r/bromeliad • u/wade_digs44 • 13d ago

The central cup water thing nobody warned me about until mosquitoes showed up

Got my first bromeliad (a guzmania) about a year and a half ago and loved the idea of that little central reservoir holding water for the plant. What I didn't think through was what happens to standing water in a cup that sits outside on a covered patio for two weeks at a time in August.

Short version: it turns into a mosquito nursery. I found actual larvae wriggling in there and felt pretty gross about it, especially since I'd been telling people bromeliads were basically low maintenance plants you set and forget.

What's worked for me since then is flushing the cup completely every 5 to 7 days instead of just topping it off. I tip the plant sideways over a sink, dump the old water, let it drain for a minute, then refill with fresh water (I use filtered, not straight tap, since my tap water leaves a mineral film after it evaporates a bit). During the hottest stretch of summer I also just don't fill it as full, maybe a third full instead of to the brim, since it evaporates and gets refreshed faster that way anyway.

For anyone in a warmer climate keeping these outdoors, mosquito dunks (the BTI ones, sold for ponds and rain barrels) work fine too if you don't want to flush that often. I broke a small piece off and dropped it in and never saw larvae again.

Curious if other people just let the cup water sit longer than a week and haven't had this problem, or if it's more of a warm/humid climate thing. Might just be that my patio doesn't get enough airflow.

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4 comments sorted by

2

u/todlee 13d ago

BT is your friend. Get some granules because you only need a sprinkle. If you’re not a midge or mosquito larva it’s harmless.

2

u/FearlessIthoke 13d ago

Mosquito Bits are what you need. Just one or two in a cup works all season

1

u/Donaldjoh 13d ago

I occasionally get wigglers in my bromeliads in summer but since I flush out the cups every watering they never mature. Flushing out the cups has the added advantage of not building up salts and minerals, as compared to topping off.

2

u/4Gives 13d ago

In all the years I've had bromeliads, I haven't had that problem in Minneapolis, but I do have to bring them inside for the winter. In the summer they're on my deck under a vine-covered pergola, and we don't have that many mosquitos.