where hummingbirds live you’ll be pleased to know that they love to visit these vibrant sunflowers too.

So what is a Mexican Sunflower? The Mexican Sunflower has bright orange or red flowers and grows 4 to 6 feet tall and 3 to 4 feet wide. It’s multi blooms grow on stems coming off a bushy central stalk. The flowers are daisy-like and measure 3 inches in diameter. Ideal for back borders. And loved by pollinators.

Here’s more information about this beautiful sunflower, what its uses are, and how to grow and care for them.

Scientific Name and Classification of Mexican Sunflowers

Kingdom: Plantae > Clade: Angiosperms > Clade: Eudicots > Clade: Asterids > Order: Asterales > Family:Asteraceae > Genus:Tithonia > Species: T. Diversifolia.

Botanical Name

Tithonia Diversifolia

Common Name

Mexican Sunflower

What the Mexican Sunflower Looks Like 

Mexican Sunflowers are vigorous and fast-growing. They can grow 4 to 6 feet (60 to 75cm) tall and 3 to 4 feet wide in a season. Each plant has a large central stem that branching stalks come from in a somewhat chaotic, albeit charming way. 

The leaves are dark green, large and a cross between a triangular and heart shape. These leaves are serrated slightly coarse. To the touch, the leaves and stems have a fuzzy, soft covering, the underside of the leaves are hairy too.

Monarch butterfly on a mexican sunflower

Mexican sunflowers start flowering from the middle of summer until the frosts of autumn. Each branching stem produces a single 3 inch (7.5cm) flower of bright orange or red petals surrounding a golden yellow disc. 

Like most sunflowers, the petals fall, but the golden center disc will remain a while longer. It carries on attracting pollinators and eventually will produce seeds for the following season. 

Where to Place Mexican Sunflowers and Their Uses

Mexican Sunflowers are best suited at the back of borders and in large open spaces. They are prolific at growing. They grow tall and their branches spread out at a vigorous rate. 

That’s not to say you can’t grow it in a large pot, as I have. Because I contained it, it didn’t grow too big, and I still had the beauty of this sunflower, and all the butterflies it attracted throughout my summer.

You can cut The Mexican Sunflower blooms, just as they are opening, and display them in vases. This will encourage the plant to produce more buds and blooms to enjoy. 

Another use for the Mexican Sunflower, and with most sunflowers varieties, is they will clean and cleanse toxins out of the soil. Leaving a better quality of soil for you to start growing again.

Pick Your Mexican Sunflower Seeds

If I’ve enticed you into liking the idea of growing Mexican Sunflowers, and you can’t find the seeds locally, I’ve found them for you on Amazon.

Mexican Sunflower Seeds

Knowing we can get the seeds for sowing, let’s get growing

Basic Gardening Terms

Let’s start with a few gardening terms and what they mean for the Mexican Sunflower.

  • Half-Hardy Annual.  The Mexican Sunflower is categorized as Half-Hardy means it cannot withstand the cold weather, so the seeds must be sown indoors when it is still warm, or outside when the fear of frost has passed. Annual means it will grow, live and produce seeds one year.  
  • Potting On. To divide seedlings or plants that have outgrown their pots, into their own pots so they have further room to grow and mature.
  • Thinning out. If a number of seedlings are growing in the same growing site, and are growing too close together, remove the other plants and space them out accordingly, to give more room to grow.
  • Hardening Off. 2 weeks before the danger of frost has gone, gradually accustom seedlings that have been grown indoors to the outside world. Do this by placing them out each day for several hours, then bring them in at night. For the second week increase the hours out, until they are out all night and ready to be planted out.
  • Planting Out. Planting seedlings or plants in their growing sites. Tender sunflower seedlings need to be hardened off before planting out when all danger of frost has passed.
  • Dead Heading. The Mexican sunflower grows multiple heads throughout the season. Removing the deadheads encourages new buds and flowers to grow.
  • Companion Planting. Sunflowers can be planted alongside other flowers, herbs, and vegetables. This helps to attract pollinators and good bugs to help prevent infestations and diseases. I’ve written an article about the best companion plants, and what not to plant next to sunflowers. I hope you find it helpful.  

How to Grow Mexican Sunflowers

Most sunflowers are easy to grow, and the Mexican Sunflower is no exception, it’s easy to grow too.

If you’ve bought a packet of seeds, with a few instructions on the back, or been gifted seeds from a friend, here are answers to questions about how and when to plant them. And the aftercare they need.

When to Plant Mexican Sunflower Seeds

There are 2 ways you can start seeds off. The first is to sow seeds in pots inside during the middle of spring.

The second is when all fear of frost has gone. Sow straight outside into their well prepared, sunny growing site.

So, let’s start with growing them indoors. Heres what to do…

How to Grow Mexican Sunflowers Seeds in Pots Inside.

In the middle of spring, about 4 weeks before the last frost has gone, fill small clean pots with clean compost, or soil and water them.

Place 2 seeds on the surface of the moistened soil and gently push them into the soil so they are just covered up.

Place the pots on a sunny window sill, or in a greenhouse and keep the soil damp. When the seedlings have grown their second true leaves, ease the plants out of their pots and gently separate each plant at its roots. 

What the Mexican Sunflower seeds, seedling, and young plant look like

Replant into separate pots, with more soil. Place them back in their sunny place and keep them moist with water.

After hardening off your seedlings, and when all fear of frost has passed, plant on your Mexican Sunflower seedlings into a sunny, well prepared, well-drained, weed-free growing site, or into large pots. 

