These hardy, easy-to-grow annual flowers brighten up any garden with their large, theatrical corolla. Sunflowers can grow from 60cm up to 4.5m tall, depending on the variety, and their seeds can make for a tasty snack. Follow these instructions to learn how to plant, grow and harvest their seeds.
Steps
Part 1 of 3: Preparing the Garden
Step 1. Choose the sunflower variety that best suits your garden
Some can grow several meters, while there are "mignon" versions that do not grow more than 90 cm. Here are some types, large and small:
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Mammoth Sunflower:
Despite the name they have not become extinct! You can grow giant sunflowers if you choose this variety.
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Common Sunflower:
this variety produces large flowers that grow up to 15cm in diameter. The petals can become mahogany-bronzed in color and the maximum height of the flower can reach 2 meters.
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Sunbeam:
it is a medium-sized variety, the height of which reaches 1.5 m with flowers about 7.5 cm in diameter. The petals are long and asymmetrical. The center of the corolla is yellow and gives a great scenic effect to each bouquet.
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Dwarf sunflowers:
they are small sunflowers that reach 90 cm in height; this is the perfect strain if you don't have a lot of space in the garden.
Step 2. Identify an area of the garden in full sun
Sunflowers grow in warm climates and need to be exposed to the sun throughout the day. Regions where summers are long and hot are perfect habitats.
Find a spot protected from the wind. If possible, it is best not to expose sunflowers to gusts of wind. Plant the seeds along the edge of a fence, on one side of the house, or behind a row of sturdy trees. It would also be advisable to plant them on the north side of the garden. This will prevent them from overshadowing other plants
Step 3. Check the pH of the soil
Sunflowers are acidophilic and prefer a soil with a pH between 6 and 7.5. However, they are relatively hardy flowers and adapt to almost any soil type.
- Ask your municipality's agriculture office if it has a pH test kit with attached instructions. After adding products to regulate the acidity of the soil, repeat the test.
- If the pH is below 6, enrich the soil with acidic compost.
- If the pH is above 7, 5 add some granular sulfur to lower it.
Step 4. Make sure the soil is well draining
Although sunflowers are sturdy, muddy ground damages them.
- If the soil isn't well drained, build a planter that is.
- If necessary, build a raised planter. Use 2.4m long cedar planks. Cedar is used because it does not rot when exposed to water.
Step 5. Wait for the soil to warm up before planting
Sow in early summer, when the soil has a higher temperature. Usually it takes place between mid-April and the end of May.
Part 2 of 3: Sow the Sunflowers
Step 1. Loosen the soil with your hands or a shovel
The soil must be soft and light to accommodate the sunflower seeds. If it's low in nutrients or doesn't drain well, add 7-10cm of compost.
Step 2. Drill holes about 2.5 cm deep and spaced 45 cm apart, depending on the variety of sunflowers you have chosen
You can use your hands to make these holes. If you decide to plant rows, be sure to spacing them at least 70cm apart.
- If you have chosen a variety of very large sunflowers, space the seeds 45 cm apart.
- If you have chosen a medium-sized variety, space the seeds 30 cm apart.
Step 3. Place a couple of seeds in each hole and cover them with soil
You can differentiate the sowing of several weeks, in order to have different blooms throughout the summer. Since sunflowers are annual plants, they bloom only once a year. By planting the seeds at different times you can enjoy their magnificent corollas for a longer period of time.
Step 4. After planting, lay out a thin layer of fertilizer
Choose an organic fertilizer if possible and sprinkle it over the planting area to aid growth.
Step 5. Water thoroughly after sowing and fertilizing
Make sure the soil is moist but do not submerge or drown the seeds.
Part 3 of 3: Caring for Sunflowers
Step 1. Wet the plants carefully every day
Sunflowers have deep roots and infrequent but abundant watering is preferable to infrequent and frequent watering. Adjust the watering rhythm according to the climate and temperature. Sunflowers should bloom in mid to late summer, approximately 2-3 months after planting.
Step 2. Mulch the area
Once the plants are tall enough to be able to apply mulch without breaking them, cover the soil with a layer of straw or another type of mulch to retain moisture and prevent weeds from growing. Renew the layer after heavy rains.
If you are growing sunflowers to collect their seeds or for a floral display, apply 4 cm of fully mature fertilizer or compost when the plants have reached 50 cm in height
Step 3. Scoop if needed
If you live in a region with a lot of wind or find that the flowers are not very strong, consider supporting the sunflowers with bamboo sticks.
Step 4. Eliminate any pests and molds
While not particularly insect susceptible flowers, the gray moth can lay eggs right in the flower. Manually eliminate worms.
- Sunflowers can be attacked by parasitic fungi, such as "rust". If this happens, spray them with a fungicide product.
- Deer and birds love sunflowers. Install a safety net to prevent these animals from destroying your garden.
Step 5. Cut the flowers to make a decorative bouquet
If you want to put sunflowers in a vase, cut the stem diagonally early in the morning, before the flower opens fully. Change the water in the vase every day to keep the flowers fresh.
Step 6. Collect the seeds
When they start to dry out, turn brown and the flower heads start to fall off, it's time to collect the seeds. Cut the stem about 5 cm below the flower head and hang it upside down until completely dry. For this, choose a dry and well-ventilated room.
If you want to get some delicious roasted seeds, soak them overnight in salted water. The next day, drain them and arrange them on a baking sheet. Roast the seeds in a warm oven (90 ° C-120 ° C) until golden brown
Advice
- Although a well-watered soil with plenty of peat, compost or compost will help them grow tall and strong, sunflowers do well in any type of soil.
- Remember that they grow very tall and can cast shade on other plants. Keep in mind that they always pop up in the direction the sun rises (east).
- Eliminate weeds around sunflowers, do not plant grass and avoid using chemicals.
- It is a good idea to leave the sunflowers where you will plant them; if you try to move them they won't grow as well.
- It's best to plant a few sunflowers if you don't have a lot of space, because the more they have to compete for low nutrients, the less strong they become.
- If your garden is visited by seed-eating birds, protect the sunflowers with a polyester garden net.
Warnings
- Fallow deer love sunflowers. If there are fallow deer in the area where you live, protect the seeds.
- Sunflowers do not like the cold. Protect them from frosts and wait for it to get warmer before planting them.
- Birds can eat the seeds immediately after sowing them. Put a safety net over the area to prevent them from doing so.
