Ranunculus are beautiful spring blooming flowers that add a pop of color to gardens, floral arrangements, and events. Their ruffled, rose-like blooms come in a rainbow of colors like pink, red, yellow, orange, purple, and white. Many people wonder if they can plant ranunculus in the spring or if they need to be planted in the fall. The answer is that ranunculus can be planted in spring or fall depending on your location and growing setup. In this article, we’ll cover when and how to plant ranunculus corms for a bountiful spring bloom.
When to Plant Ranunculus
Ranunculus can be planted in either the spring or fall depending on your climate and growing conditions. Here’s an overview of planting times:
Spring Planting
- Best for zones 3-8
- Plant March-April for bloom in May-June
- Start corms indoors 6-8 weeks before planting out
- Use a cold frame or hoop house to protect from frost
Fall Planting
- Best for zones 7-10
- Plant September-November for bloom in March-May
- Corms require 6-10 weeks vernalization period under 55°F
- Use a hoop house, cold frame or mulch for overwintering
Where you live will be the biggest determining factor in when to plant. In cold winter climates, spring planting is best so the corms don’t freeze over winter. In mild winter climates, a fall planting will yield earlier blooms. Many growers do successional plantings in both seasons for extended harvests.
How to Plant Ranunculus in Spring
Planting ranunculus in spring takes some preparation but yields beautiful blooms. Follow these steps for spring planting success:
1. Start Corms Indoors
About 6-8 weeks before your last spring frost date, wake up ranunculus corms by soaking in room temperature water for 2-4 hours. Next, place presprouted corms in trays with seed starting mix. Keep moist and between 60-70°F until sprouted.
2. Prepare Garden Bed
Choose a site with full sun and well-draining soil Incorporate compost and fertilizer, then create rows spaced 12” apart. Install hoop house or cold frame over bed for frost protection.
3. Transplant Corms Outdoors
Wait until daytime temps are above 50°F to transplant sprouted corms outdoors. Space corms 6-8” apart in rows at a depth of 1-2” Water well after planting and provide frost protection at night.
4. Maintain Consistent Moisture
Ranunculus prefer consistent moisture, about 1” per week. Use drip irrigation or hand watering to maintain even soil moisture. Avoid waterlogged soil which can cause rot.
5. Stake Plants
Once they reach 6-8” tall, stake ranunculus stems to prevent flopping. Use bamboo stakes and plant ties to secure stems.
6. Control Pests
Scout for common pests like aphids, thrips and botrytis. Take preventative measures and use organic pest control methods as needed.
7. Harvest Blooms
Ranunculus blooms can be cut when in tight bud to fully open. Harvest in the morning and place immediately in water. Remove foliage that will sit below the waterline.
With the right climate and care, spring planted ranunculus will bloom prolifically in late spring and early summer. Protect them from frost and pests for the best results.
Growing Ranunculus in Different Zones
When and how you plant ranunculus depends on which USDA Hardiness Zone you live in. Here are some zone specific tips:
Zones 3-6
- Spring plant after all chance of frost
- Use cold frame or hoop house for protection
- Mulch heavily for winter if fall planting
Zones 7-8
- Spring or fall planting
- Unheated hoop house recommended
- Provide frost protection as needed
Zones 9-10
- Fall planting ideal
- Bloom late winter into spring
- Can be left untreated in garden
Understanding your specific climate will help determine the ideal planting time. Warmer zones can plant in fall for early blooms but will need to provide chilling period first. Colder zones will have success spring planting under protection.
Choosing the Best Ranunculus Varieties
One of the fun parts of growing ranunculus is selecting from the many color varieties. Here are some top picks:
- Pink: Sweetheart Pink, Pink Haze, Amandine Pink
- Red: Magic Red, Scarlet Sprite, Red Royal
- White: Ice White, Polar Ice, White Magic
- Yellow: Yellow Magic, Citronita, Milestone Yellow
- Orange: Flamingo, Hot Orange, Mango Tango
- Purple: Plum Purple, Amethyst, Violet
- Mixed: Mondeo Mix, Sorbet Mix, Picotee Mix
Go for a single color for bold impact or try a mix for a rainbow effect. Be sure to check flowering times so all varieties reach peak bloom together.
