Q: My plant does this every year. Could you explain what goes on and why? The white cornlike thing comes out in the evenings and is closed during the day and doesn’t come back out again. In a week or two, they all fall off after the pods open up and tightly close.
Julie Sweeny, Roseville
A: According to UC master gardener Annie Kempees, Monstera deliciosa – also known as split-leaf philodendron and commonly called the fruit salad plant – is a species of flowering plant native to tropical rainforests of southern Mexico, south to Panama. The specific epithet deliciosa means “delicious,” referring to the edible fruit. (The “fruit salad” nickname also refers to the fruit, which tastes like a cross between pineapple and banana.)
When growing outside, if the conditions are right, the Monstera might start blooming three years after being planted. Flowering is rare when grown indoors.
This member of the arum family Araceae is an epiphyte with aerial roots. Like a vine, it’s able to grow up to 65 feet high – especially if it has a large tree for support – with large, leathery, glossy, heart-shaped split leaves, 9 to 35 inches long and nearly as wide.
In the Sacramento area, these plants need protection when grown outdoors. Foliage is damaged at 32 degrees and colder.
The flowers, which are like huge arum lilies, appear on short thick stems during the summer if humidity conditions are good. The central spadix develops into a cylindrical dark green fruit, 8 to 10 inches long and 2 to 3 inches in diameter.
All parts of the plant are poisonous except for the ripe fruit. The fruit of Monstera deliciosa looks like a green ear of corn covered with hexagonal scales. When it is on the plant and green, the unripe fruit also is poisonous, as it often contains raphides (needle-shaped crystals of calcium oxalate) and trichosclereids (hard, needlelike branched cells found in some species of plants that serve the purpose of protecting the plant from herbivores).
The unripe green fruit can irritate the throat; the latex of the leaves and vines can create rashes in the skin because both contain potassium oxalate.
Editor’s note: The ripe fruit takes 12 to 18 months to mature, so you’ve probably never seen it on your plant. To ripen, the fruit needs ideal growing conditions (such as tropical heat and humidity). What you’re likely observing is the plant shedding its spent flowers without the fruit development.
Otherwise, that cornlike center would gradually be replaced by its strange, scaly green fruit. When mature, the large and chunky six-sided green scales start to fall away naturally, revealing what looks like white pineapple flesh. That’s the “delicious” edible part of this “monster” fruit.
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