Ranunculus Care Guide: How to Grow Ranunculus

Ranunculus are cool-season flowers that come in a variety of hues ranging from pale yellow and soft pink to bright orange and deep burgundy. Their rose-like petals are thin and delicate. No matter what variety you're planting, ranunculus make great companions to other spring flowers such as anemones, bloomingdales, dahlias, daffodils, pansies, picotees, primrose, and snapdragons. When planted in the right conditions, ranunculus flowers yield an impressive harvest.

Ranunculus bulbs—technically called corms—require a bit of care to grow properly.

• Determine your hardiness zone. Hardiness zones are specified by the USDA and range from 1 to 10. Ranunculus flowers prefer areas with mild winters and long springs, or hardiness zones 8 to 10, where the ideal planting time is the fall or late winter. This will yield an early spring bloom that will continue for six to seven weeks. If you plant ranunculus flowers in hardiness zones between 4 and 8, you'll want to plant them after the last frost in late spring for a late-summer bloom.
• Store the corms properly. If you're not quite ready to plant your corms, or it’s still too cold out, brush off all the excess dirt and place the tubers in a box with slightly moistened peat moss. Store them in a cool, dry place (50 degrees Fahrenheit) until planting season.
• Soak your corms before planting. For the best results, soak your ranunculus corms in room-temperature water for at least three to four hours before planting. This helps jump-start their growth. You'll know your corms are ready once they've doubled in size and sprout white, hair-like roots. They could rot if they get waterlogged, so set a timer when soaking your corms so as not to forget them.
• Plant them in well-draining soil. While moist soil is important, soggy soil can cause root rot. Plant ranunculus in an area that drains well or use well-draining potting soil in your cutting garden.
• Plant your corms in full sun. Ranunculus should be planted in areas with full sun. As is common with spring flowers, they need full sun but don't do well in high temperatures.
• Space the plants appropriately. Plant your corms two to three inches deep and four to six inches apart. Each corm contains multiple buds that will produce several flowers, and spacing them out will give the plants room to grow.
• Scatter mulch around the flowers. Mulch will help the soil retain moisture critical to the flowers’ early growth and allow you to water the flowerbed less. Mulch may also help keep the soil cool as the weather warms up, allowing the flowers to last longer.

With a few simple techniques, you can enjoy ranunculus flowers for months.

• Keep them moist. Keep mature ranunculus moist but not wet. Allow them to fully dry out between waterings.
• Fertilize ranunculus bimonthly. Using liquid plant food twice a month will help the plants produce more flowers and extend their life.
• Deadhead spent blooms. Once your ranunculus flowers are blooming, you'll want to deadhead them, or remove the dead flowers. Deadheading will help the plants maximize their growth.
• Stop watering in the fall. When the warmer months come to an end, ranunculus leaves will start to turn yellow and thin out. Stop watering your plants so the bulbs can dry out and you can store them for next season.
• Cut ranunculus before they’ve unfurled. Ranunculus flowers have an impressive vase life, often lasting longer than 10 days. For the longest vase life, cut the flowers when they're soft and vibrant but have yet to unfurl. If you cannot cut them before they unfurl, they will likely last about a week in a vase. Be careful when transporting them, as their petals are very fragile once opened.

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