My Favorite Cosmos, Dahlias, Nasturtium, and Zinnias to Grow from Seed in Zone 6 (and Zone 7) in My Oklahoma Cut Flower Beds
Oklahoma isn’t always kind to gardeners. The heat arrives early, the wind never stops, and the soil can feel like it’s testing your resolve. Or, like this year, the rain never stops. But even here—in the unpredictability of Zones 6 and 7—there are a few cut flowers that show up with joy and abundance, year after year. These are the tried-and-true cut flowers I sow from seed every season. They’re beautiful, reliable, and, with a little care, generous with blooms from late spring through early fall.
Whether you’re just beginning to dabble in cut flowers or planning a full potager with baskets of blooms, start with these:
Cosmos
Varieties I love: ‘Cupcake Blush’, ‘Apricotta’, ‘Double Click Rose Bonbon’
Cosmos thrive on neglect—in the best way. Sow them directly after your last frost, and they’ll reward you with tall, airy stems and delicate blooms that practically arrange themselves. I lean toward soft pinks and whites for the most romantic, high-yield cuts, and I let them reseed for a more effortless return.
- Tip: Deadhead regularly or cut for the vase and they’ll bloom nonstop.
- Bonus: Pollinators love them.
Dahlias (from seed)
Varieties I love: ‘Creme de Cassis’, ‘Cafe au Lait Rosé’, and seed-grown specialty mixes
While many gardeners start with tubers, I’ve found that starting certain dahlias from seed offers stunning results with less upfront cost. You’ll get more variation, yes—but often, that’s where the magic is. Seed-grown dahlias tend to produce slightly smaller blooms, but they’re prolific and perfect for arrangements.
- Tip: I like to nestle dahlias in the cosmos.
- Favorite suppliers: I’ve been impressed with some of the suppliers I’ve found on Etsy.
Nasturtiums
Varieties I love: ‘Purple Emperor, ‘Ladybird Rose’, ‘Orchid Cream’
Don’t underestimate the humble nasturtium. It’s edible, arresting, and beautifully unpredictable. In Oklahoma’s climate, I sow nasturtiums in early spring and again in late summer for a fall flush. The leaves are lush, the blooms are punchy, and they add a wild, painterly texture to bouquets.
- Tip: Plant in partial shade during the height of summer—they’ll dry out quickly in too much heat.
- Kitchen tip: Use the blooms as a salad topping.
Zinnias
Varieties I love: ‘Queen Lime Blush’, ‘Oklahoma Salmon’, ‘ZInderella Lilac’
Zinnias are the backbone of my summer garden. They stand up to heat, drought, and neglect, and they come in a range of soft, muddy tones that elevate any bouquet. I avoid the overly neon types and opt for vintage shades that feel elegant and curated.
- Tip: Pinch young plants early to encourage bushier growth.
- Arrangement idea: Mix with herbs like basil or mint for a fuller bouquet.
Final Tip
Plant seeds in early spring for summer flush. And plant in July or early August for blooms to last you well into October and even November.
These flowers are easy not because they require nothing—but because they give so much in return for so little. I plant them year after year, not just because they’re beautiful, but because they thrive here—in our red clay, under our big skies.
Whether you’re arranging bouquets for your kitchen table, gifting to neighbors, or dreaming of starting a flower stand, these are the seeds that can get you there.
Want to shop my favorite cut flower seeds?
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