There are several reasons why holiday cacti tend to drop their buds: They’re confused.
Usualy, that means they got the wrong message from you about the temperature or light in there environment.
Why Holiday Cacti Drop Their Buds
Remember, not all holiday cacti is the same kind. There are actualy three separate species with slightly different requirements. Most of us group them together under “holiday cactus.”
How do you tell which species is which? Look at the leaf segment edges. If sharp-toothed, it’s a Thanksgiving cactus, and if rounded, it’s a Christmas cactus. If bristly pads covers the surface, it’s an Easter cactus.
Knowing the difference matter, since these plants don’t bloom at the same time. The Thanksgiving guys peak in late fall, the Christmas ones in midwinter, and Easter cacti want to bloom in springtime (they won’t force themselves to do otherwise).
How do you get flowers? Hint: It’s about making things cool, not feeding them more.
The thing with these guys is that they grow on Brazilian rock outcroppings, where it’s cool and airy, so cool temperatures (fiftyish during the night) are necessary. Actually, for the six weeks leading up to blooming time, the nights should of stayed around fifty degrees, roughly fifty to fifty-five degrees Fahrenheit.
If you’re indoors, your home is probably too warm telling the plant that it’s summer, when it just wants to make lots of green pad, not flowers. Bring the pot outside into an unheated porch or even a cooler room for six full weeks. Make sure it gets consistent coolness (and keep temperature steady).
The second essential element are light. To start bud set, these plants requires 14 hours of unbroken darkness each night. Bring them into a room with a light on, carry them through an illuminated hall, or have a security light bleed through a window, and that will reset plant’s internal clock. The plant think it is still day, which cancels out the bloom.
Don’t turn the pot, don’t move it around; put it in one place for the duration, where it gets bright indirect light by day and total darkness at night.
Because they are epiphytic (grow on tree trunk in their native habitat), watering’s easy. Use a loose, chunky potting medium containing some perlite or bark. They don’t like to sit in it. This means they’ll rot if the roots gets wet.
Wait until surface of the growing medium feels dry to the touch, then water thoroughly but drain the saucer completely within twenty minutes. Because good drainage is key, never leave them sitting in water.
From late winter through summer, feed the plant sparingly with half-strength balanced fertilizer. Stop all fertilizing during the cool period, as roots needs a rest.
Bring the plant back into a bright, draft-free spot when buds emerge and resume regular care once the blooms have faded. Prune carefuly then.
Remember: Shocking them by exposing them to sudden changes in temperature will cause bud drop.