As the chill of Ontario’s winter finally starts to give way to the warmth of spring, I’m already thinking ahead to the next season of dried flowers. One of my absolute favorites to grow and harvest for my dried flower arrangements is the strawflower (Xerochrysum bracteatum). Known for its papery, vibrant petals and excellent color retention when dried, the strawflower is a true gem for any farm or garden.
Strawflowers are native to Australia, and while they thrive in warmer climates, they can absolutely be grown here in our colder Ontario environment with a little care and attention. Here's my personal guide for growing strawflowers from seed, and how I get them to thrive in our unpredictable Canadian climate.
Start with Fresh Seeds for Best Germination
When it comes to growing strawflowers from seed, fresh seeds are essential for the best germination rates. I’ve tried using old seeds in the past, but I’ve learned that they just don’t perform as well. Fresh seeds ensure that you get the best results, and since strawflowers germinate easily, you'll want to give them the best possible start.
Sowing Strawflower Seeds: A Light Touch
Strawflowers need light to germinate, which means sowing the seeds on the surface of the soil without covering them. I use a 72-cell tray for my seedlings—it’s the perfect size for these little guys. The soil should be a wet starter mix, but not soggy—keep it just damp enough to encourage germination without drowning the seeds. A light misting with a spray bottle works best for this, as it ensures the soil stays moist without disturbing the small seeds.
Germination: Keep It Moist, Not Wet
After sowing, you’ll want to keep the tray in a warm location (around 18-21°C or 65-70°F). Germination typically takes around 7-14 days, depending on the temperature. I use a misting bottle to keep the surface lightly damp, but it’s critical to avoid too much water, as strawflowers don’t like being waterlogged.
Once the seeds start to germinate, it’s time to change up your watering technique. I prefer bottom watering by placing the tray in a shallow pan of water for about 20-30 minutes. The soil will soak up the moisture from the bottom, which promotes better root development. Afterward, I dump out any excess water and let the top of the soil dry before I water again. This helps avoid any stagnant, soggy soil, which can lead to mold or root rot.
Ventilation Is Key to Healthy Seedlings
In my early years of farming, I learned the hard way that ventilation is absolutely critical. My setup didn’t have enough airflow, and I ended up with trays that stayed too wet for too long. This created the perfect conditions for algae to form on the soil surface. To avoid this, make sure your seedlings have good airflow—especially as they begin to sprout.
For my grow lights, I use blue and white light spectrum to encourage vegetative growth, and I avoid using red light, as it promotes flowering, which I don’t need at this stage. Keep the lights about 6 inches above the seedlings, and make sure they have enough space between the light and their leaves to avoid sunscorch or crisping, which I’ve also struggled with when the seedlings got too close to the lights.
Hardening Off and Transitioning to the Greenhouse
Once the temperatures start warming up, I begin hardening off my seedlings by gradually introducing them to outdoor conditions. I start by moving the trays into the unheated greenhouse during the day, but I make sure they’re first in a shady spot. Slowly, over the course of a few days, I increase their exposure to direct sunlight.
Be cautious though—midday sun can be intense, especially in the greenhouse. If the temperature hits above 25°C (77°F), I open the greenhouse door to allow some airflow and cooler temperatures inside. At night, I always bring the trays back inside to prevent them from getting too cold.
Transplanting and Spacing in the Garden
After the last frost of the season has passed, I’m ready to transplant my seedlings into the garden. Strawflowers like full sun and well-drained soil, so I make sure I choose a sunny spot in the garden and add plenty of organic matter to enrich the soil. Proper spacing is important to give each plant room to grow and branch out. I typically space them about 12 to 18 inches apart to allow them plenty of airflow and room to mature.
Watering Practices for Outdoor Strawflowers
Once the strawflowers are settled into the garden, I make sure they get consistent water but avoid over-watering. These plants don’t like to sit in wet soil, so I water them deeply but allow the soil to dry out between waterings. I use a soaker hose or drip irrigation to keep the moisture at the roots without wetting the foliage. If we have a dry spell, I make sure to check them regularly, as strawflowers can wilt quickly if they dry out too much.
Pinching for More Blooms
To encourage more branching and a fuller, bushier plant, I pinch the main stem of the seedlings once they’re about 4 to 6 inches tall. This helps the plant focus on producing multiple flower stems rather than just one main stalk, and you’ll end up with a much more abundant crop.
Harvesting Strawflowers for Dried Bouquets
Now comes the fun part—harvesting! The trick with strawflowers is to harvest them before the buds are fully open. This is crucial because strawflowers will continue to open during the drying process. By cutting them just before they open, you ensure that the flowers hold their shape and color when dried.
To harvest, simply cut the stems with sharp scissors or pruning shears, and remove all the foliage. I prefer to hang them upside down in a cool, dark place with plenty of airflow. I use a fan to keep the air circulating, which helps discourage mold growth. If you don’t have a dedicated drying space, a well-ventilated shed or even a basement can work as long as it’s dark and dry.
Other Tips for Growing Strawflowers
Strawflowers are an excellent cut flower for drying, and once they’re harvested, they keep their color beautifully throughout the colder months. A few other tips for growing them include:
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Landscape fabric or mulch can be a great addition around your transplants to suppress weeds and help retain moisture during hot, dry summers.
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Regularly check for pests, as strawflowers can attract aphids or spider mites if conditions are too humid or stagnant.
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Strawflowers are fairly drought-tolerant once established, but they still need regular watering when they’re young or during extreme heat spells.
Growing strawflowers has been a rewarding experience on my dried flower farm in Port Perry. With their gorgeous colour, long-lasting blooms, and versatility in both fresh and dried arrangements, they’re truly a staple in my farm’s flower lineup. Whether you're just starting out or looking to expand your dried flower garden, I hope this guide helps you grow a beautiful crop of strawflowers this season!
Happy farming,
Sarah