Tips for Healthy Ranunculus Plants
Follow these tips throughout the growing season for thriving ranunculus plants:
- Plant large, healthy corms for best results
- Provide consistent moisture but avoid saturated soil
- Stake stems when 6-8” tall to prevent flopping
- Mulch plants to retain moisture and suppress weeds
- Scout for pests like aphids and treat promptly
- Deadhead spent blooms to encourage more buds
- Harvest frequently for maximum blooms
A little extra care will keep your ranunculus happy and blooming prolifically in spring.
Common Ranunculus Growing Problems
Even with the best care, ranunculus can run into problems. Here are some common issues and solutions:
Leggy, floppy plants: Give more sunlight, use larger corms, stake stems
Rotted corms: Improve drainage, avoid overwatering, treat with fungicide before planting
Distorted leaves: Indicates salt buildup in soil, flush soil regularly
Pests: Treat aphids, thrips, botrytis with organic sprays
Small blooms: Increase sunlight, use larger corms, ensure adequate moisture
Failure to bloom: Corms too small, vernalization period too short, planted too late
Catch problems early and adjust care to get your ranunculus back on track.
How to Harvest and Enjoy Ranunculus
One of the best parts of growing ranunculus is getting to harvest and enjoy the gorgeous blooms. Here are some tips:
- Cut stems when buds first show color for longest vase life
- Harvest in early morning when stems are hydrated
- Immediately place in cool water to maintain freshness
- Remove any leaves that will sit below the waterline
- Enjoy in bouquets, centerpieces, and flower crowns
- Ranunculus also make beautiful wedding flowers
With proper care, each ranunculus stem can produce 25+ blooms over a 4-6 week period. Harvest frequently to maximize the yield.
Extend the Season with Succession Planting
While individual ranunculus plants bloom for 4-6 weeks, you can extend the harvest by succession planting.
Stagger your planting dates by 2-3 weeks from February through April. Use cold frames or hoop houses to control conditions for each planting. This will provide blooms from early spring through early summer.
In mild climates, fall succession planting from September through November will give blooms in late winter and early spring.
Enjoy Colorful Ranunculus All Spring Long
With their rose-like blooms in rainbow colors, ranunculus are a star of the spring garden. By following the best planting and care practices for your zone, you can enjoy a bountiful ranunculus harvest. Use cold frames, hoop houses, and succession planting to maximize blooms from early spring into summer. Incorporate these cheerful flowers into bouquets, centerpieces, and events for weeks of enjoyment. With proper care, ranunculus are sure to give you a beautiful and rewarding spring bloom.
Growing Conditions + Where to Plant
We have widely varying winter weather here in Western North Carolina (zone 6b/7a). It can be in the upper 60s during the day one day and only 25 degrees at night the next. To have a little more control over the environment, I like to plant ranunculus and anemone in a hoop house, which is a small greenhouse-like structure that is not heated. However, you can also plant them under layers of Remay or light-filtering frost cloth (you want to let the light in, not keep it out). Depending on where you will plant (hoop house or field), you will need to change the time you plant. If you have a hoop house, you can plant earlier in the winter because the plants will be safer from freezing as they are inside. If you want to plant outside, you should wait until later in the winter when temperatures change less often and less drastically.
For the most part, I leave the end walls of our hoop house open all winter, unless it gets below 20 degrees F (-6 degrees Celsius). When it gets down to the 20s, I close the end walls of the hoop houses all the way and put a layer of Remay frost cloth over the plants. I uncover in the morning as soon as it starts to warm up. Ranunculus and anemone are prone to root rot and fungal diseases, so they need to be able to breathe and drain well.
When the ground is completely dry, I use the walk-behind tiller to go over the bed. I start with a light till, then a deeper till, and finally a light till to make the bed smooth. Before During After.
Our hoop houses are 14″ wide, which means I can fit 3 rows in each one. That leaves 2 very narrow paths that are each about 18″ wide. I’d rather have narrow paths that make the most of the growing space, but I’m okay with feeling a little awkward on the paths for now. After tilling, I put down woven landscape fabric that can be used again and again in the paths so that they don’t need to be weeded or maintained. I don’t plant ranunculus or anemones right into landscape fabric because the extra heat is bad for these flowers. I use a rake to mix organic compost and fertilizer into the soil in each bed after tilling the soil and putting down fabric in the paths.
