As we discover the world around us, every so often we come upon something that surprises us to the point that we are just plain astounded. Such was the case for me some twenty-five years ago, when I visited Quail Botanical Gardens (in Encinitas, San Diego County) for the first time and saw a twenty-five-foot-tall, tropical-looking tree covered with…daisies? Soft-wooded but massive, it looked like a chrysanthemum on steroids. Nicely displayed at the edge of the central lawn area, this tree had a thick basal trunk, about eighteen inches in diameter, from which many smaller trunks grew. Its dense foliage of felty, gray green leaves was truly impressive, with each leaf up to a foot across. The real surprise, though, was its flowers—both individually and for their sheer numbers. Simply put, I had never expected to see little white daisies on a tree! And not just a few daisies, but up to a hundred to a bunch. And not just a few bunches, but well over 250 clusters of flowers that completely covered the tree!
Do the math: that’s over 25,000 daisies all at once! Did I mention that I was impressed? Well, I was—so much so that I made it my goal to become the caretaker of this tree, and, a few years later, I moved to San Diego to work at Quail Botanical Gardens. It didn’t take long before this tree became the “mother” of many, many offspring.
Made In Central America
This giant daisy tree (Podachaenium eminens) is in fact one of the largest daisies in the world—a giant member of the Helianthus tribe of the daisy family (Asteraceae). Native from Southern Mexico to Costa Rica, it is related to other cultivated daisy trees, such as those in the genus Montanoa (see Pacific Horticulture, Sum ’91 and Fall ’99), but is larger, more tree-like, and flowers in spring and early summer instead of fall and winter. A native of montane cloud forests, it is most at home in frost-free climates; however, mature plants will recover quickly from temperatures at least as low as 25° F. The flowering period of giant daisy tree here is generally from April to June, which avoids the problem of frosted flowers that other types of daisy trees may have. Magnificent in bloom, it is covered with twelve- to eighteen-inch wide terminal clusters of many sweetly scented, inch-wide, white daisies with golden yellow centers. These are followed by small gray seed heads that persist on the tree, the tiny seeds providing food for small seed-eating birds. The large leaves, six- to twelve-inches wide, are soft, fragrant, and shallowly-lobed; both new leaves and stems are covered with soft gray pubescence. Unpruned, giant daisy tree grows naturally as a multi-trunked, spreading tree, quickly reaching its mature size of twenty-five feet by twenty-five feet.
To say that giant daisy tree is fast growing is an understatement. In fact, it is one of the fastest-growing plants I have ever observed. Shrubby when young, a two- or five-gallon nursery plant can easily attain both a height and width of eight feet within a year of planting, with adequate water, and will double that size in two years. Unlike other trees, there’s no need to wait a generation for this one to mature, since a full-sized tree can be had in as little as five years. Plant it in full sun or light shade in almost any type of soil and water regularly (I water mine once a week in the dry season). The ideal climate for growing giant daisy tree as a tree is neither too hot nor too cold, as might be found in Sunset zones 16 to 24. It definitely excels in coastal climates of Southern California, where it has been cultivated (though not commonly) for at least seventy-five years; it also grew well in Santa Cruz and does not mind cool temperatures, even those in the thirties. However, its large leaves deserve protection from frost and strong winds.
More Than A Tree…
Despite its handsome proportions in cultivation here, giant daisy tree in the wild is often seen growing as a large shrub, particularly as an understory plant. Due to its rapid growth rate, it is one of my favorite plants for an ultra-quick shrubby screen—and it has done a heroic job for me. A couple of years ago, it became apparent that the once-peaceful country road near our house had finally and irreversibly become too noisy, due to the increased traffic of commuters using it as a shortcut. I wished that my fence were twenty feet tall. While I did not have the resources to construct a fence of that height, I did have some two-gallon plants of giant daisy tree. I planted four of them along the fence line at ten-foot intervals; within a year, they were already eight feet tall and nearly as wide. Now, just two-and-a-half years after planting, I have my twenty-foot-tall fence—complete with attractive foliage and thousands of white flowers each spring.
A little bit of pruning can keep Podachaenium eminens dense and shrubby. In fact, you’ll get lots of lush growth above each cut with even bigger leaves than normal. If cold temperatures in winter are a problem, it’s nice to know that plants are quite happy under the frost-protective shade of larger trees. Although the foliage of giant daisy tree will be damaged in a frost, a mature plant has the ability to resprout quickly from its stems or from its base, and grow happily as a large shrub.
It’s A Good Friend
I’ve always been impressed with big, bold plants, and always loved the tropics. Giant daisy tree is big, bold, and tropical—and we can grow it! Sad to say, my old friend at Quail Botanical Gardens died of old age a few years back (it was close to fifty years old—a great age for a soft-wooded tree). Fortunately, I anticipated this twenty years ago and planted a young, cutting-grown plant nearby, so that, today, you can still see a giant daisy tree near the central lawn and gazebo at the gardens. You can also look for Podachaenium eminens at your local botanical gardens and rare-plant nurseries.