Ranunculus (Persian buttercups) are more likely to be seen in a floral shop or bridal bouquet than in a garden, unless the climate is mild Southern California. These flowers, which bloom in spring, are brightly colored and long-lasting, making them a favorite of commercial florists. If you want to grow ranunculus, it is easier than you might think. The bulbs are inexpensive and widely available. Ranunculus are frost-tender, but they can be grown as annuals in most climates.
Grower and floral designer Erin Benzakein says that it is impossible not to fall head over heels for the many wonderful qualities of these beauties. Some of these qualities include tall stems, double-ruffled blooms, a light citrusy rose fragrance, high productivity, and one of the widest color ranges imaginable.
RANUNCULUS BASICS
Botanical name:
The Ranunculus asiaticus derives its name from the Latin word for frog, “rana”, because it prefers wet growing conditions.
Common name:
Persian buttercup
Zones:
This plant can survive in climates that range from hot to cold, but it will only last one year in areas that are colder than zone 7.
Bloom time:
Early spring to summer, depending on the climate.
Cultivars:
There are two strains of R. asiaticus that are commonly cultivated for home gardens. The flowers of both strains are cup-shaped and look like a hybrid of a peony and a tea rose. The flowers have abundant layers of papery petals set off by feathery parsley-like leaves.
- ‘Giant Tecolote’ produces large double-flowered blooms up to 6 inches wide on stems as tall as 2 feet. It comes in almost every color except blue, and some of the most exotic varieties have green centers, variegated petals, and picotee edges.
- The less common ‘Bloomingdale’ hybrid is a dwarf variety that produces the same lush petal-packed blooms but on shorter, sturdier stems 8 to 10 inches high.
Habitat & Growing Conditions
Garden Ranunculus flowers do not grow well in hot, humid conditions or in soils that are too damp. They grow best in well-drained soils that are light in color and prefer climates that are cool.
The tubers are not fully hardy and will not survive a long period of time in cold weather.
The ideal climate for these plants includes mild winters, cool springs, and summers that are neither too hot nor too wet.
Garden Ranunculus has a hardiness rating of H4, which means it can withstand most of the United Kingdom’s climate.
One’s success in planting and growing Ranunculus in the UK is largely influenced by one’s location choices.
Where to Plant Garden Ranunculus
Ranunculus can be used in many different ways in a garden. They are good for courtyard gardens, city gardens, and formal gardens.
A bunch of different plants in one big area will look really pretty because of the different colors and shapes of the blooms. Or, if you just want one plant, get a really nice one and put it by your front door.
Ranunculus also make good companion plants, for example try pairing yellow and orange Ranunculus with blue and purple Delphiniums.
Rich Yellow Ranunculus Varieties – Excellent Companions for Delphiniums
Feeding, Care & Growing Tips
You can plant Garden Ranunculus tubers in spring or fall so that they will produce flowers in summer or winter. The flowering season will last for five weeks, stretching to six.
If your summers are not too hot and humid, you can enjoy Ranunculus flowers in the summer as well as in the spring.
Aspect
These plants should be in full sun in most parts of the UK, except for the warmest areas. Otherwise, they should get six hours of morning sun.
Soil Requirements
A soil with a lot of sand and no clay, amended with organic compost or humus down to 7 to 8 centimetres, is perfect for these plants.
The soil pH should be in the range of 6.1 to 7.3 for best results.
This plant’s tubers will rot if the soil does not drain well.
You can improve drainage for your plants by adding gravel to the bottom layer of their home, or by mixing in perlite. You can also make it easier for water to drain by planting the tubers in ridges or mounds.
You can also plant Ranunculus tubers in a container that is the right size.
Tubers
There are four grades of Ranunculus tubers that are sold commercially, with Jumbo being the largest and Number Three being the smallest.
Jumbos are the largest size of potato, about 2.5 centimetres wide. The other grades are progressively smaller. (The classification and nomenclature used here are American. Dutch bulb merchants and growers classify and name tubers somewhat differently.)
You can plant a large number of less expensive, less floriferous Number Two tubers if you intend to grow Ranunculus in a sizeable bed.
Jumbos are the best type of plant to buy for growing in containers and for specimen plants. The tubers should be dry, firm, and without any nicks or blemishes.
Planting
You can soak the tubers in water for an hour or two before planting them, but don’t soak them for any longer.
If you are in a region that is Zone 3 or warmer, you can plant tubers in November, early spring, or both. Keep in mind that the tubers need temperatures of 9° to 13° centigrade to germinate.
If the average temperature is not within the specified range, then the tuber needs to be germinated indoors or under glass in controlled conditions.
Tubers should be planted 4 centimetres deep. Jumbo tubers should be spaced 25 centimetres apart; Number Two tubers should be spaced 13 centimetres apart.
