Relocation time again! Move your cactus pot back inside when nighttime temperatures are reliably staying under the 50ºF mark or 10ºC.
Discontinue feeding. This is the final call to apply any residual fertilizer.
Slightly decrease the watering volume.
Initiate the famous, mandatory dark treatment: The plant requires 12 to 14 hours of total, unbroken darkness every single night for six consecutive weeks. Any light source (even a tiny bedside lamp!) will ruin the signal.
A combination of short days, long nights, and coolness is the absolute key to successfully triggering flower bud formation.
Note: A follower asked us on Facebook if moonlight counts during the darkness treatment. The good news is no, the moon won’t mess with your cactus! Only artificial light leaks (lamps, TVs, streetlights through the window) can interrupt the bloom cycle.
October: Bud Formation
If September was a success, you should start seeing results now. The long nights must continue, without exception.
The nightly darkness mandate remains in effect. Don’t let the plant see the light of the day (or bulb!) before its 12 to 14 hours are up.
Try to keep night temperatures in the range of 50-55°F (10-13°C) because cooler air will set the buds.
Restrict water intake. Only provide a minimal amount of water when the soil feels mostly dry.
Fertilizer is still off-limits.
By late October, your hard work should pay off! Tiny, cutesy, distinct flower buds will become visible on the tips of the stem segments.
November: Protect the Buds
The flowers are teeny, fragile, and prone to panic. Your only job now is to keep them from throwing a fit and dropping off the plant.
As soon as the buds peek out, you can end the darkness treatment. Just this once more, it’s relocation time again. Move the cactus pot to a place with bright but indirect light and avoid placing it anywhere the sun hits it directly.
This is 100% non-negotiable: Now that the cactus is settled in its final November spot, do not move or turn the plant. Moving it even slightly can cause the fragile buds to suddenly drop.
Return to a light watering schedule to sustain the flower development.
Your singular focus is to help the buds successfully develop and swell into mature flowers without suffering any shock.
