Drainage on plant pots indoors, plus mosquitos
October 14, 2022 12:27 AM   Subscribe

We are expecting a lot of houseplants soon, and are trying to figure out how to best handle pots for these plants. They will arrive in standard plastic pots and we want to either put those inside caches/cover pots, or repot them. These plants will sit on top of shelves, cabinets and floors and we are puzzled how people handle water and soil dripping from the drainage holes post-watering. This is complicated by living in a dengue zone so we can't have standing water. What's the smart solution?
posted by dorothyisunderwood to Home & Garden (19 answers total) 2 users marked this as a favorite
I dislike mosquitoes fiercely, and have many houseplants. First to protect furniture, all of my plants sit either on saucers to ensure any errant drips are caught, or are in plastic pots in a decorative ceramic pot that has no drainage (the decorative pot acts as oversized saucer), or for the big floor ones, on a saucer with wheels.

Depending on the plant, and my mood, I either take all plants into the bathtub every other week, let them have a 10-15 min shower and then they drain in bathtub until no longer drippy, or I water sparingly, making sure there is no standing water in saucer after ~1hour. I am vigilant about standing water, so I set a timer after watering to check.

I actually find outdoor plants in pots with saucers much more able to breed insects; one has to keep an eye out for standing water post storm. If this feels like a lot, I've built it into my evening routine, and jokingly refer to it as surveying my farm. (Takes less than 5mins to confirm there's no standing water, or that if plants need it they get water. Sometimes the plants get the shower in the evening, cause then they drain all night, and also bonus plants in shower making mornings delightful.)
posted by larthegreat at 1:39 AM on October 14, 2022 [6 favorites]

Response by poster: To add: I have bought a water meter to help with when to water and they are all shade-tolerant and with light.
posted by dorothyisunderwood at 1:39 AM on October 14, 2022

I asked my gardener friend in KL, who lives for these types of question because responding to commonly found internet advice with inherited advice from gardening in the tropics is her jam. So, this is her direct response:

Use saucers under the pots, or put the pots into planters (which can look nicer but be aware that water won't evaporate as fast compared to saucers). DO NOT BE TEMPTED TO BUY POTS WITH NO DRAINAGE HOLES. I don't care what the internet says, drainage is key for root health in humid equatorial climates. Add more perlite or other drainage-improving soil amenders to the potting mix.

Just use mosquito larvacides such as Abate and Bti. Add them regularly into the saucers as per package instructions.

Honestly, if the water evaporates fast enough they won't have to worry about mosquitoes.

posted by cendawanita at 3:03 AM on October 14, 2022 [3 favorites]

I put an inch or two of small clay balls into the bottom of pots that lack drainage holes. They soak up extra water and release it slowly.
posted by nouvelle-personne at 4:21 AM on October 14, 2022 [3 favorites]

I use the kind of plant pots with a hole in the bottom and it sits in a saucer. And I've heard that it's actually good to dump the water in the saucer out after about 15-20 minutes anyway; you water your plant and some of the water will come out into the saucer at first, but let it sit about 15-20 minutes and some of that water will get soaked back up into the pot. Then you dump out the rest.

(Actually, truth be told is that sometimes too much water is coming out of the bottom and it's in danger of overflowing and I worry about overspill, so I usually dump some of the excess water from the saucer into another plant right away. And THEN I dump out excess water again after 15-20 minutes.)
posted by EmpressCallipygos at 4:33 AM on October 14, 2022 [1 favorite]

I have several dozen houseplants so I have to water them in place, to help manage and get rid of insects, including mosquitos I like to use the following:
(1) Heavy Duty Plastic Saucers/Trays -- All my plants are in pots with drainage holes or cachepots.
These heavy duty trays are great for when you need to move plants around, I've had too many mishaps with flimsier trays. Having clear trays also means you can see when to use...
(2 )Mosquito Bits, you can just sprinkle a few bits in each tray or in cachepots. You can use this stuff anywhere there is standing water, indoors or outdoors.
(3) Bonide Systemic Insect Control Granules for when you repot, just sprinkle over the top layer of soil and mix in the top inch or so; other option is to mix directly into the soil when you repot
(4) Yellow sticky traps, these are just good to help as you transition these plants into your home and work on implementing these other preventative measures.
posted by SoulOnIce at 4:57 AM on October 14, 2022 [2 favorites]

Perhaps not the solution you were looking for directly - but there are those who choose the grow the plants hydroponically in a water container - then fill that water with fish like medakas that like to chomp on mosquito larvae. Something like this - or this or maybe this.
posted by rongorongo at 5:49 AM on October 14, 2022 [1 favorite]

I keep most of my plants in their grow pots and put that inside another pot. I usually water them in the bathtub or the kitchen sink and let them drain for a while. But there are a couple I water in situ, those I just water a little bit at a time and more often so they don't overflow the drip tray underneath. Trust me, you'll overflow the drip tray once and then you'll absolutely know how much to put in.

