Known for their cheery ornamental addition to the garden, sunflowers actually have an amazing variety of uses. The sunflower seeds and seed meal can help feed people, birds, and animals; the sunflower oil is an important commodity used for cooking and in cosmetics.
Every spring homeowners all over grab packets of sunflower seeds to plant in their garden, and small kids bring home red plastic solo cups they've planted sunflower seeds in at school. With the following tips you can nurture those seeds into bold, beautiful, flowering giants in your backyard or garden.
1. Sow seeds directly into the soil
As quickly as sunflower seeds grow, plant them directly into the soil to avoid having leggy, tall seedlings that will need to be transplanted outside soon after germination. Sunflower seeds can be planted outside as soon as soil temps hit 55-60 degrees Fahrenheit.
2. Grow in full sun location
They are called sunflowers for a good reason! These plants are sun loving and do best when grow in garden locations that receive a minimum of 6-8 of direct, unfiltered light daily. Keep in mind their mature height and place at the edge of a sunny spot to prevent shading other, shorter plants.
3. Avoid potatoes and pole beans
The seeds, leaves, and stems of sunflower plants emit a substance that will inhibit the growth of other plants. This phenomenon is known as allelopathy (you can read more about it at Gardening Know How) and is a defense mechanism again plants that can be seen as threats. In the case of sunflowers it's best to keep them away from potatoes and pole beans.
4. Dig a moat around plants
Sunflowers are fairly drought tolerant and can withstand short dry spells. Dig a "moat" about 4" deep around the base of the plant extending out 18". Fill the depression with water once a week and allow the water to saturate the root zone.
5. Fertilize for good growth
Early in the growing season, fertilize your plants lightly with an all-purpose fertilizer to strengthen the stalk and encourage good growth. When the flowers bloom switch to a low-nitrogen fertilizer as nitrogen promotes vegetative growth.
6. Support tall stalks
Some varieties do not require any staking as the towering plants reach maturity. And some don't grow as tall as others so staking their heavy, seed-filled heads is never a concern. If you live in a windy area though, or are concerned about the stalks snapping under the weight of the flowers, faster supports around your sunflowers to keep them upright and healthy. If you're unsure about how to support them, do it yourself has a great step by step set of instructions.
7. Deter pests
Sunflower seeds are a tasty treat for many garden pests. When the flowers are full of seeds you will see a wide variety of animals trying to get a snack. If you plan on harvesting the seeds you will need to put up barriers to protect your plants. To keep deer away you can surround your sunflowers with a wire barrier (fencing, chicken wire, etc.); squirrels and birds can be deterred by covering the flower heads with white polyspun garden fleece.