How to Grow Sunflowers
There’s nothing quite like a sunflower for making a big statement in your garden! Ranging
from huge varieties over six feet tall to dwarf sunflowers compact enough to grow in pots, there’s one to suit every space.
As well as the familiar golden-yellow flowerheads, you can now grow red, orange, pink and even green sunflowers, and they’re good for wildlifefriendly gardens, attracting both birds and bees. Sunflowers are easy to grow from seed and
a great way to introduce kids to gardening!
When your plants arrive
-
Unpack your plants immediately and check the compost to ensure it has not dried out in
transit. Water with a fine spray, or sit the plants in a tray of shallow water if the compost is
dry. -
Pot on plug plants as soon as possible (preferably within 24 hours) after they have had time
to settle.
Potting on and planting out plug plants
- Handle each plant by the plug root ball, rather than the stem to avoid damage.
-
Pot each plug into a 7.5cm (3in) pot using a good multi-purpose compost or a
container compost. -
Grow on for a few weeks in a greenhouse or a bright, frost-free place, but avoid
direct sunlight. -
Keep moist but do not over-water. If very cold weather is forecast, cover with a layer
of fleece. -
Once there is no more danger of frost, the plants can be moved to their permanent
position. -
Harden off your plants before planting them out by placing the pots outside during
the day and bringing them back in at night. After 7-10 days, the plants will be ready
to plant out.
How to care for Sunflowers from Seed
-
Sow sunflower seeds indoors in April, 1.5cm deep in individual small pots filled with
moist multipurpose compost. Seal each pot inside a clear plastic bag and place
somewhere warm and bright (but out of direct sunlight) to germinate. -
Once the seeds have germinated, remove the plastic bags. Grow on until the
seedlings are big enough to plant out, after the last frosts. -
You can also sow sunflower seeds directly outdoors in late May. Dig the soil over
first, removing any weeds and large stones, and dig in plenty of well-rotted farmyard
manure or other organic material before sowing. Rake the soil to produce a level
surface with a fine, crumbly texture. - Sow the seeds 1.5cm deep and 10 cm apart. Water well after sowing.
- Thin seedlings to 45cm apart.
How to care for Sunflowers
-
Plant sunflowers in fertile, well-drained soil in full sun. Dwarf sunflowers can be
grown in containers filled with multipurpose compost. -
Put in strong stakes for tall varieties when planting them, and tie the plants in to the
stakes as they grow. -
Once flowers appear, feed the plants weekly with a liquid high-potash feed such as
tomato feed. - Water regularly, especially in dry periods.
-
To harvest sunflower seeds, cut the flowerheads off once the petals have faded and
store them in a sunny, warm, dry place for a week. To remove the seeds, gently rub
the seedheads. - As the flowers fade, leave a few seedheads on the plants to provide food for birds.
- When the plants die back in autumn, pull them up and compost them.
Pests and Diseases
Nemesia may be prone to the following pests and diseases. Read more about how to control
common plant pests and diseases here.
Pests
- Aphids
Diseases
- Generally disease-free
