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Planting sunflowers is an easy way to add some brightly-colored cheer to your summer garden. Here is a quick guide on how to properly plant and grow these classic flowers.
Planting sunflowers starts with finding the right seeds to plant. Fortunately, there are many different types of sunflowers to suit every different space. Here are some wonderful types of sunflowers to plant:
All of these different sunflowers are easy to plant and take care of in your garden.
Plant your sunflower seeds in a sunny location where the leaves of the plant will be in direct sunlight for at least 6 hours per day. Sunflower plants will grow in lower-light areas, but they need ample sunlight to grow tall and flower at their best.
Sunflower plants grow best in well-drained sandy loam soil. That said, these hardy seeds can germinate and sprout in less-than-ideal soil with surprising enthusiasm. Wherever you plant them, be sure to figure out how you’ll water the sunflower plants, especially while they are small. While sunflowers sometimes sprout up entirely on their own, they grow best with a bit of added water when the soil dries out.
Plant sunflower seeds outdoors in the ground when the danger of hard frost has passed, usually around the month of May in many temperate climates. As a rule of thumb, many gardeners wait a week or two after the average last frost date in their local area before planting sunflowers.
While sunflower sprouts are somewhat hardy, they do best when germinated in warm, moist soil (at least 70°F/21°C). Areas that rarely see freezing temperatures may be able to plant sunflowers in March or April, while those in the coldest northern zones may wish to plant sunflowers in mid-May or early June.
If you’ve missed the spring planting window for sunflowers, it is entirely possible to plant sunflowers in the early summer and still enjoy flowers later on in the summer. Many florists plant new sunflower seeds every week or two throughout the spring and early summer to ensure an ongoing harvest in late summer and early fall.
For instance, the popular Sunrich Sunflowers (5′ tall) each grow their flower only 60-70 days after sowing them outdoors. If a packet of these seeds were planted in early July, they may well bloom in early September if the weather remains moderate.
Planting sunflowers is easy once you have the seeds and a spot to plant them.
Use a trowel to dig a small hole, no deeper than about 1″ deep. Place the sunflower seed in the hole and replace the dirt on top of it. Then water the soil area, watching to make sure that the water seeps into the soil instead of running off away from the buried seed.
Sunflower seeds planted in a nice light potting mix or garden compost may not require any digging. The seeds can often be pushed right down into the soil to a depth of 1/2″ to 1″ deep. Easy peasy!
If you have a bit of extra time, try soaking the sunflower seeds for 4-6 hours prior to planting them. This will help ensure that the dormant seed has access to water, which is a very important sign for the seed to “wake up” and sprout. Give your soaked sunflower seeds a rinse and then plant them in the same manner as un-soaked seeds (including watering the area after planting).
Keep the sunflower seeds and the surrounding soil well-watered as the sprouts emerge and begin to take hold. Once the thin stalk has developed several sets of leaves, the plant will be more hardy and tolerant to dry soil. That said, even sunflowers do need moisture to grow, as it fills each plant cell and helps the plant grow its tall, stately stem. Water your sunflowers once a week in most conditions (more in a very dry climate, and less in a moist location). Check the sunflower plants often to look for signs of drooping or crisped leaves from dehydration or moisture-related issues like fungus.
Sunflowers can grow very well in containers and planter pots given the right potting soil and the right variety of sunflowers. Choose a large, well-draining pot for your sunflower plant, and plant only one sunflower in each pot. Also opt for a lightweight, well-drained organic potting mix.
While you could grow any type of sunflower in a large enough pot, there are some small varieties that do particularly well in containers. Here are two of the best sunflower varieties for growing in pots:
Most types of sunflowers take about 3 months to grow. Some sunflowers can take as little as 65 days to flower (just over 2 months), while others may take as many as 100+ days (over 3 months) to grow their classic cheerful blooms. Once the flowers appear and pollination begins, it will take another few weeks for the sunflower seeds to start forming and developing inside the flower heads.
In general, the shorter varieties with smaller flowers grow large enough to bloom more quickly than the tall sunflowers with giant flower heads. For instance, the tiny Suntastic Dwarf Container Sunflower can start blooming in 65 days, while the Mammoth Sunflower can take 90 days for its single flower to bloom (and up to 120 days for the sunflower seeds to develop).