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Discuss water requirements, "soil" (growing media) and suitable planting containers

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By Intheswamp
Posts:  3108
Joined:  Wed May 04, 2022 2:28 pm
Just bumping the thread with a slightly modified version of the initial post...for what it might be worth.

Mostly to do with flytraps, sundews, and pitchers...the little CP world I live in.

1. If at all possible, do purchase a TDS meter (~$15 on amazon). It makes life nice.
2. Use water that measures under 50ppm of TDS. (Some people's tap water is safe to use. Not mine, though. My tap water will eat the bumper off a Freightliner. )
3. Use most any water for a short period of time if #2 isn't available. Flush later with good water.
4. Not following #3 can result in quick plant death. Think "bleached cow skull in Death Valley".
5. Use distilled water, reverse osmosis (RO) water, rainwater, dehumidifier water, possibly AC water. Rainwater is my favorite.
6. Most of the above water can be used without testing with a TDS meter.
7. Rainwater is the least expensive, the TDS and the pH are usually good.
8. Rainwater TDS measurements will vary...rural lower, city higher, but either should be usable
9. I feel better using distilled water for seed-starting. No plant spores, fungus, etc.,.
10. I feel better using rainwater for growing/grown plants...cheaper, natural, it's cheaper.<g>
11. A 5-gallon bucket is great for catching/storing rainwater. They also are cheap ($5) or can be free.
12. Check bakeries for freebie buckets.
13. A 32-gallon Rubbermaid garbage can holds more, though, but they're $20...but they hold more!
14. Place containers beneath gutter spouts, roof drip lines, etc., to catch rain.
15. Do not catch the first few minutes of rainwater from the roof. It's dirty from roof debris
16. A few minutes later much of the debris will be rinsed off the roof...then start catching the water.
17. A (very) small 10'x10' roof can produce around 30 gallons of water from a 1/2" rain.
18. No roof? Hang a tarp between supports with a dip in the middle creating a low point that empties into a bucket. Maybe a 10'x12' tarp?
19. The hard-plastic kiddie pools that people use for bog garden containers work well simply set in the yard to collect rain. Heavy rains you get a lot, light rains not so much.
20. There's doggie-pools, too. TSC.
21. Your rain catchment system will not catch rain if it isn't set up when it rains.
22. Plastic cat litter boxes, emptied milk/tea/oj/water/etc jugs, are all good for water storage, too.
23. Do not use empty Round-Up jugs for water storage.
24. You might want to use mosquito bits or dunks if your water storage container is not completely sealed. But, remember that they will raise the TDS level.
25. Your rainwater might look a little murky, but your flytrap will love it! I prefer it to be clear, but...

Peat Moss:
1. Bales are much cheaper than small multi-quart packages but take up much more room for storage and can be a problem transporting if you don't have a vehicle that will carry them.
2. Small multi-quart packages "seem" to usually be good quality and also more expensive.
3. Quality seems to vary more with varies between brands and between batches of the same brands.
4. Never buy Greensmix peat moss from Tractor Supply (personal experience, YMMV).
5. I’m currently using Magic Earth peat moss.
6. In the past I usually rinsed my peat moss 2 or 3 times, letting it soak for a day or two in between a rinse and the next one. Squeeze the water out good each rinse. You'll never get it perfect. Now, I rinse it once, maybe twice and call it “good”.
7. A paint-strainer bag that fits inside a 5-gallon bucket helps keep things neat when rinsing peat moss. (Lowes/HomeDepot/Amazon). Strong recommendation. Some people don’t rinse, your choice.
8. Timing a good rain with a kiddie pool laid out to catch lots of water works great when it's peat moss washing time! Washing peat moss takes lots of low-TDS water!
9. It is recommended to wear gloves and a dust-mask when handling peat moss. It does carry some risks with it. Just sayin'....

1. Buy big bags if it is available that way, it's cheaper. I like Vigoro brand…big bag.
2. Rinse it!
3. Rinse it! I was shocked to see how milky the water became the first time I rinsed some perlite. Very milky looking. My understanding is that the processing plants use whatever nasty water that they have on hand to wet it with during its production to keep dust down. It could have been salty, alkaline, yucky water. I rinse it…good.
4. Wear a mask for this one, too, until you get it can be *really* dusty.
5. There’s never much said about perlite…just referred to in ratios. Sad.