I use the planta app to keep track of everything and remind me when to do something if that might be helpful to you. It was super helpful when I was first getting plants as I felt like I didn't know what to do.
posted by magnetsphere at 6:05 AM on October 14, 2022

I am a big advocate of putting plants into _huge_ containers. For house plants, this means multiple plants in one container. This does make it harder to re-pot them later, but the huge containers make little "gardens" that are really, really lovely.

The main reason I do this is this: the large volume of soil will almost never dry out, so, for most of the tropical plants that are common in homes, they don't have to be watered very often -- and when they are watered, you don't have to do it so much that water runs out the bottom.

** Instead of mosquitos, your main flying insect issue (at least in my climate) might be fungus gnats. Check incoming purchased plants carefully, put bacillus thuringiensis on top of most soil if you can, and make sure the top surface doesn't stay soggy if you can avoid it.
posted by amtho at 6:06 AM on October 14, 2022 [3 favorites]

I don't have a worry about mosquitoes breeding indoors (at last, a benefit of a cold climate!), but rarely have an issue with standing water related to my houseplants. They are all in what I call liner pots, which have drainage holes in the bottom, and plunked into decorative pots for, well, decorative purposes. To water them, I put the liner pots into a sink (or tub) filled with a few inches of water and let them soak up what they need. After about 15 minutes, I pull the plug and let the excess water drain out. Say, another five minutes or so. Then they go straight back into their decorative pots. I do this weekly.
posted by DrGail at 7:03 AM on October 14, 2022 [1 favorite]

I just put them in the sink and water them there, then they can hang out and drain for a while. We have one massive plant that can’t go in the sink, that gets watered in the bathtub.
posted by cakelite at 7:42 AM on October 14, 2022

Like cakelite, I move the pots to the sink (a bucket would also work) to water them, wait for them to drain, and then return them to the decorative outer pot, which doesn't need to have holes.
posted by pipeski at 8:56 AM on October 14, 2022

Okay, so for the pots you can reach: water the plants slowly so you don't get too much overflow (this is a learning process), and then give them 20-30 minutes to soak up the overflow. For the extra: dump it out (if you can), use a turkey baster to soak the water back up, or soak up with a ratty old towel. You will definitely want to put the saucers on top of something else to protect your floors, especially if they are clay pots.

For my pots that hang or are on top of cabinets, I take them down to water them and water them in the sink or tub and let them drain for a while there. There's no easy short cut otherwise, especially if you don't want any standing water.

Agree with others that you want drainage holes. You can put plastic pots in more attractive outer pots, but you can't leave the cache pots with water in them for the health of the plant, never mind mosquitos.

I would also say "a lot of houseplants" if you don't already have experience with this is a big job! This is a lot to take on. Can you ramp up slowly with a few at a time?
posted by bluedaisy at 11:22 AM on October 14, 2022

Look for nice looking water proof trays that would look good on top of your book cases, or use disposable waterproof trays, such as a foil turkey roasting pan cut down so it isn't too tall, inside a decorative one that can't handle the water. Lining a tray with a plastic sheet to protect it tends to fail; a smaller tray inside the decorative one is better.

The trays will protect your furniture from accidental drips and over flows but also make it easier to tend a host of small pots because you can lift the whole thing down to a convenient height to mass prune or pinch flower buds.

