How to Grow & Care for Ranunculus Flowers
Ranunculus (Ranunculus asiaticus) make the perfect spring and early summer cut flower. They grow from dormant corms (which look a bit like a dried up piece of bark or dried up claws) that are planted in autumn. Ranunculus prefer to grow in a full sun to part shade spot in a cool or temperate climate garden, but they will also tolerate the sub-tropics.
Ranunculus are fairly hardy plants, but they will need a moist (not soggy) soil from when they are planted right through until they finish flowering - so make sure they’re on an irrigation system or in a spot you can easily water. Avoid overhead watering if possible, because this can encourage fungal diseases on the leaves.
Grow ranunculus in pots or mass plant them in your garden for a big hit of colour. Their frilly flowers, on long stems come in a range of colours to suit all gardens.
5 top tips for growing ranunculus flowers
- Choose a full sun to semi-shade position in your garden or grow ranunculus in pots.
- Ranunculus need a free draining soil so the corms don’t rot. If your soil is heavy, choose to grow your ranunculus flowers in pots instead
- Ranunculus make great cut flowers, regularly picking the blooms will encourage more to follow.
- Fertilise ranunculus with a fertiliser designed for flowering plants during their growing season to encourage lots of blooms. Look out for Scotts Osmocote Pour+Feed for Flowering Plants
- Watch out for slugs and snails attacking the young shoots of ranunculus plants as they emerge from the ground - sprinkle around Defender Slug and Snail Pellets to control them if needed.
Essential shopping list for growing ranunculus
- Ranunculus corms
- Scotts Osmocote Compost Premium Soil Improver
- Scotts Osmocote Pour+Feed for Flowering Plants
- If growing in pots, Scotts Osmocote Plus Organics Premium Potting Mix
- Garden trowel
- Defender Pyrethrum Insect Spray
- Defender Slug and Snail Pellets
You’ll find dormant ranunculus corms for sale from late summer to early winter at your local nursery or garden centre - this is the best time to plant ranunculus corms.
Ranunculus prefer a full sun to semi shade spot in a free draining, compost rich soil. Prepare the soil for planting by digging Scotts Osmocote Compost Premium Soil Improver through the top 20cm of soil before planting.
If your soil is heavy or not free draining consider growing ranunculus in pots instead.
Planting ranunculus corms in the garden
Plant ranunculus corms into prepared soil 15cm apart and 4cm deep with the little ‘claws’ of the corm facing downwards. Once all the corms are planted and covered with soil, water them in well. Give the planted out area a weekly watering until the new shoots emerge and then water as needed.
Mulch around your ranunculus plants (once they’ve emerged from the ground) to retain moisture and suppress weeds.
Planting ranunculus in pots
You can grow ranunculus in pots - each corm will need 15cm of growing space, so choose a pot that fits as many corms as you need it to. Your pot should be at least 30cm deep and have plenty of drainage holes.
Fill your pot with a premium potting mix like Scotts Osmocote Plus Organics Premium Potting Mix before planting your ranunculus corms into it.
Water in the ranunculus corms and water them weekly until the new shoots emerge.
Mulch the top of the potting mix to retain moisture and ensure the pot can be easily watered during the flowering season.
Fertilising ranunculus flowers
Fertilise your ranunculus fortnightly once the new shoots emerge with a liquid fertiliser like Scotts Osmocote Pour+Feed for Flowering Plants. Continue to fertilise as the plant dies back at the end of summer to help it store energy for the coming season.
When is ranunculus season in Australia?
Use sharp scissors or secateurs to harvest ranunculus flowers to make floral arrangements. Cut down low on each flower stem, close to the plant - this will encourage further blooms.
Remove any dead flowers in the same way to encourage more flowers to follow.
Once the plants have completely died back in autumn, you can either lift the corms and replant them somewhere else or leave them in the ground to flower the following season. HINT - it’s a good idea to clearly mark where you’ve planted ranunculus so you don’t accidentally dig them up or disturb them when they are dormant.
Common ranunculus pests & diseases
The new shoots of ranunculus are susceptible to slug and snail attack. Use beer traps (saucers filled with beer placed on the soil surface) or sprinkle around Defender Slug and Snail Pellets to control these pests.
Reduce the risk of a powdery mildew outbreak on your ranunculus leaves by avoiding overhead watering when you can. If you spot any powdery mildew affected leaves, remove and dispose of them immediately.