Sunflowers, with their giant yellow blooms, are true eye-catchers in the garden, on the terrace, or even on the balcony. Here’s what matters most when it comes to sowing and planting sunflowers.
Sunflowers (Helianthus annuus) are popular for their cheerful, open-faced blossoms.
Growing sunflowers yourself – whether sowing or planting – is easy. You don’t even need a garden. If you choose compact varieties, sunflowers can be grown in pots on a balcony or terrace. However, choosing the right location, soil, and timing is essential for success.
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At a Glance: How to Sow and Plant Sunflowers
- The ideal location is sunny and protected from the wind.
- Soil should be loamy and nutrient-rich.
- The best time to sow is after the last frost, typically after the Ice Saints in May (mid-May).
- For direct sowing in the ground, plant seeds 2 to 5 cm deep and leave 10 to 40 cm between them depending on the variety.
- Water regularly and feed with liquid fertiliser or nettle manure to support growth.
- You can pre-cultivate indoors starting in March, and transplant seedlings outdoors from mid-May.
Sowing Sunflowers Directly Outdoors
You can sow sunflower seeds directly into your garden bed, but you should wait until there’s no risk of ground frost and the soil is consistently warm. In milder regions, this may be possible from April, but most home gardeners wait until after the Ice Saints in mid-May for safety.
- Choose a full sun and warm, sheltered spot.
- Use loamy, nutrient-rich garden soil, loosened and improved with a bit of sand for drainage.
How to sow:
- Plant seeds 2 to 5 cm deep in the soil.
- Leave 10 to 40 cm of spacing, depending on the variety (check the seed packet for guidance).
- Water thoroughly after sowing.
- Ensure consistent water and nutrient supply – sunflowers are heavy feeders.
- Use liquid fertiliser or nettle manure in watering.
- The cultivation period is 8 to 12 weeks.
How to Pre-Cultivate Indoors
If you want a head start, you can begin sowing in March or early April indoors.
- Use small pots (10–12 cm diameter).
- For small-seeded varieties, sow 2 to 3 seeds per pot.
- Seeds germinate at around 15°C (59°F) within 1–2 weeks.
- Once the seeds sprout, thin out the weaker seedlings, leaving only the strongest plant.
- Continue growing the seedling in a sunny location at a stable temperature.
Transplanting Seedlings Outdoors
You should wait until mid-May, after the risk of frost has passed, before transplanting your seedlings outdoors.
- Maintain a spacing of 20–30 cm between plants.
- Water generously, but avoid waterlogging.
- As a preventive measure, add a little sand to the bottom of the planting hole to improve drainage.