Sphagnum moss:
1. I don't know enough about it to say much. (I don't know that much about the other things, but that didn't stop me with them, did it! )
2. Some people swear by it, some people curse it. I haven't gained enough knowledge and confidence to use it in great amounts. Peat moss is a bit more "forgiving" in regards to water retention...from what I've seen.
3. There is dried sphagnum and live sphagnum. Both look good and can be used for a top dressing. Live sphagnum looks really nice but beware that if you’re starting seeds you need to be sure the live moss doesn’t overshadow the new cp sprouts.
4. Live sphagnum can outgrow some CPs. It might need pruning back occasionally.
5. I wish I knew more than I do about sphagnum moss. I'll learn...slowly...maybe surely.
6. I do know that live sphagnum moss has some really good growth enhancers with it. Some plants just love it!

Sand - Coarse, #12, pure silica:
1. This is like...a chicken with teeth, a unicorn, the pot of gold at the end of the rainbow, an honest politician. From my experience...these things and coarse #12 sand do not exist.

Sand - "Other"
1. The key is to use *SILICA" sand. Other non-silica, non-quartz sands can leach minerals into the grow-mix which can harm your plants.
2. Finer grained sand is much more available, not as good as the coarser grade but usable.
3. Pool filter sand is often recommended. It is usually stated as #20 grade. I have heard mention of a "coarse" pool filter sand.
3. General "play sand" and "builders sand" are usually not recommended but sometimes they are found to be acceptable. It takes testing.
4. Put some sand in a glass and pour a depth (couple of inches?) of 5% vinegar over it. Let it sit for an amount of time (10 minutes?, a half hour?, 24 hours?) and then look for any fizzing, bubbling, foaming, big bubbles, little bubbles, etc., happening. The vinegar is reacting with non-silica grains in the sand being tested. If you see the fizzing and bubbling...don't use it.
5. Silica sand is quartz sand. The grains will be translucent to transparent...light will pass through them. They will not be opaque (no light passes through). The grains may be different colors, other than clear. But, mostly clear.
6. Sand helps increase drainage but really fine-grained sand can lead to soil compaction...not good.
7. Sand can be used as a top dressing to hinder algae growth, stop peat and perlite from getting splashed onto the plants from rain, etc.,. I haven't used sand much...but plan on using more in the future.

1. Use *rigid* plastic pots. Soft-sided pots flex too much when handled, shifting the grow-mix and disturbing the plant roots.
2. Do not use regular clay pots...they leach minerals into your grow-mix. Bad. Not good.
3. Glazed, ceramic pots can be ok...but they need to be sealed very well including the drain holes and bottom.
4. Full-sized (grown) plants...5" deep minimum....7" and deeper are even better.
5. Seed germination and small seedlings...3" deep pots seem to be fine.
6. Pots need plenty of drainage holes. An electric drill is your long as you don’t drill through your hand. Then it’s not a friend anymore.
7. Pots without holes can be transformed into a thing of beauty with the help from your "friend".
8. White pots are cooler than dark-colored pots.
9. Large Styrofoam cups are good pots...punch holes in the *sides* of the bottom. Flat-bottomed cups can have bottom-drilled drainage holes blocked by the surface they sit on.
10. You can put a pot down inside another pot to help create shade on the inner pot to help keep it cool. That was an interesting sentence…can you read it three times in a row?

1. I don't know enough to talk about it, but extreme caution is usually recommended.
2. Maxsea is kind of the base standard…it is used in a very diluted solution. Osmokote time release fertilizer pellets can be punched down into the soil around pitcher plants…only a few! It might even be best not to fertilize…you can kill your plants, ya know!

1. Same as fertilizing. I've tried it once so far with re-hydrated bloodworms. Not a memorable experience. I don't think I killed anything, though.
2. My plants have plenty of bugs so I don’t really try to feed anymore. Maybe they’d do better if I did. But, I don’t.

Light and Temperature:
1. Plants need light and many enjoy temperatures that you enjoy...maybe a tad warmer for flytraps and pitchers.
2. Flytraps and pitcher plants like full sun and enjoy it on the warm side. Windowsills don't cut it for them.
3. Most nepenthes like it more shadowy, maybe mottled shade, and maybe not as hot.
4. Some sundews, such as capensis, enjoy a little relief from the blistering sun and heat. Lots of them are happy on windowsills.
5. Other sundews, like filiformis and others like it HOT.
6. The other CPs...Most of them like it scolding-adz hot! Well, very warm. How’s that?
7. The hotter the temperature the more water they will need over time. Don’t miss checking them when it’s hot weather, especially if you have a spell of really hot weather. It only takes a half day to hurt them.

