How to Grow Ranunculus

Everybody wants a garden filled with colour, and ranunculus bulbs bloom into a wide spectrum of colours, heights, and forms, meaning you can fill your garden with these popular spring flowering bulbs. Whether you are looking to grow them in your flower garden or in pots across a balcony, knowing how to grow ranunculus bulbs is essential for all flower enthusiasts.

Get the best vase life out of your ranunculus bulbs by learning how to plant ranunculus bulbs and the right time to harvest their blooms.

Ranunculus Classification

Family

Ranunculaceae.

Genus

Ranunculus asiaticus.

Ranunculus Varieties

There are over 1,700 different varieties of ranunculus worldwide and here in Australia, there are many varieties that can help bring a myriad of colours to your garden. Some of the most popular colours include:

• White Ranunculus
• Yellow Ranunculus
• Pink Ranunculus
• Red Ranunculus
• Pastel Ranunculus
• Burgundy Ranunculus

Ranunculus come in dwarf varieties growing to around 25cm tall, and regular varieties that grow to between 40 and 60cm in height.

Ranunculus plants grow best in rich soil with plenty of organic matter. There are plenty of steps you can take to ensure that your soil is well-prepared for growing ranunculus. First, remove any weeds from the soil and loosen the soil by digging it up to at least a spade's depth. Add in compost to cover the soil and lightly mix into the soil to combine it.

Ranunculus prefer well-drained soil, so if your soil is heavy or struggles to drain, you can alleviate the issue by planting in a pot or trough that has holes for drainage. Now all you need to do is wait for the right conditions to plant your ranunculus!

Knowing the right time to plant Ranunculus bulbs is perhaps the most important part of growing these beautiful flowers. We recommend planting your bulbs anywhere from late summer through to winter.

When planting ranunculus, begin by soaking their corms in room temperature water for up to an hour before planting. Next, place them into the prepared soil at intervals of 15 cm at a depth of 6cm. Ensure that you place their claws downward and thoroughly water them once they are planted and covered. Water them weekly until shoots emerge, then water as needed.

Where to Plant Ranunculus Bulbs

Ensure that you plant your bulbs in full sun in a location that will see at least six hours of sunlight.

How to Grow Ranunculus Bulbs

During the growing season, your ranunculus plants need watering whenever the soil is dry to 5 cm below the surface. You can check this by moving the soil with your fingers or with your favourite gardening tools. Water deeply in the early morning or late afternoon. Your plants will begin to flower in the warmer Spring months.

Deadhead Regularly

As the ranunculus flowers grow, be sure to deadhead regularly using pruning tools to remove any dead or dying flowers above the leaves. Removing all dead flowers will encourage the plant to produce more flowers.

Fertilise the Bulbs

Once your flower buds begin to appear, introduce some liquid fertiliser formulated for flowers to your soil. You can also add an additional application of fertiliser once the flowers are finished growing to improve the following year’s display.

Pest and Disease Advice

Numerous forms of pests and diseases can pose a threat to your Ranunculus plants. Knowing how to deal with them is just as important as knowing how to prevent them.

Pests

Some common pests that can be an issue if left unchecked include aphids, slugs, and snails. Aphids are small sap-sucking insects that cause leaves to become discoloured and wilt. Located on shoots and the underside of leaves, they will excrete honeydew that can attract other pets, such as ants. Aphids can be removed with a quick spray of the garden hose or a soap spray to coat the leaves and shoots.

Slugs and snails eat tender leaves and shoots, and because they are most active at night, they can be a nightmare to deal with. Luckily, they leave a trail behind, meaning you can find them and remove them. You can also place traps to deter them and remove their hiding places, typically dark corners filled with damp or rotting organic material.

Diseases

Mildew is a fungal disease that causes the leaves and shoots to weaken, eventually causing the plant to die. The two types of mildew that affect Ranunculus are downy mildew and powdery mildew.

Downy mildew produces yellow to grey-brown patches to appear on the underside of the leaves. To remove the downy mildew, water the plant at the soil level, carefully avoiding the leaves. Remove any leaves that are affected and ensure the plant isn't overcrowded. If you notice the problem persisting, then a fungicide will do the job.

Powdery mildew is caused by fungal spores that reproduce on the leaves of the ranunculus, initially showing as white spots before spreading rapidly across the affected areas of the plant. Powdery mildew is unlikely to kill the plant but is unsightly. To remove powdery mildew, water the plant at the soil level, preventing the spores from spreading further. Remove any affected leaves; if the issue persists, an appropriate fungicide will handle the fungus.

Companion Plants

If you’re looking for the perfect plants to grow alongside your ranunculus, then we have a great selection of flower seeds to choose from including:

• Calendula Seeds
• African Daisy
• Snapdragon
• Pansies
• Sweet Pea Seeds

All of these flowers make great companion plants for your ranunculus, allowing you to have a garden blooming with colour and a wide selection of incredible plant varieties.

If you’re looking to enjoy the longest vase life possible for your ranunculus flowers, we’d recommend harvesting your blooms just as the buds are beginning to unfurl. This way, you can flaunt your stunning home-grown flowers inside for as long as possible.

Once cut, ranunculus flowers will last up to a couple of weeks in a vase when provided with clean water and kept in cool conditions and are guaranteed to add some stunning colour to your home for their duration!

Be sure to leave your ranunculus corms in the ground. Storage can damage your corms, meaning that they grow weaker and produce fewer flowers when replanted the following year. You should confidently get a solid 2 years out of corms before needing to plant new ones!