You may have driven past a field of sunflowers and wondered why people grow them. Well, they are a very marketable crop. And, believe you me, there’s no secret technique to growing sunflowers. All it really takes is sowing a seed. The sunflower buds then follows the sun as it treks across the sky each day until it blooms. Apart from growing a cheerful flower, there are also other benefits to growing sunflowers.
Why you should consider growing sunflowers
- The sunflower is an ideal multipurpose plant. The flower head has hundreds of tiny inflorescences grouped together into what appears to be a single flower head. Each of these tiny flowers is loaded with the nectar and pollen that attract and feed a huge variety of pollinators and beneficial insects.
- The sunflower seeds are processed into meal and oil extracted from them. They are also used as bird feed.
- Stems are not only the backbone of the sunflower, they make nice materials on large and small scales like paper. Industrial agriculture can also upcycle the stems and add them as a component of thermal insulation, along with other plant byproducts.
- The plant’s leaves hold medicinal qualities. They are used to treat cuts, lung infections and reduce fevers. They are also great feed for cattle.
- The roots of sunflowers are delicious raw or cooked. Furthermore, they support the intestinal ecosystem by providing inulin. The plant has the ability to remove harmful toxins from your soil including lead, arsenic, zinc, chromium, copper and manganese.
You can plant sunflower seeds directly into the soil. To plant in rows, space the seeds about 15 cm apart in a shallow trench between 2.5 and 5 cm deep. In sandy soil, 5cm deep is better. Cover and water until the seeds sprout in 7 to 10 days. When first true leaves appear (the second set of leaves); thin plants to about 60 cm apart. Depending on the variety, sunflowers will mature and develop seeds in 80 to 120 days.
For maximum seed production space rows 60 to 120 cm apart. Use traditional, tall, seed-producing varieties such as ‘Mammoth’ or ‘Paul Bunyan Hybrid’, ‘Aztec Gold Hybrid’, or ‘Super Snack Hybrid’.
To grow smaller flowers for bouquets, space plants much closer together? about 5cm apart in. Skip fertilizing. The plants will be much smaller, with fewer branches, but the stems will be longer and flower heads a good size for arrangements.
1. Sunflower roots spread widely and can withstand some drought
However, you have to water them regularly when they are about 20 days before and after flowering. This is their most important growth period. Deep, regular watering helps encourage root growth, which is especially helpful with taller sunflower varieties bearing top-heavy blooms.
2. Sunflowers do not need fertilizing
However, because they grow vigorously (they can easily grow 2 metres in just 3 months), it’s a good idea to add some slow-acting granular fertilizer to poor, thin soil. The better their diet, the larger the flowers will grow. It’s important not to overdo the nitrogen because that can delay flowering. Spreading a 2- or 3-inch mulch layer of some kind of organic material on the soil can also help reduce moisture loss through evaporation and discourage weeds.
3. Some sunflower varieties don’t need any staking
However, you have to support plants that are multi-branched or grow over 1m tall. Their branches can be fairly brittle, especially at the points where they join the stems. The plants are vulnerable to summer winds and rain especially if they are shallow rooted with many heads. Tie the plants loosely to stakes cloth or other soft material.
4. Birds can be a problem when seeds ripen and harvest time approaches
To keep birds away, barrier devices are the most effective. So, as the heads mature and flowers face down, cover each one with white polyspun garden fleece. It will let light and air in and keep critters out. Furthermore, try cutting away some of the leaves that are closest to the heads so birds don’t have anywhere to perch.
Sunflowers can be infected with fungal diseases such as mildews and rusts. Downy Mildew causes mottling and pale areas on upper leaf surfaces and a fuzzy mold growth on their undersides. Eventually the leaves wither and die. The oldest leaves are usually infected first. Downy mildew is most likely to occur on cool damp nights and warm humid days. It spreads by means of tiny spores carried to plants and soil by wind and rain or transmitted by garden tools. It will not kill a mature plant; it just mars its appearance.
Rust appears on upper leaf surfaces first as yellow or white spots that turn brown or black. Puffy blisters then appear on the undersides. The disease may spread to stems and flowers causing distorted growth. Rust sometimes spreads to the cultivated sunflowers from weeds such as wild mustard, shepherd’s-purse, pigweed, and lamb’s-quarters.
If fungal diseases are spotted early, spraying with a general garden fungicide as directed on the product label can protect healthy foliage. Remove and destroy seriously infected plants. Keep the area weeded and clean up plant debris from the garden in the fall. Disinfect tools by dipping them in a solution of 1 part household bleach to 4 parts water. Keep your hands clean, and do not handle plants when they are wet.
A small gray sunflower moth sometimes lays its eggs in developing sunflower blossoms. Its larvae are greenish-yellow with 5 brown stripes down their backs. They feed in the flower and destroy seeds, creating a mass of webbing and debris. Pick the worms from the plants and mash them between your fingers or drop them into a plastic bag for the trash. If lots of plants are infested, spray or dust the flowers with a product containing Bacillus thuringiensis (Bt) as soon as you see the larvae. The larvae will eat the bacterium and soon die. Because sunlight and rain rapidly inactivates Bt, respray as directed on the product label.
Are your plants ready for harvest?
When your plants are ready for harvest, the reverse side of the flower heads turns from green to a yellow-brown. Large heads will nod downward. A close look will reveal the tiny petals covering the developing seeds have dried and now fall out easily exposing the tightly packed mature seeds.
To harvest the seeds, cut off the seed heads with 20cm or so of stem attached and hang them in a warm, dry place that is well-ventilated and protected from rodents and bugs. Keep the harvested seed heads out of humidity to prevent spoilage from molds and let them cure for several weeks. When the seeds are thoroughly dried dislodge them by rubbing two heads together, or by brushing them with your fingers or a stiff brush. Allow the seeds to dry for a few more days then store in airtight glass jars in the refrigerator to retain flavor.
References: Food Source Information