Sunflowers make great cut flowers, and can be planted every couple of weeks from the time the soil warms up through late summer. Harvest sunflowers for bouquets when petal color just begins to show, or as flowers are about to open. Johnny’s Selected Seeds offers a sunflower comparison chart with photos to help gardeners or commercial growers determine which varieties will work best for their purpose.
If you prefer not to have pollen dropping onto tables, grow the pollenless varieties, which are hybridized to produce no pollen and last longer in a vase. They’re still attractive to pollinators. Sunflower Selections breeds hybrid sunflowers and offers seed from their Woodland, California location. Most of their sunflower varieties are pollen free, which means they cannot pollinate themselves. They can be pollinated by bees and other insects that carry pollen from other sunflowers, which results in seeds that, if planted, will not look like the original hybrid variety you planted.
One of the absolute easiest flowers to grow from seed is Cosmos, which Barlow says will last three days in a vase—not overly long—but a welcome bouquet flower, and so easy to grow. Cosmos are native to Mexico and thrive on warm weather. Two species are responsible for most of the Cosmos we know and grow. Cosmos bipinnatus is the one breeders have fiddled with the most, creating a respectable variety of petal shapes and colors. The species sulphureus is more compact and has flowers that reside in the yellow and red range.
Another Cosmos has entered the fray, and it has something completely different to offer. Cosmos atrosanguineus, or chocolate cosmos, has flowers that are scented like chocolate. I had the pleasure of finding this plant with my nose in a sunny public garden. Its flowers, a dark red, were appropriately growing at nose height. According to Winterrowd, chocolate Cosmos is tuberous-rooted like a Dahlia, and can be overwintered in a cool but frost-free location.
Cut flowers are catching on in a big way. Barlow says, “Our top-selling cut flower varieties are ’Spring Sunshine’ sweet peas, celosia ‘Cramer’s Burgundy’, zinnia ‘Queen Red Lime’ and ‘Cupcakes’, sweet scabious ‘Black Knight’, Cosmos ‘Xanthous’, sunflower ‘Mexican Torch’, Zinnia ‘Benary’s Giant Mix’ cornflower ‘Emperor William’, sunflower ‘Pan’, and larkspur ‘Misty Lavender’”.