Buzz
Sunflowers are native to the Americas. Sunflower oil is used to make biodiesel or cooking oil, and sunflower seeds make a tasty snack. A sunflower bloom also adds a cheerful touch to brighten up any window or balcony. Growing sunflowers in a pot is a simple and enjoyable activity that even children can do.
Steps
Choose sunflower seeds and a plant pot
Buy sunflower seeds. You can purchase sunflower seeds at nurseries, garden centers, or order them online. If you're looking for rare sunflower varieties, online ordering might be easier.
- Sunflower seeds are also available at supermarkets or convenience stores, but these are for eating, not planting. Once roasted, sunflower seeds won't germinate.
- If you already have a fully-grown sunflower plant, you can store sunflower seeds in an airtight container in the fridge. Try to sow the seeds as early as possible, as older seeds might have a lower germination rate.
- It's best to choose dwarf sunflower varieties, as larger varieties only thrive when planted in the ground.
Choose sunflower varieties. A packet of sunflower seeds (or a list on the website) will indicate the variety and type of sunflower, as well as the maximum height the plant can reach. If purchasing seeds at a nursery or garden center, you can ask the staff for help in selecting the right one.
- Single-stem sunflowers will produce one flower per seed. If you want flowers all summer long, you will need to replant every 10-14 days. On the bright side, these varieties produce less pollen, so there will be less pollen on your porch, furniture, and clothing.
- Branching sunflowers will produce multiple flowers throughout the season, and there’s no need to replant. These sunflowers also come in unique colors such as wine red and chocolate.
Choose an appropriate plant pot. Select the pot size according to the height of the variety and the number of plants you want to grow in each pot. In general, most dwarf sunflower varieties can be grown in pots around 30-40 cm in size.
- The Mammoth sunflower variety requires a pot with a minimum capacity of 20 liters.
- If reusing a container previously used for another purpose, remember to clean and sterilize it. You might need to drill drainage holes in the bottom, as seeds can rot if the pot doesn’t have proper drainage.
- Don’t forget to place a tray underneath the pot to catch any excess water that drains out.
Fill the pot with planting soil and organic compost. Choose a nutrient-rich topsoil or a type of soil specifically designed for sunflowers. Organic compost will also provide nutrients for the plants.
- Good quality topsoil will have a pH level between 5.5 and 7.5 and contain over 3% organic matter. These numbers should be listed on the packaging.
- If you’re using high-quality topsoil, there’s no need to add drainage materials like sand or gravel at the bottom of the pot, as this could actually block water flow and make drainage less effective.
Plant the sunflowers
Press each seed into the soil about 2.5 cm deep. If planting multiple seeds in a pot, space them 10-13 cm apart. You can add a thin layer of compost on top of the soil after planting the seeds.
- Make sure to leave a gap of 10-13 cm around each seed. Avoid planting the seeds too close to the edge of the pot.
Water the seeds daily. Sunflowers require more water than most other plants during their growth phase. Ensure that the soil remains moist and drains well. Water the plants with at least 8 liters of water per week while the seeds are germinating.
- Sunflowers that aren’t watered enough during their early stages will develop thin, weak stems that won’t be able to support the heavy flowers standing upright.
- Soil has good drainage if water passes through relatively quickly. Standing water or water pooling in the pot is a sign that the pot has drainage issues.
Monitor the seed germination. Within 1 to 10 days, the sunflower seeds will begin to germinate and sprout into seedlings. During this time, continue watering the seeds daily and ensure that the soil stays moist, particularly around the seeds.
- If planting sunflowers outdoors, you can cover the seedlings with a basket or use netting to protect them from birds.
Care for sunflowers
Fertilize the plants if desired. While sunflowers don’t necessarily require fertilizer for growth, it can enhance the color and vibrancy of the flowers. Start with a high-nitrogen liquid fertilizer, then switch to one with higher phosphorus content once the plant starts to bud.
- You can also mix diluted fertilizer with the watering water. Be careful not to over-fertilize, as the stems may become too weak and break.
Place sunflowers in direct sunlight. As the seedlings grow, they will need as much sunlight as possible for the stems to become sturdy enough to support the large flowers. When fully grown, sunflowers require 6-8 hours of direct sunlight each day.
- Sunflowers track the sun’s movement. If they’re not placed in direct sunlight, they’ll lean toward the sun and damage their stems.
Tưới nước cho cây mỗi tuần vài lần. Cây hướng dương cần được tưới thường xuyên hơn những loài cây khác. Bạn nên kiểm tra đất khoảng 1-2 ngày một lần – đất phải luôn luôn ẩm. Thông thường, bạn cần tưới cho cây hướng dương 8 lít nước mỗi tuần.
- Cây hướng dương trồng ngoài trời khi cao đến 30-60 cm có thể chỉ cần nước mưa là đủ, nhưng bạn có thể phải tưới thêm vào những ngày khô nóng.
- Khi cây ra hoa, bạn hãy tưới xung quanh rễ cây trong phạm vi 8-10 cm.
- Để sẵn bình xịt để phun cho hoa thường xuyên.
Cắm cọc chống cho cây nếu cần thiết. Một số giống hướng dương lùn có thể không mọc cao đến mức cần có cọc chống, nhưng nếu cây đạt đến độ cao 90 cm trở lên, có thể chúng cần dựa vào vật nào đó để giữ cho những bông hoa không bị rũ xuống.
- Đừng cắm cọc chống ngay bên trong chậu trồng cây. Khi cây cao hết cỡ, nó có thể làm lật chậu. Bạn nên buộc cọc vào tường, ống thoát nước hoặc một vật nào đó.
Thu hoạch hạt hướng dương. Nếu giống hướng dương bạn đang trồng có hạt ăn được, hãy để cho hoa tàn trên cây. Hạt hướng dương sẽ chín và khô đi. Nếu trồng hướng dương ngoài trời, bạn nên dùng túi giấy hoặc lưới che chắn để chim khỏi ăn hết hạt.
- Thông thường, hạt hướng dương có màu đen hoặc xám với các sọc trắng là hạt ăn được.
- Nếu mặt sau bông hoa chuyển màu nâu thì thường là hạt đã có thể thu hoạch được.
- Khi hạt hướng dương đã khô, bạn có thể trữ trong hộp đậy kín ở nhiệt độ phòng đến 4 tháng. Bạn cũng có thể đông lạnh hạt nếu cần bảo quản lâu hơn.
- Nụ hoa hướng dương cũng ăn được. Chần lên trước để khử vị đắng, sau đó đem hấp hoặc luộc trong 3 phút. Nụ hoa nhúng trong bơ tỏi ăn cũng ngon.
Lời khuyên
- Có nhiều tổ chức phi lợi nhuận như Seed Savers Exchange (www.seedsavers.org) bán các giống hương dương quý hiếm.
- Mặc dù hầu hết mọi người thích ăn hạt hướng dương rang, nhưng bạn cũng có thể ăn hạt còn sống. Hạt hướng dương dồi dào vitamin nhóm B và vitamin E, ngoài ra còn là nguồn cung cấp protein.
Warnings
- Sunflowers don’t like being transplanted, so it’s best to choose a large enough pot for them to reach their full size.
- Not all sunflower varieties produce edible seeds. If you intend to harvest the seeds for snacking, make sure the variety you’re planting is suitable for consumption.