About 10-14 days before Im ready to plant in the soil, I soak and pre-sprout the corms. Ill usually prepare the planting beds after Ive started this process. There are many different ways to pre-sprout your corms and I have had success by keeping it simple. Because ranunculus and anemone can get bacterial problems and it rains a lot here in the winter, I soak my corms in an organic bacterial fungicide solution. Bacterial fungicide is a concentrated good microorganism that sticks to the roots of plants. You can buy it online or at most home gardening stores. (I also use it to drench all lisianthus plugs before planting and have eliminated fungal issues. (I try not to use chemicals, but this product is approved for certified organic production and helps protect the corms I spent a lot of money on.) Root Shield and Actinovate are two brands that I recommend.
I let ranunculus and anemone corms soak for two to four hours, or until they start to get bigger. When the seeds are ready, put about 2 inches of seed starting soil in the bottom trays that don’t have holes. These are often called 1020s. I put each corm in the tray so that the “legs” of the ranunculus are facing down and the corms touch but don’t touch each other. Place anemone corms in any direction. Cover with a light dusting of the seed starting soil or vermiculite.
The temperature in my basement, which is about 60 degrees Fahrenheit (15 degrees Celsius), the humidity is moderate, and there isn’t much light. This is the perfect place to start sprouting. I check the corms every few days to make sure the soil is slightly moist, but not damp. Err on the side of too dry rather than too wet. After about 10 days, the corms grow little white rootlets and theyre ready to go. I get so busy around this time of year that they already have 1/2″ white sprouts when I get around to planting. No need to worry, they continue growing in the soil just fine.
I use landscape fabric to grow almost everything on the farm, but I don’t plant ranunculus or anemone into it. I have found that the anemone leaves and flowers get stuck under the fabric, and the ranunculus plants don’t like how the fabric keeps in more heat and water. Also, I have more time to pull weeds in the winter and early spring before the plants get too big.
I typically plant 4 rows per bed of ranunculus and 5 of anemone with six-inch6″ spacing. I made a super high-tech planting spacer out of a conduit pole and flagging tape. With the spacer, one person plants the sprouted corms along the rows, and the next person plants them about 1 to 2 inches deep. My favorite planting tool is also super fancy: a butter knife from Goodwill. It’s amazing how quickly you can plant a few thousand plants using this method!.
If the soil isn’t already very wet, I might give it a quick spray of water afterward. If I’m planting in a hoop house, I set up drip irrigation so that I can water plants occasionally over the winter. I only water when the next day and night will be above freezing, so the roots don’t freeze. I water more frequently in the spring. Ranunculus and anemone grow quickly and don’t need much care during the winter, just a few weedings and some protection from the really cold nights. 4 weeks after planting.
GROWING RANUNCULUS FROM START TO FINISH: HOW TO PLANT RANUNCULUS CORMS in BOTH SPRING AND FALL
FAQ
Will ranunculus bloom if planted in spring?
What month is best to plant ranunculus?
Do ranunculus come back every year?
Is it too late to start ranunculus?
When should I plant Ranunculus?
For colder winters, you will have to plant corms in the spring. You can start the corms indoors in late winter. They can be planted outside once the threat of a deep freeze has passed. This occurs approximately a month before the last frost. Ranunculus will only grow back as perennials in zones 8-10.
Can you grow Ranunculus from seeds?
Plant corms with the tuberous roots facing down at a depth of 2 inches and space plantings 9 inches apart. Most ranunculus flowers are grown from corms; however, it is possible to produce them from seeds. The seeds should be started indoors about 12 weeks before the average date of your last spring frost.
When do Ranunculus Bloom?
When planted in the spring, they should flower at end of spring or the beginning of summer and last for 4-6 weeks. When planted in the fall, they will bloom in mid-spring and last for 6-7 weeks. As ranunculus grow throughout the spring, consider using a frost cloth to protect the plants if it dips below freezing. Ranunculus should be deadheaded.
How do you grow Ranunculus in the fall?
Prepare indoor container-grown ranunculus in the fall. Soak the corms for four to six hours before planting them in a pot. Use loam-based compost with 20 percent horticultural grit and a slow-release fertilizer added to help with drainage and plant health.