Ok, that's my psychotic ramblings for this morning. Actually, I'm just tired of thinking and writing.
All points are subject to change without notice. Vote early and vote often. Never miss an opportunity to visit the john. Things in your rear view mirror are closer than they appear. Side effects are: I *think* it's done. Check's in the mail. Etc.,.
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By andynorth
Posts:  1198
Joined:  Fri May 12, 2023 9:08 pm
Wow. This is awesome. The only thing I can not do is collecting rain water from the roof, which is unfortunate seeing's how I could fill 4 55 gallon drums in a day with the rain we get. However, up here in the PNW, if it's not moving it grows moss/mold. (Actually even if it does move) So myself and most others up here use either Moss out or zinc strips on our roofs to prevent this. Not so good for plants. Let it go for a year to collect water and I will spend next summer cleaning it all off. :D But Thank you for this. Great advice for all.
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By Intheswamp
Posts:  3108
Joined:  Wed May 04, 2022 2:28 pm
Use the suspended tarp idea. Depending on the layout of your place you could have it emptying into your rain barrel. With the frequent liquid sunshine ya'll get you could rig up a portable setup that you can put up and take down quickly. Fill your barrels/jugs and deploy the tarp when you start getting low.
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By Hedonista
Posts:  77
Joined:  Fri Jan 05, 2024 2:21 pm
This post is incredibly helpful! I have some questions I hope you are willing to answer. Thanks in advance!

Water: can I use snow scraped off the top of a snow bank? How about off the grass?

Sphagnum moss: should I use (dried is what I have) sphagnum moss to top-dress when I am starting seeds? Do I top-dress at all when starting seeds? I will also be purchasing peat moss.

Sand: so far the only silica sand I’ve found locally, although I haven’t exhausted my resources, is labeled #20/#40. Am I correct in assuming it is too fine because of the #40?

Watering: should the pots be in a tray of water? If so, on the bottom of the tray or on some type of media? How much water should be in the tray? I’m confused about how the plants have to stay wet but avoid root rot.

Lighting: my grow lights I currently have are 2-ft 24-watt LEDs that are supposed to be 15” away for germination and seedlings. Would I still follow that for germinating sundews? I currently use two per shelf of my mini-greenhouse.
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By Intheswamp
Posts:  3108
Joined:  Wed May 04, 2022 2:28 pm
We have little snow here in south Alabama but for some reason I'm under the impression that snow contains some micronutrients that rain does not contain...nutrients/fertilizer should be avoided. That includes any Miracle-Gro products.

Both sphagnum moss or peat should work okay. Some people prefer one over the other. The main thing is to have a finely chopped layer, not a coarse layer, for the seeds to fall on. If the surface is rough then the tiny seeds may fall down into the darkness of cracks and crevices and fail to get to the light once they sprout. A fine layer will keep them on the surface and in good contact with the moist media. About 50% of the time I use finely chopped sphagnum moss for the seedbed and the other 50% of the time I use fine peat.

Good sand is a unicorn. Since sand-blasting has given silica sand a bad name, it's availability in coarse grades is very limited. A lot of people have gone to using pool filter sand which is in the grade that you mentioned and it works okay for them. A sand replacement is pumice is a west coast item and cost is prohibitive down my way. Much less expensive on the west coast. Perlite is my most-used "drainage" material.

I keep all of my plants pretty well sitting in 1/2 to 1 inch of water...depending on pot height. I use nothing in my trays, I just sit the pots on the bottom of the tray. One thing to be careful about is the drainage holes in the pot. If your tray is smooth bottomed you need to be sure that you drill some holes on the sides of the pots, just above the bottom. Otherwise, with only drain holes in the bottom the pots and sitting on the flat surface, the drain holes may get blocked and prevent water from entering the pot...holes in the sides are insurance against this happening. Having said all that, there are people who do not keep pots in trays, but they are more attentive than I am, I guess. Flytraps don't like it as wet as sundews and sarrs like it, though.