If the soil you have is poor, dig in some slow-release plant food, or add a little liquid fertilizer when you water them.   

Mexican Sunflowers grow quick and bushy, so distance your seedlings about 36 inches (90cm) between each plant.

This gives them room to grow, and air to circulate around each plant. This will give it a chance to fight off diseases and gives good bugs room to visit and help protect the plants for you.

Keep your Mexican Sunflower well watered, try not to let them dry out or stand in a puddle.

As the flowers appear, cut them for display, or deadhead them. This will encourage new buds and flowers to appear.

How to Grow Mexican Sunflower Seeds Outside

Mexican Sunflowers need a sunny place to grow. Prepare your growing site a few weeks, or a month before you want to start sowing your seeds. This would be a good time to dig in any organic or leaf mulch you’ve gathered throughout the winter months.

Sunflowers can tolerate growing in bad quality soil, but if you still feel it is poor quality, then dig in some slow-release fertilizer, or use liquid plant feed once a week.

When all fear of frost has passed, water the growing site and place 2 to 3 Mexican Sunflower seeds onto the surface of the soil where you want your plants to grow. Gently push the seeds into the soil, so they are just covered up. 

Protect your seeds with netting or wire mesh to stop critters digging them up and feasting on them. 

When your Mexican Sunflowers seedlings start to appear and have grown their second true leaves, leave the strongest in place and thin out the rest to about 36 inches (96cm) apart.

Water them in, and if you feel your local wildlife wants to munch on them, protect them.

If you have too many seedlings left over and haven’t the heart to dispose of them, pot them up and gift them to family, friends, and neighbors. 

How to Care for Your Mexican Sunflower

Mexican Sunflowers, as with many sunflowers can withstand a bit of drying out, but as a rule, I’d advise keeping them well watered.

Try to avoid overwatering and don’t leave them in a puddle. Water gently at the base of the plant, so not to dislodge the soil around the roots.

Keep the area around your sunflowers weed free. Weeds will grow fast and suck all the water and nutrients away from your plants.

If weeds are a big problem, use mulch, or weed prohibiter to keep in moisture, whilst keeping weeds at bay.

Watch out for pests and problems. Gather up pesky creatures as soon as you see them. Such as cutworms, snails, slugs, and caterpillars, and put them in another area. 

Cut away any diseased or grub infested leaves and discard them. This will stop the problem from spreading to other plants.

mexican sunflower (post)
A Mexican Sunflower in all its glory

Harvesting Mexican Sunflower Seeds

Because the Mexican sunflower produces a multitude of blooms and attracts an abundance of pollinators, they also create a whole lot of seeds.

The seeds come after the flower has died back. They are dark greyish in color and triangular shaped.

Mexican Sunflower seeds are very easy to collect. Hold the dried flower in your hand and gently brush and pull your fingers over the seeds, they will loosen and fall out into your hand.

image of this coming soon

I usually collect the amount I need to plant the following year. I also collect enough to give as gifts for my family and friends too. The rest I happily leave for the birds and wildlife to munch on at their leisure.

How to Store Mexican Sunflower Seeds

Remove any debris from the seeds such as plant matter, dried leaves, and stalk. Clean the seeds and air dry thoroughly.

You can store the seeds in sealed paper bags, envelopes, sealed plastic bags or containers, or in a sealed tin.

Top Tip: Remember to write the name and date of your seeds on what you’re storing them in. Store them in a dry place, away from the clutches of wildlife.

Enjoy the fruits of your labor when you plant and grow them next year.   


Take Away Mexican Sunflower Planting Guide and Chart

mexican sunflower copyright version (Featured)

Mexican Sunflower take away planting guide and chart

This is a summarized chart of how to sow, grow, and care for Mexican sunflowers. Please note, this watermarked version is free to download. it is for your own personal use to print, pin or post. and not for ….commercial gain or usage.


Pick Your Mexican Sunflower Seeds

Mexican sunflowers attract a multitude of butterflies, bees and other pollinators. If you can’t find the seeds locally, I’ve found them for you on Amazon below, as well as a link to my unwatermarked planting guide download as a gift for yourself – or another sunflower lover!

Mexican Sunflower Seeds

Why Not Add My Mexican Sunflower Guide
Without The Watermark

Helpful Sunflower Guides and Articles

I’ve written many articles that will help you choose, sow and grow the most gorgeous sunflowers. Most have quick and easy to use take away diagrams, guides, and charts for you to download, pin, post or print out. Here they are, I hope you find them helpful. 

31 Most Wonderful Sunflower to Grow. With Height Guide

How to Grow Amazing Sunflowers

Do Sunflowers Need a Lot of Water

Why are My Sunflowers Drooping, Wilting, and Falling Over

The Best Sunflower Companion Plants, Vegetables and Flowers

My Conclusion

Mexican sunflowers may bush out and take up more space than a single stemmed, single-headed iconic sunflower, but that’s never stopped me enjoying them. They seem wild and magnificent all at the same time.

They attract more butterflies and bees than most sunflowers I’ve grown and look stunning as cut flowers arranged in my vases. They’re easy to grow and can be contained in a large pot, so I can place it where I want it. 

The Mexican Sunflower brings me so much joy throughout my summer. And if I’ve given you good reason to grow some too, I hope they bring you as much joy as they do me.

Leave a Reply

Your email address will not be published. Required fields are marked *