They must be planted with the ‘claws’, from which the roots will grow, downward. Fill up the hole with dirt until it is level with the ground and gently push the dirt down so that it is compact.
Watering
Water your plants well after you plant them. You can put a thin layer of hay, straw, or bark around them as mulch.
Water the plants twice or three times a week, making sure the soil neither becomes waterlogged nor dries out completely during the initial growing phase.
The plants will need less water once they are established, and no water once they have lost their leaves and are dormant.
Fertilising
Feed the plants with a 5-10-10 slow-release fertiliser at the beginning of spring, or mix in bonemeal into the soil several centimetres away from the tubers at the end of spring.
Overwintering
Whether you should lift the tubers of Ranunculus for the winter or not depends on your precise location, the possibility of a hard frost, and the kind of soil you have prepared.
If you live in a region with harsh winters, if you expect a long period of frost, if your soil doesn’t drain well, or if you expect a rainy summer, you should dig up the tubers and store them indoors until it’s time to plant them again. Otherwise, you can just get rid of them and buy new tubers next season.
To avoid having to remove tubers and replant them, you can grow Ranunculus in appropriately-sized containers.
Cut off the tops of your tubers, allow them to dry out in a cool, dry, dark room, and store them in a similar environment. lightly pack them in peat moss and put them in a mesh bag.
After they bloom:
Although ranunculus flowers are beautiful, they don’t last very long. They thrive in cool temperatures but start to die when it gets hot outside and the ground warms up. Since ranunculus bulbs are cheap, most people grow them for one season and then throw them away. If you want to try to keep them alive, you can dig up the bulbs, cut off the dead leaves, and store them in a cool, dry place.
Pruning Guidelines
Cut flowers for indoor display just after the buds have begun to open and colour for the longest lasting results. Flowers cut in the morning hours will last longer.
deadheading flowers encourages new growth.
You shouldn’t cut off yellowing or wilting leaves because they help provide energy to the plant, which helps prepare it for the next season.
Only remove leaves from the plant once they have died at the end of the season.
Common Problems
In spite of their delicate and refined look, Ranunculus are actually quite hardy plants that don’t often get pests or diseases. The only things you need to be careful of are aphids and powdery mildew.
There are organic ways to get rid of aphids, such as using BotaniGard ES or Safer’s soap. Follow the instructions on the packaging for how much to use.
If you find powdery mildew on a plant, cut off the affected parts and remove them from the area promptly.
Make sure the plant gets enough sun and isn’t crowded by other plants. Water at the base of the plant so the leaves don’t get wet to avoid mildew.
IDEAS FOR USING RANUNCULUS
In the garden:
Did you know that you can buy ranunculus bulbs in single colors? This gives you the opportunity to create your own unique color combinations. Ranunculus are cool-season spring bloomers, so they look great when planted with other cool-season annuals and perennials such as snapdragons, violas, Virginia bluebells, oriental poppies, late-flowering daffodils, and peonies.
In floral arrangements:
Ranunculus can adapt to a wide range of growing conditions as long as you give them full sun, sufficient moisture, and soil with good drainage. However, they cannot tolerate warm and wet conditions, which may lead to rotting, according to the NGA.
- Cut stems when the buds are colored and squishy like a marshmallow, but not yet fully open, recommends Benzakein. If the blooms are open when you take cuttings, they will still last a week but will be more fragile. When your cut flowers start to droop and the stems begin to bend, cut the stems short and cluster them in a smaller vase so you can make your cuttings last a few more days.
- Ranunculus in a spring mix does the job that a rose or peony might do later in the season. “The ranunculus is the perfect alternative to a real rose. I often use ranunculus in spring floristry and am surprised at how frequently I’m asked which rose they are,” says flower artisan Georgie Newberry, author of Grow Your Own Wedding Flowers.
- Pure white ranunculus (such as white Tecolote) is especially popular in spring bridal bouquets. It blends in with any color scheme, but also looks lovely alone or mixed with other white flowers like jasmine or lily-of-the-valley.
- The delicate, hollow stems of ranunculus are prone to rot, so be sure to keep the water level in the vase low, advise Alethea Harampolis and Jill Rizzo, authors of The Flower Recipe Book. One of their favorite “recipes” for displaying ranunculus is very simply, in a round ceramic vase with the leaves removed from the stems to create a clustered bouquet. Or arrange them in vintage fruit cans with colorful labels that will complement the flowers’ cheery colors
Where to Buy Garden Ranunculus
– Garden Ranunculus can be bought as potted plants or tubers.
You may be able to find a few varieties of potted plants at the more well-stocked nurseries during the spring flowering season.
You can tubers from either online or brick-and-mortar stores that specialize in bulbs and seeds.
It may be difficult to find Garden Ranunculus tubers from British sites online, but you will probably have more success finding them from American bulb merchants. Many American bulb merchants sell a wide variety of Garden Ranunculus tubers.