Carnivorous plants can seldom get too much long as the heat from the lights don't burn them. I have a 12" square, 100-watt panel that I keep roughly 15" above some grown plants *and* some seedlings. I've also got some 22W, roughly 12" square panels that I keep 1-2 inches above some seedlings and a few inches (3-4 inches) more above some larger plants.. The seeds don't necessarily need strong light to germinate but as soon as the seedlings break through the seed hulls they need good, life-giving basically you want the strong light on them before the seeds pop. Imagine how it works in nature...they grow in full sun. I would probably want the 24W pretty close to the seeds/seedlings. Hopefully that makes sense.

One other thing. Drosera seeds are *tiny* seeds, some tinier than others (orchid seeds are almost invisible). When you get your seeds *be sure* to handle the small seed envelopes over a white sheet of paper and move slowly. I usually work over a piece of paper that I've folded and taped the edges up to for a something like 3/4" sides...basically a tray. To this I add a small piece of paper, maybe 3x3 inches square...I'll slightly bent up three sides of this piece of paper. When I open one of the small seed envelopes I make sure that I'm holding it over the paper tray. I then take the piece of paper (holding it over the tray) and gently and slowly tap the seed envelope to empty a few seeds onto the small sheet of paper. Having the pot sitting right beside the paper tray I'll slightly tip the paper down toward the grow mix and slowly move the small piece of paper over the surface of the grow mix. While moving the paper I slowly shake and tap the paper to cause the seeds to slowly fall off the edge of the paper...all the time keeping the paper moving. It is *very* easy to dump a bunch of seeds in one spot. As you tap the paper the black seeds will roll toward the edge. Once you do a few seeds you'll catch on to it. One thing to be aware of is not to sneeze or exhale strongly. This may seem trivial, but you may find yourself holding your breath as you sow the seeds and then suddenly "pheewww!!" ...out comes your breath. I've heard of this happening to *some* people. ;)

Some people bag/cover the seeds that are germinating to retain moisture. I've done it both ways...covered and uncovered. The main things is that the surface the seeds lay on remains good and moist...if uncovered make sure the water level in your tray/saucer/bowl is fairly deep so the surface is good and wet. If you cover/bag the pot then the moisture will be captive and you'll need very little water in the tray. With a covered setup, fungus is more apt to happen. With an uncovered setup you have to be sure you keep an adequate amount of water present. I'm still trying to figure out which way works best for me.

These are just my opinions, people do these things differently. :)

Good light, high humidity, warmth...that's what the seeds need.
Best wishes.
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By Panman
Posts:  6231
Joined:  Wed Mar 04, 2020 8:41 pm
Hedonista wrote:Water: can I use snow scraped off the top of a snow bank? How about off the grass?
As I understand it, snow actually picks up more pollutants on its way down than rain. If you use it, you will need to filter it through a coffee filter or something like that.
Hedonista wrote:Sphagnum moss: should I use (dried is what I have) sphagnum moss to top-dress when I am starting seeds? Do I top-dress at all when starting seeds? I will also be purchasing peat moss.
I find that chopping sphagnum very fine and top dressing before sowing the seeds helps to keep the seeds wet and make better contact with the substrate.
Hedonista wrote:Sand: so far the only silica sand I’ve found locally, although I haven’t exhausted my resources, is labeled #20/#40. Am I correct in assuming it is too fine because of the #40?
I'm not sure about the sand, but it is heavy. I personally use perlite more often and I'm starting to experiment with pumice.
Hedonista wrote:Watering: should the pots be in a tray of water? If so, on the bottom of the tray or on some type of media? How much water should be in the tray? I’m confused about how the plants have to stay wet but avoid root rot.
That's a good question but the answer is, "it depends". It depends on what you are growing, where you are growing it, and how big the pots are. Generally speaking, a shallow tray of water allowed to dry out between watering seems to be the best general rule.
Hedonista wrote:Lighting: my grow lights I currently have are 2-ft 24-watt LEDs that are supposed to be 15” away for germination and seedlings. Would I still follow that for germinating sundews? I currently use two per shelf of my mini-greenhouse.
Another, "it depends". LED lights vary wildly and wattage isn't a good gauge of use. Lumens is better but still not precise. Generally speaking, the lights will be fine for germinating but you will have to watch the plants to see if they are getting enough light. If they are growing pale and leggy, move them closer to the light. Also remember that the light is more intense directly under the light and less at the edges. I use this to my advantage by growing the light intensive plants in the center of the shelf and the less demanding ones toward the sides.
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