From the funny little tubers that look like little bunches of brown bananas sprout ranunculus. They are Southern California’s favorite bulbs, and no other flower is so riotous in spring. This is the time to plant ranunculus tubers, but first the good news, and then a little advice.
Last year, you might have noticed ranunculus being sold in pots at nurseries, even late in the spring. Some of those were grown from the tubers planted in containers and treated with growth regulator to be shorter than normal. But many were grown from seed, a new strain developed in Japan. Called Bloomingdale, it had a number of nursery people and gardeners excited, because, for the first time, ranunculus could be planted late in the season and still make a reasonable show. They also observed that the stems were shorter and sturdier than those of other ranunculus; that not only makes overhead watering easier (which is required frequently when ranunculus are planted as the weather is warming), but it also makes this ranunculus a good container plant.
Although the Bloomingdale strain is seldom labeled as such, you can usually recognize it because it grows no taller than a foot. The same bright colors are available but are generally not sold separately, so to get a certain color, you must buy the plants in bloom.
That’s the news. The advice is that unless you are gardening in containers or in a very small space, perhaps you should wait to plant these.
Tubers, however, should be planted right away. Planting tubers is a lot less expensive than trying to fill a whole plot from pots. Also, tubers produce bigger flowers and more of them. The growers in San Diego County have counted as many as 150 flowers coming from a single jumbo tuber, though you’d be doing well to get half as many. Also, tubers are sold as separate colors, which lets you concoct dramatic planting schemes such as the one shown here. If you want to follow the riotous route, look for mixes of these brilliant colors.
As an incidental note, it has been suggested that ranunculus and anemones be planted together, as if they were very similar plants--a natural twosome. My experience is that they have little in common. Ranunculus are so much brighter and bolder and bigger than anemones that the smaller flowers become lost, even though they can contribute a reasonably good blue to the color scheme. Also, anemones, though still reasonably easy to grow, are more difficult than ranunculus. But rather than mixing the two, plant them in different places, where they won’t compete for attention or care.
Ranunculus tubers have a somewhat tarnished reputation, that of being hard to get started. Plant them six to eight inches apart and so that only an inch of soil covers them. (Unlike tulips, these tubers do not need refrigerating.) The one secret to success is not to over-water them at first. Like many bulbs, tubers that have not yet grown roots may rot if they are kept too wet. An old wives’ tale advises soaking the bulbs in water before planting, but as one grower said, “They can’t swim” and shouldn’t be soaked. An old rule of thumb that does apply is to water the tubers once, but very thoroughly, after planting and then not again until they sprout through the soil. If two weeks go by with no signs of life, forget the rules and water again, and then wait some more.
Success is almost guaranteed that way, though watch out for birds. Those little denizens of the air can descend and nibble the sprouting ranunculus before you are awake, and you’ll never be the wiser. If you see any birds in the flower beds, assume the worst and cover the plantings with one of the commercial bird nettings sold at nurseries. Be sure to prop the netting up on short stakes so that the emerging plants don’t become entangled in it. Once the plants are three inches tall, the covering can be removed.
Ranunculus must be grown in a full day of full sun; otherwise, they’ll be weak and tend to topple. Once growing, they need adequate water, but not so much that the soil hasn’t a chance to dry out a little. They also should be fertilized. Many people assume that everything a bulb needs is stored inside, but in the case of ranunculus, what’s inside is just enough to get them started. Six to eight weeks after planting, sprinkle any brand of granular fertilizer around the bases of the plants, and water it into the soil. Use the amount that the label suggests for flowers.
A month after that, fertilize again, this time with a liquid fertilizer. At this stage you don’t want to risk getting grains of concentrated fertilizer lodged between the leaves or petals. If any diluted liquid fertilizer gets on the foliage, it will only help, and that is one way to green up leaves that are turning a little yellow (if it is not from over-watering). Liquid fertilizers, incidentally, seem to be a little more effective in winter.
Planted now, ranunculus grown from tubers will flower in early spring, and if you haven’t had enough by then, remove them (there’s little point in saving them) and plant the seed-grown kinds, for another month of flowers.
For that matter, whenever a hole appears in the garden, add ranunculus to the list of suitable plants that can be purchased in flower for instant effect. And add the Bloomingdale strain of ranunculus to the list of flowers that excel in pots.