How to Grow Sunflowers Indoors (Easy Step-by-Step Guide for Beginners & Kids)

Growing sunflowers indoors is easier than you might think — and it’s a wonderful activity for children and beginners alike. Plus, it’s one of the few living things in my house that doesn’t ask for snacks every 15 minutes. With the right variety, a sunny windowsill, and a little daily care, you can enjoy these cheerful blooms without even stepping outside. Here’s exactly how to grow sunflowers indoors from seed in 10 simple steps.

Planting Sunflowers With My Little Duckling

What You’ll Need to Grow Sunflowers Indoors

• Pot – at least 15–20cm wide for dwarf sunflowers, or 30cm+ for tall varieties

• Good drainage – holes in the base + saucer to catch water

• Multipurpose compost – peat-free, ideally with added slow-release fertiliser

• Sunflower seeds – dwarf varieties like Teddy Bear or Big Smile work best indoors

• Small trowel or spoon for planting

• Watering can, a cup or spray bottle

Step-by-Step: How to Plant Sunflower Seeds Indoors

1. Choose the right sunflower variety

For indoor growing, pick dwarf sunflowers that grow to around 40–60cm tall. Taller varieties can be started indoors but will need to be moved outside once they outgrow your space.

2. Prepare your pot for sunflower planting

Choose a pot with drainage holes and place a thin layer of stones or broken pottery at the bottom. This prevents waterlogging, which can cause root rot.

3. Add compost

Fill the pot with peat-free multipurpose compost until about 2cm from the rim, leaving space for watering.

4. Sow your sunflower seeds

Make a hole 1.5–2cm deep in the centre of the soil. Drop in 1–2 seeds, cover with compost, and gently press down.

5. Water your sunflower gently

Use a watering can with a fine rose or a spray bottle to keep soil evenly moist without washing away the seeds.

6. Give your sunflower plenty of light

Place your pot in the sunniest spot possible — ideally a south-facing windowsill — so it gets 6–8 hours of sunlight daily.

7. Check soil moisture daily

Water when the top 2–3cm of soil feels dry. Avoid letting the pot sit in standing water.

8. Support the stem

Once your sunflower seedling reaches 15cm tall, insert a small bamboo cane and tie loosely with soft string for support.

9. Feed your sunflower for bigger blooms

After 3–4 weeks, give your plant a weekly feed with liquid tomato fertiliser to encourage strong stems and vibrant flowers.

10. Help with pollination if indoors

If you want seeds and your sunflower stays indoors, mimic bee pollination by gently brushing the flower’s centre with a soft paintbrush.

Lots of Fun with Bugs and Soil

Extra Indoor Sunflower Growing Tips

• Plant several seeds in different pots for a better chance of success.

• Turn your sunflower pot every few days to help it grow straight.

• Keep a sunflower growth diary with children — measuring, drawing, or photographing the plant each week makes a great keepsake. I love adding recordings like these with my son to his journal (a simple A3 sketchbook). I will share it on a separate post soon!

Recommended Resources

• Messy play tray – our favourite tray for sensory bins and messy play

• The Life Cycle of Flowers – a beautifully illustrated book that helps children understand how flowers grow and change

  
  

Final Thoughts 🌞

Sunflowers are low-maintenance, cheerful, and endlessly fascinating for little ones to watch — and unlike certain members of the household, they don’t mind wearing the same clothes every day. Whether your sunflower ends up as a proud kitchen windowsill feature or a towering garden giant, it’s a simple project that gives a huge sense of achievement.

Once the seeds are planted, give yourself a few peaceful minutes to enjoy a coffee by letting the children carry on playing with the soil. To keep things stress-free, set it up on a messy tray like this one, or cover the floor or table with a wipeable cloth.

Let me know how it goes! :)

Until next time,

Itala