At the very least lay plastic on the top of surfaces that are above eye level. This will spare the furniture from getting those water damage rings when just a little water over flows unseen.
posted by Jane the Brown at 12:16 PM on October 14, 2022

I am right in the middle of this very thing. Here is my solution. I am moving three huge pots back to a friend's house who thought she was moving forever. Two aloes, and one, huge asparagus fern. They will be on a covered back deck, with nice padded tiles of some sort. There are grooves I can run tubing through. So, I bought 25 feet of 3/8 clear plastic tubing. I am just now going out for metal screen, silicone sealant, and pea gravel. After washing out these pots, and letting them dry, I will stick the tubing into the drainhole with 4 inches of tubing left inside the pot. I will put a long skinny nail horizontally through the tube, so the ends of the nail won't let the tube fall out, ever. I will splay/cut the tubing 4 ways starting 3/8 inch above the nail. I will fold out those four sides along the bottom of the pot. and glue them down with silicone sealant. I will cut a round of screen that goes to the edges of the pot and maybe curve up the sides a bit. I will lay a bead of silicone sealant where the screen meets the pot, on the outer edge of the screen. The silicone bead will be under the screen edge and press up through it. Then I will go over the inner edge of the screen so the silicone sealant keeps drainage at least sieved clear of matter that could plug the drain hose. I will put pea gravel in the pot up to the silicone line, after the silicone dries.These drain lines will go over the edge of the deck, and likely be held to the side of the deck, by cup hooks. The hooks will just be orderly guides. The drain tubes empty onto a lower flower bed. Getting 25 feet of tubing, rather than 10', guaranteed me enough and not much more was spent on 25' than I would have spent on 10. I happen to have a lot of bigger cup hooks and I think they will make innocuous guides. I may have to make an extra side hole in the foot of the two matching pots, so I don't mash the hose as it comes out of the bottom. The big fern is trickier, as it is in an at least 10 gallon pot which sits up on a piece of wood, an 18 inch thick like pie slice, from a 100 year old cedar tree. I will drill the trunk obliquely so the drain hose goes out the back side. I am moving the aloes from one set of pots to the drained pots I fix up. I have another giant pot the same as the fern's pot to set up, so it is also a transfer. I just have to draw with a sharpie around tha big fern pot so using geometry I can find where the drain will go on the wood. The pot overhangs the wood on the pointy end of that pie shape.

Clear tubing comes in all sizes, in this case the plants are large and the covered porch is new, and needs to stay looking that way. The previous owner zen gardened the whole small back yard it is all gravel and concrete, with olive trees across the back.
posted by Oyéah at 2:58 PM on October 14, 2022

I also have plants in the plastic liner (with holes) + decorative cache pot (no hole) setup.

Also, consider the technique of "watering from the bottom"--instead of pouring water onto the soil, pour into the outer container and have the plant soak/wick it up through the drainage holes. Cuts down on splashing, and helps keep the top of the soil not too soggy (lower risk of fungus gnats and overwatering).
posted by Sockin'inthefreeworld at 3:44 PM on October 14, 2022

Response by poster: Thank you! Cache pots and sink watering seem like the best solution, possibly with some clay beads at the bottom. I have many dumb cats and don't want to risk insecticide in case they try to drink any of the water ever.

I plan to try the 'small plants in a big pot tiny garden' as well, plus the planta ap rec, too.

Re: influx of plants, we pick a single item to exchange at Christmas and this year will be plants, adding up to about 30+ plants in December. We are still working our way through the previous years' mugs and socks.
posted by dorothyisunderwood at 6:37 PM on October 14, 2022

Just pick your plants very carefully, some of them would hate to be in a big damp pot because they’d rather dry out thoroughly between waterings.

A lot of the skill in houseplants is understanding that it is NOT one size fits all. Learn about each individual species you receive and what it prefers. For plants that want to stay moist, plastic pots inside a decorative pot with no drainage is good. For plants that like to dry out, clay pot with a saucer is better.
posted by lydhre at 4:13 AM on October 16, 2022

Mosquito bits or mosquito dunks (active ingredient: bacillus thurengenesis aka bti) are harmless for pets and humans! You can keep one in your watering can or add to soil.

Nematodes from NemaKnights will look after fungus gnats (agree that these are a big pain in the ass.)

I avoid plastic pots completely, and I agree that pots without drainage holes are just not worth it, ever. Terra cotta only for me, with plastic or glazed ceramic saucers. You can get white and grey unglazed ceramic pots now if the burnt sienna is not your fave.
posted by sixswitch at 1:39 PM on October 16, 2022 [1 favorite]

« Older Downtown Austin for Pedestrians   |   What are some oils/creams to help fade a neck scar... Newer »
This thread is closed to new comments.