So many Christmas cactus (Schlumbergera) owners are frustrated during the holidays when there isn’t a bloom in sight on their plants. What they don’t know is that they should have been setting the stage for those blossoms back in the summer. August to be exact. If you want blooms for the holidays, there are a few quick things you need to do this month.
What’s Happening to Your Plant This Month
By the time August rolls around, your plant begins setting the stage to shift from its active growing cycle into prepping for bud set later in the fall. All summer long, it’s been pumping every bit of energy into growing bigger by putting out new cladodes (leaf segments).
But as the month draws to a close, Christmas cactus will stop putting out new growth. They will start conserving energy to make buds. And as the days begin to shorten noticeably, now is the time to start prepping for the big holiday display to come.
Do This at the Beginning of August
If you haven’t already, put your Christmas cactus outside. Those of us in the know have had our Christmas cactus outdoors, tucked away out of direct sunlight, all summer. (Doing this each year is the absolute best way to ensure your plant is absolutely smothered in blossoms for the holidays. Read why here.)
You don’t want it sitting where it will get blasted by the sun.
It needs to have bright, indirect light. I put my Schlumbergera out on my front porch, but tucked it back in the shade. Here, they go nuts putting out tons of new growth all summer long.
Treat your Christmas cactus like your pale-skinned friend who burns easily. (I am that friend.) They need to be outside, but in the shade.
Even if you’ve only got a week or two left, that consistent, strong light will do wonders for creating lots of blooms.
Keep Watering Consistently
Christmas cacti do not like wet feet. But if you’ve got your plant outdoors, it will likely dry out much faster than it would indoors. Plus, all that growing requires a lot of water. Check your cactus frequently by sticking your finger in the soil. Water it when the top inch of soil is dry and give it a thorough soaking.
Let your plant soak up everything and drain for about fifteen minutes, then tip out any standing water.
Switch to a Fertilizer Meant for Blooms
During the active growing period of early spring through summer, I opt for a fertilizer with a higher nitrogen content. But when August rolls around, I reach for my secret weapon. (It’s this, this is my secret weapon. You can read more about it here.)
Don’t let the name fool you, I know it says African violet food. It works great for Christmas cactus, too.
It’s high in phosphorus and potassium, both important nutrients for blossom development.
I use this fertilizer at half strength nearly every week during August.
Do This at the End of August
At the end of the month, we’re going to make two abrupt changes that will ensure your plant begins bloom prepping.
Check For Stowaways
About a week before the end of the month, start checking your plant for signs of pests. Christmas cacti are one of those rare plants that don’t generally attract many pests. But with your plant sitting outside for most of the summer, you don’t want to take the chance that you are bringing in more than just a Christmas cactus.
Check the soil, look at the crown and don’t forget to look under cladodes. Be gentle, as the segments snap easily.
Bring Your Plant Inside
Now that your Schlumbergera has enjoyed its summer holiday outdoors, soaking up as much light as possible, it’s time to bring it home.
Bring your plant back inside at the very end of August. Place it somewhere away from other houseplants for a week or two. I know we’ve checked for stowaways, but it’s better to be safe than sorry.
Ensure your Christmas cactus is somewhere in your home where it will continue to receive bright, indirect light.
We’re not trying to kickstart the short-day photoperiod that will cause bloom set just yet. We’re simply allowing our plant time to acclimate to its new environment beforehand. It’s just like you returning from vacation, only your Christmas cactus doesn’t have an inbox full of unread emails.
Start Slowing Down on Water
We’re doing all of this in August because this is when your plant’s normal growth cycle begins to slow down in preparation for bloom set. To help with this transition, you’ll want to start easing up on how often you water.
As the plant slows its growth in time with the shortening days, it will naturally use less water. If we continue watering the way we did in the summertime, we’ll end up giving our plants root rot.
Now, we’re going to go from weekly watering to every other week.
Keep an eye on your plant; you don’t want the cladodes to start looking thin and wrinkled. They should remain plump between watering. But between being indoors, where the water will evaporate more slowly, and your plant using less water, you’ll naturally water less frequently.
Stop Fertilizing Altogether
Up until this point, we’ve been feeding a plant through its natural growing cycle and giving it fertilizer that provides the nutrients necessary for blooms.
Now we stop fertilizing for the year.
Your plant has everything it needs stored up, ready to go for the big show coming in the months ahead. In late winter, after blooming and a brief rest, your plant will start the entire process over again. It will come out of dormancy and begin its natural growth cycle, at which point you can resume fertilizing.
I know it’s tempting, but don’t fertilize your Christmas cactus from the end of August until late winter. You’ll do more harm than good.
One Thing You Should Never Do in August
When you bring your Christmas cactus indoors after being outside all summer, you might be tempted to repot your plant. This is probably the worst thing you could do right now. You’ll stress the plant and completely disrupt the process that has begun to create blooms in the months ahead.
Repotting is also counterintuitive now because Christmas cactuses need to be slightly root-bound to bloom well. These plants need to be repotted far less often than your average houseplant. Usually, once every 3-4 years is plenty. If you feel that your Christmas cactus is overdue for a new pot, wait until after the holidays before repotting it. You can read here about how and when to repot your Christmas cactus, plus how big a pot you should move up to.
And that’s all there is to it.
Consider your Christmas cactus to be like that one diehard friend who starts prepping for the holidays now. (We’ve all got one.) If you get on board with what your plant is already doing, there’s less of a rush, and the payoff is a magnificent Christmas cactus absolutely dripping in pink blooms through the holiday season.
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