Sunflowers are heavy feeders, however, so the soil needs to be nutrient-rich with organic matter or composted (aged) manure. Sunflowers thrive in slightly acidic to somewhat alkaline soil (pH 6.0 to 7.5). They have long tap roots that need to stretch out in preparing a bed, dig down 2 feet in depth and about 3 feet across.They’re not too fussy when it comes to soil pH either. The planting spot shouldn’t pool with water after it rains. Otherwise, sunflowers aren’t too picky about soil, but for the best results, it shouldn’t be too compacted. –Robert Kelley Weeks (1840–76) How Long Do Sunflowers Take to Bloom?Ī fairly fast-growing flower for their size, most sunflower varieties mature in only 80 to 95 days. The largest sunflower varieties grow to over 16 feet in height, while smaller varieties have been developed for small spaces and containers and rarely grow larger than a foot tall! The flower heads can reach over 12 inches in diameter within the large seeded varieties.įirst and foremost, find a sunny spot! Sunflowers grow best in locations with direct sunlight (6 to 8 hours per day) they require long, warm summers to flower well.Ĭhoose a location with well-draining soil. Choose between those with branching stems or single stems, those that produce ample pollen for pollinators or are pollen-free (best for bouquets), those that stay small or tower above the rest of the garden, or those that produce edible seeds! Learn more about why you should start growing these happy flowers in your garden. There are tons of varieties of sunflowers available today, so there’s bound to be one that fits your garden. Heliotropism happens during the earlier stages before the flower grows heavy with seeds. Sunflowers are heliotropic, which means that they turn their flowers to follow the movement of the Sun across the sky east to west, and then returns at night to face the east, ready again for the morning sun. The flowers come in many colors (yellow, red, orange, maroon, brown), but they are commonly bright yellow with brown centers that ripen into heavy heads filled with seeds. Its scientific name comes from the Greek words helios (“sun”) and anthos (“flower”). The sunflower ( Helianthus annuus) is an annual plant with a large daisy-like flower face.

They make beautiful cut flowers and their seeds (and oil) are a source of food for birds and people! See our Sunflower Guide for information on everything from planting to growing to harvesting. With bright blooms that go all summer, sunflowers are heat-tolerant, resistant to pests, and attractive to pollinators and birds.

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