Growing sunflowers in Washington is an incredibly rewarding experience. The state’s mild climate and ample sunshine make it an ideal spot for growing vibrant and cheerful flowers. Sunflowers are easy to grow and require minimal care, making them a perfect choice for novice gardeners.
With a bit of planning and a few simple steps, you can create a stunning display of sunflowers in your own backyard. Sunflowers bring beauty, color, and joy to any garden, and with Washington’s mild climate, they are sure to thrive.
Washington climate and growing zones
Growing Zone 4a, located in the northernmost parts of the state, has an average annual minimum temperature of -30 to -20°F. This zone is suitable for cold-tolerant plants such as quince, pear, and apple trees, as well as blueberry and raspberry bushes.
Growing Zone 5a has an average annual minimum temperature of -20 to -10°F. This zone is suitable for cold-tolerant plants such as rhododendrons, hardy roses, and hydrangeas.
Growing Zone 6a has an average annual minimum temperature of -10 to 0°F. This zone is suitable for a wide range of plants, including lilacs, azaleas, and magnolias.
Hardiness Zones 7a Through 9a
Growing Zone 7a has an average annual minimum temperature of 0 to 10°F. This zone is suitable for a wide variety of plants, including many varieties of flowers, shrubs, and trees, such as dogwood, hickory, and maple.
Growing Zone 8a has an average annual minimum temperature of 10 to 20°F. This zone is suitable for a wide variety of plants, including many varieties of flowers, shrubs, and trees, such as oak, sycamore, and cherry.
Growing Zone 9a has an average annual minimum temperature of 20 to 30°F. This zone is suitable for a wide variety of plants, including many varieties of flowers, shrubs, and trees, such as willow, maple, and beech.
Growing sunflowers in Washington
Growing sunflowers in Washington is possible but can be a bit tricky. Washington has a climate that is suited for a variety of crops, but sunflowers can be a bit more challenging due to the cooler temperatures. The cold winter months can make it difficult for sunflowers to survive, especially if the soil is not adequately insulated from the cold.
In areas with colder climates, sunflowers should be planted in late spring or early summer, so that they can have time to get established before the cold weather arrives. Planting sunflowers in a location that is sheltered from the wind and that is exposed to direct sunlight can help to keep the plants warm. Mulch around the plants can also help to insulate the soil, keeping it warmer.
In areas with warm climates, sunflowers can be planted year-round. They will do best in full sun and will require regular watering. Adding compost or fertilizer to the soil can also help to provide the plants with the nutrients they need.
Some of my favorite varieties of sunflower include:
- Mammoth Grey Stripe Sunflower (Helianthus annuus) – 75-100 days to maturity
- Teddy Bear Sunflower (Helianthus annuus) – 60-90 days to maturity
- Red Sun (Helianthus annuus) – 65-95 days to maturity
- Autumn Beauty Sunflower (Helianthus annuus) – 75-90 days to maturity
- Lemon Queen Sunflower (Helianthus annuus) – 75-95 days to maturity
- Velvet Queen Sunflower (Helianthus annuus) – 90-110 days to maturity
- Dwarf Sunspot Sunflower (Helianthus annuus) – 60-90 days to maturity
- Giant Sungold Sunflower (Helianthus annuus) – 85-110 days to maturity
- Evening Sun Sunflower (Helianthus annuus) – 75-95 days to maturity
- Sundance Kid Sunflower (Helianthus annuus) – 75-95 days to maturity
When to start sunflowers indoors in Washington
Sunflower seeds should be started indoors 4 weeks before your final frost date. In Washington, the final frost dates are:
- Zone 4: Around May 12th
- Zone 5: Around April 30th
- Zone 6: Around April 21
- zone 7: Around April 3
- zone 8: Around March 28th
- zone 9: Around February 28th
You should also consider the size of the variety of sunflower you are planting, as shorter varieties can be planted later and taller varieties will need to be started a week or two earlier. Sunflowers should be started indoors:
- Zone 4: Around April 14th
- Zone 5: Around April 1st
- Zone 6: Around March 24th
- zone 7: Around March 6th
- zone 8: Around February 27th
- zone 9: Around January 31st
Starting sunflowers from seed is a relatively easy process that can be done both indoors and outdoors. To begin, you will need to purchase sunflower seeds from a garden center or online. When selecting seeds, make sure to look for the desired variety you want to grow. Once you have your seeds, you can choose to start them indoors 4 weeks before the last frost date for your region.
Fill a seed tray with starter soil and moisten it with a spray bottle. Place your seeds on top of the soil, cover them lightly with starter soil, and water them gently. Place the tray in a warm and sunny spot, and keep the soil moist. Once your plants have grown 2-3 sets of leaves, you can transplant them outdoors.
Planting sunflowers outside in Washington
Sunflower seeds should be planted outdoors after the last average frost date for your area. Planting sunflower seeds too early can result in poor germination and seedling growth and potentially death if there’s a hard freeze.
When planting outdoors, make sure the area has plenty of sunshine and well-draining soil. Dig a hole that is twice the size of the root ball, and fill the hole with compost or aged manure. Place the seedling in the hole and backfill with soil, then water deeply.
For the remainder of the sunflower’s life, make sure to keep the soil moist and fertilize regularly. With proper care, you should have beautiful sunflowers in no time!
When to harvest sunflower seeds in Washington
When sunflower seeds are ready to be harvested, the back of the flower head will be dry and start to turn brown. The individual seeds will be dry and firm. The green husks surrounding the seeds will have turned yellow or white and begun to dry out. To check if the seeds are ready to be harvested, lightly pinch the seed head between your thumb and forefinger. If the husks break open easily, the seeds are ready to harvest.
Harvesting sunflower seeds is easy. Cut the flower head off the stem and spread it out on a clean surface. To remove the seeds, use your hands to rub the flower head and release the seeds. Collect the seeds in a large bowl or container. Once the seeds are harvested, store them in an airtight container in a cool, dry place. Make sure the container is well sealed to keep the seeds from going bad. Sunflower seeds can last for up to a year if stored properly.
Sunflower seeds are delicious and nutritious snack food. They can be eaten raw, toasted, or sprouted. Sunflower seeds are also used in salads, cereals, granola, and energy bars. They are loaded with essential vitamins and minerals like Vitamin E, phosphorus, magnesium, and zinc. Sunflower seeds can also be used to make sunflower seed butter, which is a great alternative to peanut butter.
In addition to being a healthy snack, sunflower seeds are also used to make birdseed. You can leave your sunflowers intact outside well after the flowers have died to give your local birds a tasty snack!