How to grow ranunculus

How to grow Ranunculus

Ranunculus are cool season perennials with exquisite, multilayered flowers that come in stunning hues of red, orange, pink and yellow, to name just a few! Ranunculus are a natural fit for, beds and containers.  Their long-lasting, origami-like flowers and straight stems make them excellent as cut flowers. So, if you are not already growing ranunculus, you should definitely start now! Here’s how…

When and Where to Plant Ranunculus

Though often referred to as a bulb, ranunculus occurs as a corm—a uniform, undifferentiated structure composed of stem tissue, specifically developed for the purpose of storing food. Ranunculus does best in regions with mild winters and long, cool springs. Fall is the ideal planting time in such areas. Those with colder winters can plant in late winter–early spring, once the threat of hard frosts is over. Ranunculus can grow well in zones 3–10 but you must lift in zones 3-7.

Photograph of a Ranunculus growth culture

How to Plant Ranunculus

When you are ready to plant ranunculus, you should soak them in room temperature water for 3-4 hours. Keeping water running on them will allow more oxygen to the corm.  Now this is the fun part, as they soak, they will double in size looking like a little octopus! This gives them a little head start to growing those beautiful blooms.  And if you want even more of a head start you can pre-sprout the soaked corms. Fill a tray with moist soil like a seed starting tray.  Cover the corms with the moist soil and place under a grow light in a cool place (around 50º F) like a basement.  Check them every few days and after 10 days you should have sprouted ranunculus and you are ready to plant in your beds if there is no threat to frost.

Soaking Ranunculus in water:

Photograph of soaking Ranunculus in water

After soaking corm doubles in size:

Photograph of Ranunculus corm after soaking

Pre-Sprouted Ranunculus after 10-14 days:

Photograph of pre-sprouted Ranunculus after 10 to 14 days

How to Grow Ranunculus in Outdoor Garden Beds

A sunny site with rich, well drained soil is ideal for growing ranunculus. If the ground is susceptible to puddles after hard rains, it’s advisable you enhance the drainage and raise the soil level by adding at least 2–3 inches of compost, peat moss or other organic material.

Ranunculus corms have pointed ends that look a lot like claws. Make sure these “claw-ends” are facing down as you plant them, 1–2 inches deep, 4–6 inches apart. Water well after planting and apply a 2–3 inches layer of mulch to help conserve moisture that’s paramount to the plants’ early growth. You’ll start to see floral growth within 90 days of planting.

Resist the urge to cut off the faded foliage after ranunculus flowers have finished blooming. The faded leaves are still pretty useful as they continue to gather sunlight and prepare for next season. The foliage usually dies back by the end of summer at which point you can completely remove it. The plants will remain inactive for the next few months and then start all over again.

Make sure you irrigate regularly during the growing period and stop once the plants have gone dormant.

How to Grow Ranunculus in Tubs or Containers

Pick a container that’s large enough to accommodate the full grown plant and has adequate drainage holes to prevent water logging. Fill in with quality well draining soil. Find your container a spot that receives full sun for at least 6 hours a day.

Dig 2” deep holes and plant the corms with the “claw-ends” pointing down. Space adjacent corms 4–6 inches apart. Water well to help the soil settle down around the corms. Keep an eye on the soil during the initial growing phase, irrigating regularly to keep it from drying out.

Ranunculus planted in fall start to bloom early in the spring season, flowering continuously for a period of 6–7 weeks. Corms planted in late winter begin to flower by mid-spring and usually remain in bloom for 4–6 weeks.

Leave the spent foliage in place so it can gather sunlight and provide nourishment for next season’s growth. The foliage will die back on its own by summer end and can be removed completely.

Irrigate the plants regularly while they’re active. Once they’ve gone dormant, you can stop watering altogether.

Using Ranunculus as Cut Flowers

It’s not without good reason ranunculus flowers are so popular as cut flowers—they can last indoors for up to 10 days after cutting! You can cut the blooms the day you notice color in the buds. The buds will feel squishy to touch at this point. Cut your flowers early in the mornings, when they’ve had had a good rest and access to moisture, factors that will help them survive longer in bouquets and other floral arrangements.

Few endeavors are as effortlessly rewarding as growing ranunculus—a couple careful steps will make your garden the object of everyone’s envy!

Shop All Ranunculus